For Linus Pauling, it all started to go wrong when he changed his breakfast routine. In 1964, at the age of 65, he started adding vitamin C to his orange juice in the morning. It was like adding sugar to Coca Cola, and he believed – wholeheartedly, sometimes vehemently  – that it was a good thing.

Before this, his breakfasts were nothing to write about. Just that they happened early every morning before going to work at California Institute of Technology, even on weekends. He was indefatigable, and his work was fruitful.

At the age of 30, for instance, he proposed a third fundamental way that atoms are held together in molecules, melding ideas from both chemistry and quantum mechanics. Twenty years later, his work into how proteins (the building blocks of all life) are structured helped Francis Crick and James Watson decode the structure of DNA (the code of said building blocks) in 1953. 

The next year, Pauling was awarded a Nobel Prize in Chemistry for his insights into how molecules are held together. As Nick Lane, a biochemist from University College London, writes in his 2001 book Oxygen, “Pauling… was a colossus of 20th Century science, whose work laid the foundations of modern chemistry.”

Linus Pauling was one of our most influential scientists, yet his belief in the power of antioxidants may have set us down a dangerous path

But then came the vitamin C days. In his 1970 bestselling book, How To Live Longer and Feel Better, Pauling argued that such supplementation could cure the common cold. He consumed 18,000 milligrams (18 grams) of the stuff per day, 50 times the recommended daily allowance.

In the book’s second edition, he added flu to the list of easy fixes. When HIV spread in the US during the 1980s, he claimed that vitamin C could cure that, too.

In 1992, his ideas were featured on the cover of Time Magazine under the headline: “The Real Power of Vitamins”. They were touted as treatments for cardiovascular diseases, cataracts, and even cancer. “Even more provocative are glimmerings that vitamins can stave off the normal ravages of ageing,” the article claimed.

Sales in multivitamins and other dietary supplements boomed, as did Pauling’s fame.

But his academic reputation went the other way. Over the years, vitamin C, and many other dietary supplements, have found little backing from scientific study. In fact, with every spoonful of supplement he added to his orange juice, Pauling was more likely harming rather than helping his body. His ideas have not just proven to be wrong, but ultimately dangerous. 

Pauling was basing his theories on the fact that vitamin C is an antioxidant, a breed of molecules that includes vitamin E, beta-carotene, and folic acid. Their benefits are thought to arise from the fact that they neutralise highly reactive molecules called free-radicals.

In 1954, Rebeca Gerschman then at the University of Rochester, New York, first identified these molecules as a possible danger – ideas expanded upon by Denham Harman, from the Donner Laboratory of Medical Physics at UC Berkeley in 1956, who argued that free radicals can lead to cellular deterioration, disease and, ultimately, ageing.

Throughout the 20th Century, scientists steadily built on his ideas and they soon became widely accepted.

Here’s how it works. The process starts with mitochondria, those tiny combustion engines that sit within our cells. Inside their internal membranes food and oxygen are converted into water, carbon dioxide, and energy. This is respiration, a mechanism that fuels all complex life.

‘Leaky watermills’

But it isn’t so simple. In addition to food and oxygen, a continuous flow of negatively charged particles called electrons is also required. Like a subcellular stream downhill powering a series of watermills, this flow is maintained across  four proteins, each embedded in the internal membrane of the mitochondria, powering the production of the end product: energy.

This reaction fuels everything we do, but it is an imperfect process. There is some leakage of electrons from three of the cellular watermills, each able to react with oxygen molecules nearby. The result is a free radical, a radically reactive molecule with a free electron. 

Oxygen is the breath of life, but it also holds the potential to make us old, decrepit, and then dead

In order to regain stability, free radicals wreak havoc on the structures around them, ripping electrons from vital molecules such as DNA and proteins in order to balance its own charge. Although inconceivably small in scale, the production of free radicals, Harman and many others posited, would gradually take its toll on our entire bodies, causing mutations that can lead to ageing and age-related diseases such as cancer.

In short, oxygen is the breath of life, but it also holds the potential to make us old, decrepit, and then dead.

Clinical trials are the only ways to reveal the effects of a drug – and investigations into antioxidants have produced some shocking results (Credit: Alamy)

Shortly after free radicals were linked to ageing and disease, they were seen as enemies that should be purged from our bodies. In 1972, for example, Harman wrote, “Decreasing [free radicals] in an organism might be expected to result in a decreased rate of biological degradation with an accompanying increase in the years of useful, healthy life. It is hoped that [this theory] will lead to fruitful experiments directed toward increasing the healthy human lifespan.” 

He was talking about antioxidants, molecules that accept electrons from free radicals thereby diffusing the threat. And the experiments he hoped for were sown, nurtured, and replicated over the next few decades. But they bore little fruit.

The results were the largely the same: an excess of antioxidants didn’t quell the ravages of ageing, nor stop the onset of disease

In the 1970s and into the 80s, for example, many mice – our go-to laboratory animal – were prescribed a variety of supplementary antioxidants in their diet or via an injection straight into the bloodstream. Some were even genetically modified so that the genes coding for certain antioxidants were more active than non-modified lab mice. 

Although different in method, the results were the largely the same: an excess of antioxidants didn’t quell the ravages of ageing, nor stop the onset of disease.

“They never really proved that they were extending lifespan, or improving it,” says Antonio Enriquez from the Spanish National Centre for Cardiovascular Research in Madrid. “Mice don’t care for [supplements] very much.”

Far from protecting us from disease, one study found that vitamin supplements increased the incidence of lung cancer among smokers (Credit: Alamy)

What about humans? Unlike our smaller mammalian kin, scientists can’t take members of society into labs and monitor their health over their lifetime, while controlling for any extraneous factors that could bias the results at the end. But what they can do is set up long-term clinical trials.

The premise is pretty simple. First, find a group of people similar in age, location, and lifestyle. Second, split them into two subgroups. One half receives the supplement you’re interested in testing, while the other receives a blank – a sugar pill, a placebo. Third, and crucially to avoid unintentional bias, no one knows who was given which until after the trial; not even those administering the treatment. 

The incidence of lung cancer increased by 16% in the group given vitamin supplements

Known as a double-blind control trial, this is the gold standard of pharmaceutical research. Since the 1970s, there have been many trials like this trying to figure out what antioxidant supplementation does for our health and survival. The results are far from heartening.

In 1994, for example, one trial followed the lives of 29,133 Finish people in their 50s. All smoked, but only some were given beta-carotene supplements. Within this group, the incidence of lung cancer increased by 16%.

A similar result was found in postmenopausal women in the U.S. After 10 years of taking folic acid (a variety of B vitamin) every day their risk of breast cancer increased by 20%relative to those women who didn’t take the supplement. 

It gets worse. One study of more than 1,000 heavy smokers published in 1996 had to be terminated nearly two years early. After just four years of beta-carotene and vitamin A supplementation, there was a 28% increase in lung cancer rates and a 17% increase in those who died.

These aren’t trivial numbers. Compared to placebo, 20 more people were dying every year when taking these two supplements. Over the four years of the trial, that equates to 80 more deaths. As the authors wrote at the time, “The present findings provide ample grounds to discourage use of supplemental beta-carotene and the combination of beta-carotene and vitamin A.”

Fatal ideas

Of course, these notable studies don’t tell the full story. There are some studies that do show benefits of taking antioxidants, especially when the population sampled doesn’t have access to a healthy diet. 

But, according a review from 2012 that noted the conclusions of 27 clinical trials assessing the efficacy of a variety of antioxidants, the weight of evidence does not fall in its favour.

Just seven studies reported that supplementation led to some sort of health benefit from antioxidant supplements, including reduced risk of coronary heart disease and pancreatic cancer. Ten studies didn’t see any benefit at all – it was as if all patients were given the sugar pill also (but, of course, they weren’t). That left another 10 studies that found many patients to be in a measurably worse state after being administered antioxidants than before, including an increased incidence of diseases such as lung and breast cancer.

The idea that antioxidant supplements are a miracle cure is completely redundant – Antonio Enriquez

“The idea that antioxidant [supplementation] is a miracle cure is completely redundant,” says Enriquez. Linus Pauling was largely unaware of the fact that his own ideas could be fatal. In 1994, before the publication of many of the large-scale clinical trials, he died of prostate cancer. Vitamin C certainly wasn’t the cure-all that he cantankerously claimed it was up until his last breath. But did it contribute to a heightened risk? 

Dosing up on vitamin C does not even help us fight the common cold (Credit: Alamy)

We’ll never know for sure. But given that multiple studies have linked excess antioxidants to cancer, it certainly isn’t out of the question. A study published in 2007 from the US National Cancer Institute, for instance, found that men that took multivitamins were twice as likely to die from prostate cancer compared to those who didn’t. And in 2011, a similar study on 35,533 healthy men found that vitamin E and selenium supplementation increased prostate cancer by 17%.

Ever since Harman proposed his great theory of free radicals and ageing, the neat separation of antioxidants and free radicals (oxidants) has been deteriorating. It has aged.

Antioxidant is only a name, not a fixed definition of nature. Take vitamin C, Pauling’s preferred supplement. At the correct dose, vitamin C neutralises highly charged free radicals by accepting their free electron. It’s a molecular martyr, taking the hit upon itself to protect the cellular neighbourhood. 

But by accepting an electron, the vitamin C becomes a free radical itself, able to damage cell membranes, proteins and DNA. As the food chemist William Porter wrote in 1993, “[vitamin C] is truly a two-headed Janus, a Dr Jekyll-Mr Hyde, an oxymoron of antioxidants.”

Thankfully, in normal circumstances, the enzyme vitamin C reductase can return vitamin C’s antioxidant persona. But what if there’s so much vitamin C that it simply can’t keep up with supply? Although such simplifying of complex biochemistry is in itself problematic, the clinical trials above provide some possible outcomes.  

Divide and conquer

Antioxidants have a dark side. And, with increasing evidence that free radicals themselves are essential for our health, even their good side isn’t always helpful.

Without free radicals, cells would continue to grow and divide uncontrollably

We now know that free radicals are often used as molecular messengers that send signals from one region of the cell to another. In this role, they have been shown to modulate when a cell grows, when it divides in two, and when it dies. At every stage of a cell’s life, free radicals are vital.

Without them, cells would continue to grow and divide uncontrollably. There’s a word for this: cancer.

We would also be more prone to infections from outside. When under stress from an unwanted bacterium or virus, free radicals are naturally produced in higher numbers, acting as silent klaxons to our immune system. In response, those cells at the vanguard of our immune defense – macrophages and lymphocytes – start to divide and scout out the problem. If it is a bacterium, they will engulf it like Pac-Man eating a blue ghost.

It is trapped, but it is not yet dead. To change that, free radicals are once again called into action. Inside the immune cell, they are used for what they are infamous for: to damage and to kill. The intruder is torn apart.

From start to finish, a healthy immune response depends on free radicals being there for us, within us. As geneticists Joao Pedro Magalhaes and George Church wrote in 2006: “In the same way that fire is dangerous and nonetheless humans learned how to use it, it now appears that cells evolved mechanisms to control and use [free radicals].”

Put another way, freeing ourselves of free radicals with antioxidants is not a good idea. “You would leave the body helpless against some infections,” says Enriquez.

Few would dispute that a balanced diet is essential for good health, but most of us don’t need supplements to meet our nutritional needs (Credit: Getty Images)

Thankfully, your body has systems in place to keep a your inner biochemistry as stable as possible. For antioxidants, this generally involves filtering any excess out of the bloodstream into urine for disposal. “They go in the toilet,” says Cleva Villanueva from Instituto Politécnico Nacional, Mexico City, in an email.

“We’re very good at balancing things out so that the affect [of supplementation] is moderate whatever you do, which we should be grateful for,” says Lane. Our bodies have been selected to balance the risk of oxygen ever since the first microbes started to breathe this toxic gas. We can’t change billions of years of evolution with a simple pill.

No one would deny that vitamin C is vital to a healthy lifestyle, as are all antioxidants, but unless you are following doctor’s orders, these supplements are rarely going to be the answer for a longer life when a healthy diet is also an option. “Administration of antioxidants is justified only when it is evident that there is a real deficiency of a specific antioxidant,” says Villanueva. “The best option is to get antioxidants from food because it contains a mixture of antioxidants that work together.”

“Diets rich in fruits and vegetables have been shown generally to be good for you,” says Lane. “Not invariably, but generally that’s agreed to be the case.” Although often attributed to antioxidants, the benefits of such a diet, he says, might also hail from a healthy balance of pro-oxidants and other compounds whose roles aren’t yet fully understood.

After decades of unlocking the baroque biochemistry of free radicals and antioxidants, hundreds of thousands of volunteers, and millions of pounds spent on clinical trials, the best conclusion that 21st Century science has to offer is also found within a child’s classroom – eat your five-a-day.

By Alex Riley

8 December 2016

The sugar industry financed nutritional studies, released in 1967, that downplayed the sweetener’s relation to heart disease, placing the blame on saturated fats instead. Those highly influenced findings have stuck for five decades.

One of the scientists involved even helped develop the government-issued nutrition guidelines which contained cautions on the evils of red meat while scarcely mentioning the dangers of sugar, if at all.

These revelations make the release of a new book by food-industry expert Jeff Scot Philips, Big Fat Food Fraud: Confessions of a Health-Food Hustler (Regan Arts), well-timed. Philips was a personal trainer who founded a health-food manufacturing company that prepackaged healthy meals. He is now reformed from that industry, and spends his time educating people on how almost everything we hear about nutrition — including from medical experts — may be false. Much of it, he says, is specially designed not to improve our health, but to separate us from our money.

In the book, Philips outlines a slew of ways we have been — and are still being — conned by the food industry. Here are just a few.

The yolk’s on eggs

Eggs have had a bad name in the past.Source:istock

If you want to see how long inaccurate nutritional information can persevere, just take a look at eggs.

When Kellogg marketed its first food product, Cornflakes, in 1906, Philips writes that the company “mounted a vicious marketing campaign against the egg industry … claim[ing eggs] led to heart attacks.” The information was baseless fiction designed to sell cereal, but fear of eggs continues to this day.

“Are eggs healthy” and “Are eggs bad for you” are two of the top Google searches for this breakfast staple, despite the American Heart Association declaring eggs healthy in 2000, a finding reaffirmed by the government, in even stronger language, earlier this year.

Sometimes the food regulators are complicit

Philips shows that in some cases the food regulators may actively be making our food less healthful. A USDA (US Department of Agriculture) agent who worked with Philips’s company said he couldn’t approve calling a salmon dish “healthy” because the fat content was too high. The agent offered a solution: not to lower the fat content, but rather to add sugar or carbs to the meal.

“It’s the nutrition label,” the agent told him. “The guideline is about the ratio of fat grams to total grams in a serving.”

“That has nothing to do with health!” Philips said.

“Have you ever seen a Lean Cuisine meal without some bread or pasta in it?” the agent said, explaining, “The total grams of food go up while the fat grams stay the same; this evens out the ratio.”

The cover of Jeff Scot Philips’ new book.Source:Supplied

It’s a numbers game

Given the growing interest in eating healthfully, finding trans fat-free and sugar-free food is a top concern for many people. But the sad fact is that many foods marketed as trans fat-free or sugar-free might actually be loaded with them.

“Legally, as long as the trans fats-per-serving is equal to or less than 0.5 grams, we were allowed to list them as zero on the label,” Philips writes of his former company. But he also notes that brands are legally allowed to set the serving sizes on their packaging (1 serving, 3½ servings per bag, etc.) however they want.

So if a food contains too much trans fat or sugar to be considered healthy, a marketer can make it seem like far less by creating smaller portion sizes.

“If one of our meals contained 20 grams of sugar, we simply chopped the serving size down to four per container, and listed five grams of sugar on the nutrition label,” Philips writes.

Since health-food marketers need to be able to claim their foods are trans fat-free, they simply play with portion sizes until the math works.

“Nobody could stop us from marking a food that actually had 5 grams of trans fats at zero grams,” he writes, “simply by listing the servings-per-container at 10.”

Author Jeff Scot Philips.Source:Supplied

Doctors drink the Kool-Aid

Even the nutrition information you get from your physician might be false — because the doctor might be getting that information from marketers like Philips.

In the book, he mentions a computer program called Infusionsoft that handles all ends of the consumer-marketing process in order to target local health and nutrition pros with the newest findings — which are typically sponsored, created or manipulated by marketers — so that these experts can then promote these findings to their patients and clients.

Philips cites an example of a marketing campaign he used to sell more smoothies and protein bars. He knew of one doctor in particular who prided herself on knowing all the new info; one of her patients was also a Philips customer. Philips bombarded the doctor with messages about “new research” that found calorie counting was paramount to weight loss, and therefore, supplements like smoothies and protein bars could be more effective than “real” food if they had fewer calories.

He saw the success in his campaign via his customer, who, based on her doctor’s advice, started buying more of his smoothies and protein bars — and gained 23 pounds in the process.

Given all he knows about the industry, Philips’s own philosophy on food is to stick to the basics: eat more protein and less sugar, avoid processed food or anything that comes in a box, and, most of all, ignore marketing terms and nutrition labels, because they aren’t educating us the way we think they are.

“The cold truth is: Food labels aren’t there to educate you,” he writes. “They’re there to help market to you.”

This article originally appeared on The New York Post.

The gut microbiota is the community of bugs, including bacteria, that live in our intestine. It has been called the body’s “forgotten organ” because of the important role it plays beyond digestion and metabolism.

You might have read about the importance of a healthy gut microbiota for a healthy brain. Links have been made between the microbiota and depression, anxiety and stress. Your gut bacteria may even affect how well you sleep.

But it can be difficult to work out exactly how far the science has come in this emerging field of research. So what evidence is there that your gut microbiota affects your brain?

READ MORE:
* Dr Libby: Daily habits to help keep your gut healthy
* 10 foods to boost your digestion
* 6 ways to keep your metabolism revved as you get older
* Five metabolism myths, busted: Why eating carbs at night is fine

HOW DOES YOUR GUT TALK TO YOUR BRAIN?
When you’re healthy, bacteria are kept safely inside your gut. For the most part, the bacteria and your gut live in harmony. (The gut has been known to nurture or even control the behaviour of the bacteria for your well-being.)

So how do the bacteria get their signal out? 

The best evidence is that the normal channels of communication from your gut are being hijacked by the bacteria.

The gut has a bi-directional relationship with the central nervous system, referred to as the “gut-brain axis”. This allows the gut to send and receive signals to and from the brain.

A recent study found that the addition of a “good” strain of the bacteria lactobacillus (which is also found in yoghurt) to the gut of normal mice reduced their anxiety levels. The effect was blocked after cutting the vagus nerve – the main connection between brain and gut. This suggests the gut-brain axis is being used by bacteria to affect the brain.

This link was clarified in a study where bacterial metabolites (by-products) from fibre digestion were found to increase the levels of the gut hormone and neurotransmitter, serotonin. Serotonin can activate the vagus, suggesting one way your gut bacteria might be linked with your brain.

There are many other ways gut bacteria might affect your brain, including via bacterial toxins and metabolites, nutrient-scavenging, changing your taste-receptors and stirring up your immune system.

HOW CAN THE GUT AFFECT YOUR MENTAL HEALTH?
Two human studies looked at people with major depression and found that bacteria in their faeces differed from healthy volunteers. But it’s not yet clear why there is a difference, or even what counts as a “normal” gut microbiota.

In mouse studies, changes to the gut bacteria from antibiotics, probiotics (live bacteria) or specific breeding techniques are associated with anxious and depressive behaviours. These behaviours can be “transferred” from one mouse to another after a faecal microbiota transplant.

Even more intriguingly, in a study this year, gut microbiota samples from people with major depression were used to colonise bacteria-free rats. These rats went on to show behavioural changes related to depression.

Stress is also likely to be important in gut microbiota and mental health. We’ve known for a long time that stress contributes to the onset of mental illness. We are now discovering bi-directional links between stress and the microbiota.

In rat pups, exposure to a stressor (being separated from their mums) changes their gut microbiota, their stress response, and their behaviour. Probiotics containing “good” strains of bacteria can reduce their stress behaviours.

HOW GUT MICROBIOTA AFFECTS YOUR MOOD
Medical conditions associated with changes in mood, such as irritable bowel syndrome (IBS) and chronic fatigue syndrome (CFS), might also be related to gut microbiota.

IBS is considered a “gut-brain disorder”, since it is often worsened by stress. Half of IBS sufferers also have difficulties with depression or anxiety.

Ongoing research is investigating whether gut bacteria are one reason for the mood symptoms in IBS, as well as the gastrointestinal pain, diarrhoea and constipation.

Similarly, CFS is a multi-system illness, with many patients experiencing unbalanced gut microbiota. In these patients, alterations in the gut microbiota may contribute to the development of symptoms such as depression, neurocognitive impairments (affecting memory, thought and communication), pain and sleep disturbance.

In a recent study, higher levels of lactobacillus were associated with poorer mood in CFS participants. Some improvements in sleep and mood were observed when patients used antibiotic treatment to reduce gut microbial imbalance.

The exact contributions of stress and other factors such as intestinal permeability (which allows nutrients to pass through the gut) to these disorders are not understood. But the downstream effects seem to be involved in IBS, inflammatory bowel conditions, CFS, depression and chronic pain.

HOW OUR GUT AFFECTS OUR SLEEP
Our mental health is closely linked to the quality and timing of our sleep. Now evidence suggests that the gut microbiota can influence sleep quality and sleep-wake cycles (our circadian rhythm).

A study this year examined patients with CFS. The researchers found that higher levels of the “bad” clostridium bacteria were associated with an increased likelihood of sleep problems and fatigue, but this was specific to females only. This suggests that an unbalanced gut may precipitate or perpetuate sleep problems.

There is emerging evidence that circadian rhythms regulate the gut immune response. The effect of immune cells on the biological clock could provide insights into the possible bi-directional relationship between sleep and the gut. For example, data from animal studies suggests that circadian misalignment can lead to an unbalanced gut microbiota. But this effect can be moderated by diet.

There is growing concern that disruptions to our circadian timing of sleep leads to a range of health issues, such as obesity, metabolic and inflammatory disease, and mood disorders. This is particularly important for shiftworkers and others who experience changes to their sleep/wake patterns.

WHAT THIS MEANS FOR TREATMENT
In terms of using interventions directed at the gut to treat brain disorders – so called “psychobiotics” – there is a lot of promise but little clear evidence.

Probiotic (live bacteria) treatments in mice have been shown to reduce cortisol, an important stress hormone, and decrease anxious and depressive behaviours.

Probiotic (live bacteria) can be found in yoghurt.

But there are very few studies in humans. A recent systematic review of all the human studies showed the majority do not show any effect of probiotics on mood, stress or symptoms of mental illness.

On the plus side, large studies show us that people who eat a balanced diet with all the usual good stuff (fibre, fresh fruit and vegetables) have lower rates of mental illness as adults and adolescents.

Clearly, diet affects both the gut microbiota and mental health. Research is ongoing to see whether it is a healthy gut microbiota that underlies this relationship.

A healthy gut microbiota is linked to a healthy brain. However there are only a handful of human studies demonstrating real-world relevance of this link to mental health outcomes.

There is still a way to go before we can say exactly how best to harness the microbiota in order to improve brain function and mental health.

– The Conversation

Iron – we know we need it, but perhaps we don’t know exactly why, what exactly iron is, how to get the amount we need, or even what that amount is.

Dr Cathy Stephenson shares all the key facts.

1. Iron deficiency is the most common dietary deficiency in the world. It is thought that up to 20 per cent of New Zealand women, and 3 per cent of men, may be lacking in this essential nutrient.

2. The rate of iron deficiency in children is not clear, but is likely to be high. Studies have reported rates as high as 8-14 per cent in New Zealand babies aged 6-24 months. Teenage years (around 11-14) are a risky time as well, because of rapid growth, and the onset of menstruation. In this group, the highest prevalence is in Maori and Pacific Island girls.

READ MORE:
* Are you getting enough iron in your diet?
* How to tell if you’re magnesium deficient 
* Is your body crying out for nutrients?
3. Iron is incredibly important for our bodies and minds. It enables blood cells to carry oxygen to our muscles and brains. It keeps us mentally fit, strong and able to fight infections. A lack of iron will cause anaemia, tiredness, lethargy, pallor, increased susceptibility to infections such as coughs, colds or thrush, irritability or grumpiness, and poor concentration. In children especially, being iron deficient can contribute to difficulties in learning and retaining information.

4. Average daily requirements of iron vary throughout life depending on the stage you are in. For example, we know that babies and teenagers have much greater iron needs to cope with the rate of growth of their bodies. Women who are pregnant or breast-feeding need extra iron to cope with the baby’s demands; the same is true for women who are menstruating – they need extra iron to replace the iron lost each month with their period. Athletes may also need to be aware of their iron intake, as regular intense exercise will increase the body’s requirements.

5. In terms of recommended daily amounts, the guidelines are:

* Menstruating women – 18 milligrams per day (more if their periods are heavy)
* Pregnant women – 27mg per day
* Breast-feeding women – 10mg per day
* Other adults (male and female) – 8mg per day
* Children – depending on age, 7-10mg per day
* Babies – newborn babies have enough iron stores to last for the first 6 months of life; formula is fortified with iron, but breast milk isn’t so it is crucial that beyond 6 months of age, babies who are exclusively breast fed are also given iron-rich solids (such as fortified cereal).

6. Certain medical conditions can lead to iron deficiency, including Coeliac disease, kidney failure, heavy periods (known as menorrhagia), bleeding into the gut (example: from bowel cancer or ulcers) and chronic malabsorption. If you are a frequent blood donor, especially if you are female, you are at risk of becoming iron deficient – this is something the New Zealand Blood Service will screen you for.

7. Being vegetarian, especially if you are vegan, carries a higher risk of iron deficiency, if you have other risk factors such as heavy periods or pregnancy. Vegetarians need to eat about 80 per cent more iron in their diet than meat eaters do, as it is harder to absorb the iron found in vegetarian foods.

8. Iron in food comes in two forms – “haem” iron and “non-haem” iron. The body absorbs haem iron, much more readily than it can absorb non-haem iron. Foods containing high levels of haem iron include kidneys, liver, lamb, beef, canned sardines and tuna, chicken, pork and some fish. Foods containing non-haem iron include lentils, split peas, silverbeet, broccoli, spinach, kale, puha, eggs, wholemeal bread, raisins, dried apricots, porridge and other breakfast cereals with added iron, baked beans, tofu and nuts.

9. If you drink a lot of tea, coffee, coke or red wine with your food, it will inhibit the body’s ability to absorb iron. Adding something containing vitamin C will do the reverse – so either drinking real fruit juice or eating vitamin C-laden fruit (kiwi, blueberries, citrus fruit) with your meal is a great idea.

10. Iron deficiency can be diagnosed by a simple blood test which checks the level of iron stores (ferritin) in your body. If you are deficient, and there is no serious underlying cause, simple iron supplements available on prescription will correct the deficiency and make you function noticeably better!

DR CATHY STEPHENSON

It’s important to select the correct type of bread.

OPINION: I frequently get asked about bread. Elite athletes and the general public alike all seem to want to know if it is OK to eat.

I can understand the confusion; bread has become something of an enemy which may be attributed to low carbohydrate trends as well as its gluten content.

Bread comes in many forms, but for the most part contains flour, yeast, salt and water. Not all breads are equal and some varieties contain far more nutrients than others. Two slices of white bread (although very yummy) contain only 1.5g of fibre, whereas multigrain breads contain 5.2g fibre (depending on brand), more protein, and healthy fats and vitamins due to the seeds and grains. The higher fibre content makes these breads more filling too, meaning you eat fewer slices to feel satisfied.

Supplied

Performance nutritionist Lillian Morton.

I think this is where the confusion arises.

If one uses bread as a food rather than a filler you eat smaller amounts. Many people use bread as a quick and easy alternative to making something else.

I’ll use an example to explain what I mean. I see time and time again in food diaries how bread used as a quick fix. You are feeling hungry, you scan the pantry and decide toast is easiest, with perhaps peanut butter or jam. Two slices are not filling enough so you make an extra slice.

Yes, toast is a quick and easy option but if one lives on toast as a snack then you miss out on other key nutrients that you may have eaten if you had perhaps made a smoothie (milk, yoghurt, banana, and berries), or had a pottle of yoghurt and a piece of fruit.

Another example is the humble sandwich. I frequently see sandwiches in food diaries that contain bread, ham, chicken or luncheon with some lettuce and mayo. Not very filling and so three to four sandwiches are eaten.

A better way to use bread is as a small part of the meal rather the primary ingredient. A good sandwich is made from multigrain bread, filled with salad ingredients such as lettuce, tomato, grated carrot, avocado, beetroot, sliced red onion, cucumber, and ham, chicken or some other protein source. This kind of sandwich is far more filling – and it’s yummy too.

There are some people unable to eat standard breads due to conditions such as coeliac disease and gluten intolerance. However, there are many bread alternatives available, and the same rules apply.

So, yes, you can eat bread, just don’t live on it.

Take a moment and think about how you use bread. If you are using bread as a substitute for other foods because you are too busy, too lazy, or too tired to prepare something else, then take some time to think about how you can change this.

Eat plenty of fresh vegetables and fruit, eat healthy snacks and avoid toast for dinner.

Lillian Morton is a performance nutritionist and senior academic staff member. She holds an MSc in sport and exercise science and is currently working towards her PhD.

Is there any other substance that offers a remedy for as many of our health foibles as omega-3?

Sourced from two polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and to a lesser extent alpha-linolenic acids (ALA), these essential fatty acids are considered vital to maintaining optimum brain function, heart health and even said to help inflammation and aid in easing the pain of arthritis.

In fact, to hear Dr William Harris speak about them, omega-3s are the holy grail of health and overall wellbeing:

“There are two main essential fats: omega-6 and omega-3 and both have their uses – but omega 3 is the big one,” he says.

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“The primary source for these is oily fish, but they can come in plant form – things like flaxseed and soybean – but these produce a different kind of omega-3 source, ALA, which isn’t as easily converted into omega-3 as EPA and DHA.”

A professor at the Sanford School of Medicine at the University of South Dakota, Harris has spent the past 30 years studying and testing the seemingly endless benefits that come from these essential fatty acids.

“Unlike a lot of other vitamins and mineral fads – like vitamin E and beta carotene – omega-3 has stayed the course and each new study shows the benefits it has on our health,” he says.

“Each study clarifies what it does. It’s been shown to help brain health, depression, dementia and there is something there that omega-3 helps with. It just needs to be worked out. We’re just about to start this.”

THE NEW CHOLESTEROL

Currently in Australia to launch a national omega-3 level-testing scheme called the omega-3 Index, Harris doesn’t pull any punches when it comes to expressing just how important these substances are as an indicator to our health.

“I view omega-3 as the new cholesterol,” he says.

“It’s a risk indicator for heart disease that you can actually do something about without the need for drugs. In fact, I would bet that omega-3 levels are the most important indicator of risk factors for heart disease.”

Once rolled out, the omega-3 Index will be as simple as pricking finger with a pin. According to Harris, all one needs to do is request the test from a doctor or naturopath. The sample will be forwarded on to a lab where the level of omega-3s in the blood will be tested and recorded as a percentage (“Health target levels are between eight and 12 and low is considered below four,” says Harris).

According to Harris, this will help doctors and health professionals keep track of a patient’s heart health to prevent the possibility of heart attacks.

But for all the this amazing goodness that omega-3s offer, there’s just one catch – our body doesn’t produce them naturally.

A FISHY STORY INDEED

You see, like some sort of biological joke, it seems that for all omega-3s’ benefits to the body, we can only ever get them from external sources. And the primary source of this, is fish.

Fatty, or oily, fish such as salmon with the skin on, sardines, mackerel and herring are the best sources of omega-3.

“Fish is our primary source of EPA and DHA,” says Harris.

“These have higher potency, are much more easily converted into omega-3 and there is more evidence that shows EPA and DHA are better for heart health and brain function overall.”

Obviously something that the average vegan or vegetarian might have something of an issue with. And while fish oil supplements may seem like an easy solution to making sure your brain and heart are being fed the nutrients they need, consumer advocate Choice has already pointed out that the potency of many of these isn’t high enough to offer any benefits.

So what alternatives do our non-animal eating fellows have?

Dietitian and nutritionist Lauren Blair says that, while not offering as intense a hit as their marine alternatives, there are several plant-based sources of omega-3 that vegans and vegetarians can tap into.

“Plant-based sources of omega 3 are only marginally as effective as marine-based sources of omega-3,” she explains to Fairfax.

“So vegetarians and vegans need to take a few extra steps in order to maximise their omega-3 intake. I recommend eating good sources of whole-food, plant-based omega-3 (ALAs) including walnuts, chia seeds, linseeds, hemp seeds, soy beans, seaweeds and tofu while reducing the omega-6 foods in your diet as omega-6 can prevent omega-3 from being used properly in the body.”

According to Blair, you can do this by replacing sunflower, safflower and corn oils with mustard, walnut or chia seed oil.

And while it probably won’t appeal to those who embrace an ardent natural food philosophy, Harris says that there are several exciting developments in the GM industry that could help people who either can’t or won’t eat fish get the daily dose of omega-3.

“There are some GM oils made by Monsanto, one called Soy Mega, which is a derivative of the soybean and contains SDA, a compound one step closer to EPA than ALA. But, the crux is that it’s GM food which most vegans are not inclined to eat and also made by Monsanto, which doesn’t have the best of reputations.

“There is also the possibility of a supplement for vegans that uses an algae called OVEGA 3  and this has half a gram of EPA and DHA in each capsule.”

BENJAMEN JUDD

Clean eating is associated with the healthy lifestyle and body beautiful that is promoted by many online bloggers. While the term is heavily used in social media, there has never been any agreement on what it really means or any comprehensive studies examining the potential benefits of a clean eating lifestyle as a whole.

However, the core principles that the big names in this movement champion appear to be: eliminate processed food; reduce salt intake; eat more vegetables; choose whole grains; eliminate refined sugar; reduce alcohol. For some, you also need to be gluten, dairy, and soya free and to eat raw (depending on how militant you are, food has to be entirely uncooked or only mildly heated). And if you want to be completely “clean” you should probably be vegan, too. Quite a list, then.

And there are also some big players online – including Food Babe, who was voted by Time as one of the 30 most influential people on the internet – who have significantly influenced this trend.

While some of the principles of clean eating are in line with the best available evidence for losing weight or preventing ill health – such as eating plenty of fruit and vegetables, sticking to wholegrains and limiting processed food – there are plenty of others that don’t stand up to scrutiny. It has been repeatedly proven that dietary restrictions such as a dairy-free diet or gluten-free diet are nutritionally substandard and studies have linked the introduction of a gluten-free diet with increased levels of psychological distress in coeliacs including depression and anxiety.

Some people find it difficult to understand why dietitians and doctors are against the clean eating phenomenon when there are still people eating burgers for breakfast and obesity is on the rise. However, some clean eating is sensationalist promotion of non-evidence based, and extremely restrictive, lifestyles that demonise everyday food essentials. And that can lead followers into having a sense of shame and failure for not eliminating “unclean” foods 100 per cent of the time – so you can see where the negativity from healthcare professionals stems from.

READ MORE:
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* Orthorexia nervosa: Do you have an unhealthy obsession with health?
* When clean eating spirals out of control
* Instagram’s ‘eat clean’ lifestyle may be doing more harm than good

There is significant research disproving many of the principles of the diet. Below are some of the big claims and why they don’t stack up.

CLEAN EATING CAN CURE DISEASE

Some clean eating bloggers claim to have cured themselves of diseases. The kinds of medical conditions that clean eating is supposed to cure are often conditions that are not well understood, such as chronic fatigue, which leaves sufferers desperate for a solution. And where there is desperation there is always someone willing to sell help – however unscientific.

One of the big names in clean eating who believes her diet controls her postural tachycardia syndrome (PoTs) – where standing up causes a drop in blood supply to the heart and brain and the heart races to compensate – intestinal issues and headaches through her method of a dairy free, gluten free vegan diet is Deliciously Ella. PoTS, however, has no proven link with food except that a higher salt intake is recommended to help keep blood pressure up. Having too little salt in the diet can exacerbate the problem. The reason that Ella is so much better now is much more likely to be age-related as we know that for 80 per cent of sufferers, symptoms disappear between the ages of 19-24. Ella was diagnosed aged 19 in 2011 and has been blogging about diet for four years.

One thing diet may have helped with though is Ella’s gastroinestinal issues. Her method of eating has a diet that is very low in fermentable carbohydrates or FODMAPs which have been robustly proven to be a cause of Irritable Bowel Syndrome (IBS) which affects up to one in five people.

CLEAN EATING MAKES YOU HAPPY!

Many of the clean eating bloggers promote themselves as a model of how you could look if you follow their lifestyle. But it is important to remember that it is their job to look the way they do. If you have a full-time job and a busy life, the chances of you cooking every meal from scratch, never having to grab a sandwich from the supermarket for lunch and being able to work out for two hours a day are very slim. If you try to model your life on theirs you are more than likely to end up feeling like a failure because it is simply not realistic.

Interestingly, many clean eating bloggers claim to have been depressed before clean eating. There has been lots of research into dietary treatments for depression by increasing an amino acid called tryptophan which is a precursor for serotonin production in the brain, which in turn influences good mood. To date, no trial has conclusively proven that increasing dietary tryptophan improves serotonin production or depressive symptoms but a diet in line with clean eating actually has the potential to be low in essential amino acids such as tryptophan.

What is more likely is that all the attention and apparent public approval received for losing weight and improving their appearance has temporarily improved their self-worth.

Clean Eating Is A Good Way To Lose Weight

Clean Eating Alice, 23, is another big name in the game. Alice isn’t vegetarian but her diet is very low in carbohydrate. She claims that her diet and exercise regime has immeasurably improved her health and happiness. It was reported that through her version of clean eating and intensive exercise, she dropped 16kg and reduced her body fat percentage from 30 per cent to just 15 per cent. 

Alice’s reported body fat percentage is concerning. The minimum essential fat for a woman is between 10-13 per cent – we need this amount to maintain our immune system and maintain healthy hormone levels. Many professional athletes will have a body fat percentage of up to 20 per cent with the normal healthy level around 25 per cent. So holding herself up as a realistic and achievable role model is highly misleading.

CLEAN EATING IS GOOD FOR GUT HEALTH

The Helmsley Sisters were some of the first to bring the clean eating trend to our attention. Their philosophy aims to help people with their digestion and relationship with food, and teach the importance of gut health. Their recipes eliminate gluten, grains and refined sugar (and minimise natural sugars). However, the majority of people tolerate gluten very well – the exceptions are for people with conditions such as coeliac disease – sugar is absorbed so efficiently it has no impact on digestion and grains provide high levels of prebiotics to feed the good bacteria in your gut. The best thing for gut health is a good, balanced diet.

CLEAN EATING PREVENTS AGEING

Many bloggers state that clean eating will keep you looking youthful. There is some compelling evidence that antioxidants found in fruit and vegetables can prevent premature skin ageing.

You do, however, also need plenty of good quality protein to maintain the integrity of your skin and therefore extreme clean eating could easily undermine the benefits of the antioxidants.

CLEAN EATING WILL DETOX YOUR BODY

Detox diets are all the rage and the clean eating crew all have their own version of a detox diet. Fortunately, no one needs a detox diet because our liver and our kidneys are always already doing this. Everyone would agree that excessive consumption of highly processed food with lots of additives is not a healthy way to eat. However, neither is following a highly restrictive diet for any amount of time and there is certainly no health benefits associated with “detoxing”.

Some clean eaters promote an alkaline diet to prevent excess acidity in the body. Ironically, our stomach acid is only slightly less acidic than battery acid so anything you eat will be immediately placed into a highly acidic environment where the pH is tightly controlled. You cannot manipulate your body’s pH through diet (as the below tweet suggests) and you don’t need to try.

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CLEAN EATING MAKES YOU HEALTHIER

There are even more extreme examples of clean eating out there including Freelee The Banana Girl who promotes a raw vegan diet of 15 bananas, 40 pieces of fruit and a couple of kilograms of potatoes a day. She claims that eating this way has cured her weight issues, depression, irritable bowel syndrome, chronic fatigue, poor digestion and acne.

It is hard to pin down the most concerning thing about this diet but the fact that Freelee is consuming 6.5 times more potassium than is recommended and encourages others to do so is a big one. She even consumes 30 per cent more potassium than is shown to cause excess potassium in the blood, which can lead to deadly changes in heart rhythm. That said, whether or not she is absorbing any of the nutrients in her food due to the amount of fibre she is taking in is questionable and if her bowel habits are normal and healthy it is a medical miracle.

Anyone can call themselves a nutritionist and there are many quick courses that give a false air of credibility. There are also no regulations around what people can and can’t recommend as being healthy. It should be very hard to maintain a voice of authority in an area in which you are totally unqualified and in a world where your self worth depends on “likes” and “views” and “followers”.

An obsession with clean eating and the shame that is often associated with eating foods considered to be dirty can also lead to mental health issues such as orthorexia, an eating disorder associated with obsessive healthy eating. Emmy Gilmore, clinical director of eating disorders clinic Recover, even suggested in a recent BBC documentary that many UK clean eating bloggers had sought help from her clinic. So rather than watch videos of supposedly physically healthy girls as gospel, it’s better to develop healthy eating habits that come from sound scientific advice and which balance all the nutrients your body needs.

And if you’re seeking professional advice, find a nutritionist with a degree or a registered dietitian – it’s a protected title so you can be certain that the advice you’re given will be scientifically robust.

– The Conversation

iSTOCK

Eating an English breakfast will certainly keep you hunger-free until lunchtime.

How good is sitting down to a plate of organic eggs, smashed avo and grilled mushrooms paired with a decent mug of petrol coffee first thing in the morning? Sounds delish.

But is eating breakfast integral to a healthy diet or have we simply become habitualised feeders?

For many adults, the message that breakfast is the most important meal of the day has been drummed into us from an early age. Television commercials, government-funded food guidelines and dietitians are determined to have us believe that a good, healthy diet starts with a morning meal.

But a growing number of experts, and a growing body of research, question the validity of these claims if not reject them all together.

READ MORE:
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Emma Boyd

Apple porridge is the perfect cereal fruit combo.

SO WHAT IS THE TRUTH?

Earlier this year, professor of pediatrics at Indiana University School of Medicine Aaron E. Carroll wrote an article for the New York Times questioning the push for breakfast in the media.

He pointed out that much of the data released in favour of eating breakfast was funded by groups, like Kellogg, who had a vested interest.

In fact, the phrase that breakfast is ‘the most important meal of the day’ was a 1944 marketing campaign launched by American company General Foods to encourage people to, you guessed it, buy more cereal.

But probably the most fascinating and poignant argument Carroll makes is how this research was – and still is – targeted towards children.

123RF

A fruit smoothie.

A good breakfast is regularly touted as being an essential part of their daily routine, particularly because it helps them perform better in school. But as Carroll points out, this research failed to take into account the general nutritional intake of the children being studied.

As Carroll noted, hunger “affects almost one in seven households in America, or about 15 million children”. So it makes sense then that kids who were going hungry at home would respond better when fed in the morning.

Carroll was also critical of studies that suggested kids who skip breakfast were more likely to be overweight than children who eat two breakfasts for the same reason – if you’re being nourished at home, you’re probably not starving at school.

SCIENCE VS PROFITS

Writing for Good Health (“the oldest health magazine in the world”) in 1917, Lenna F. Cooper stated that “in many ways, the breakfast is the most important meal of the day, because it is the meal that gets the day started.”

Not so coincidentally, Good Health also happened to be edited by Dr John Harvey Kellogg, the father of modern day flaked cereals. To say that Kellogg had an agenda when this was put into his magazine is an understatement.

But it’s also part of a bigger picture surrounding the science of breakfast and how research can be skewed to benefit the aims of the author.

Muesli and strawberry porridge.

In 2013, a paper published by The American Journal of Clinical Nutrition studied the literature surrounding links between breakfast and obesity. What they found was that scientists showed regular bias in their interpretation of research, favouring the notion there was a link between skipping breakfast and obesity even when no such evidence was apparent.

And only in a 2014 study conducted by Monash University, researchers found that skipping breakfast as part of intermittent fasting not only helped weight loss but also helped blood pressure and various forms of liver damage.

But this isn’t to say breakfast is bad and you shouldn’t be eating it. In fact, if you wake up hungry like those 15 million US school children then you most definitely should be eating it.

But eating it just out of habit? You can probably swap it out for an extra 30 minutes sleep.

– Juicedaily.com.au

Investing in your eye health is potentially one of the most important investments you can make.

From having regular eye checks and monitoring any degeneration through to supporting your eye health with a diet full of fresh whole foods – there are many different ways you can support these amazing organs.

The eyes connect to the body in various ways. Certain vitamins and minerals can protect against and, in some cases, even help prevent numerous diseases such as cataracts, glaucoma, and age-related macular degeneration.

READ MORE:
* Dr Libby: The psychology of eating – when food becomes your comfort
* Dr Libby: Try forming these small habits to boost your health
* Dr Libby: Daily habits to help keep your gut healthy
* Dr Libby: 10 foods that help sugar cravings

Piccianeri | Dreamstime

Citrus fruits are a great source of vitamin C, which is critical to eye health.

VITAMIN A

Vitamin A has many functions, not only can it help maintain a strong immune system, but it’s also absolutely critical for keeping the retina healthy.

In fact in many third-world countries vitamin A deficiency is the leading cause of night-blindness, where you’re unable to see at night or in dim light. Night blindness is caused by a disorder of the cells in the retina that are responsible for vision in dim light.

Vitamin A is sometimes used to treat hereditary retina deformities and according to some studies supplementing with vitamin A may help slow the progression of the disease.

However, we also get vitamin A itself through the diet plus our bodies can convert plant chemicals (carotenoids) such as beta-carotene and alpha-carotene into vitamin A.

Coloured vegetables and fruit contain many carotenoids. A recent study conducted over a 10-year period found that consumption of fruits and vegetables, but in particular orange or yellow fruits and vegetables are the most protective against cardiovascular disease.

The same study named carrots as one of the most heart healthy vegetables because of its deep orange colour and therefore concentration of protective antioxidants and nutrients.

BETA-CAROTENE

Carotenoids are antioxidants that are plant pigments. This category of nutrients is considered by many eye-care experts to be the most protective for eye health.

One of the best recognised of the carotenoid family is beta-carotene. Beta-carotene has antioxidant effects and aids in maintaining good vision, as well as night vision. It is because of this function that we often hear the phrase eat your carrots, as they help you see at night.

Research indicates it may play a role in cataract prevention. Luckily, beta-carotene, which is converted into vitamin A in the body, is easily obtained through the diet. However, the conversion of these plant forms to retinol, a better-absorbed form of vitamin A, is not as well absorbed as it is from animal sources.

So there is no need to be concerned about eating too many foods that are a rich source of beta-carotene, as the body regulates how much is converted. In fact, they’re a wonderful inclusion in your diet for a number of health benefits. These foods include carrots, kumara, kale, spinach, papaya, capsicums, and pumpkin to name a few.

KEEP AN EYE ON THESE FOODS

1. Kale. Leafy green vegetables, like kale, are superstars for eye health! Particularly as they’re a good source of lutein and zeaxanthin, two antioxidants known to support healthy eye function. Evidence suggests that people with diets high in lutein were up to 23 per cent less likely to develop cataracts than those whose diets were low in this nutrient. If kale isn’t your thing, choose other dark leafy green vegetables, like spinach and silverbeet as they’re also good sources of lutein and zeaxanthin, as are egg yolks.

2. Salmon. There is evidence to suggest that diets rich in omega-3 fatty acids from fresh, cold-water fish like salmon and sardines, reduce the risk of developing eye disease later in life. If you’re a vegetarian or vegan include plant sources of omega-3 fatty acids such as flaxseeds or chia seeds.

3. Citrus fruit. Citrus fruits are a wonderful source of vitamin C, an antioxidant that is critical to eye health. Oranges, lemons, grapefruit and tangerine are all delicious and beneficial additions to the diet.

Dr Libby

Tired of the old argument pitting carbohydrates against fats? Seems you’re not alone.

Don’t knock all carbs and fats – that’s the message from a new report from The Lancet.

Nutrition experts are saying that debate is not what’s important – rather we should focus on the quality of the food in our diets.

A report just released by the prestigious medical UK journal The Lancet, which includes information from leading nutrition and public health researchers in New Zealand, says there’s a clear recommendation that we should be cutting our intakes of poor-quality foods containing lots of free sugars and saturated fats.

Instead of focusing on low fat versus low carb we should be eating a wider range of healthy fats and carbohydrates, says Professor Mann from the University of Otago’s Edgar Diabetes and Obesity Research Centre (EDOR).

“There are good fats, just as there are good carbohydrates that are associated with a reduced risk of heart disease, diabetes and colon cancer,” he says.

“Pitting one nutrient against another – such as fat versus carbs – risks confusing the public, health professionals and policy makers, and undermines confidence in evidence-based nutrition advice.”

The commentary, which also includes research from the University of Auckland and the Healthier Lives National Science Challenge, is based on the “totality of international evidence from objective, systematic and thorough expert reviews” of a range of different types of studies that evaluate the effects of foods and nutrients on health outcomes.

Prof Mann says the recommendations can be met easily by culturally diverse dietary patterns – from the traditional high-carbohydrate, low-fat diet of Japan, which is associated with longevity, to relatively high-fat, high-carbohydrate Mediterranean diets, which are associated with low risk of non-communicable diseases.

“What dietary patterns associated with the lowest risk of non-communicable diseases all have in common is that they tend to include lots of fibre-rich fruit and vegetables, legumes, pulses, nuts, wholegrains, and plant oils.”