Food as Medicine

Walk into any health shop and you'll find shelves of pills promising the goodness of a carrot, a blueberry or a bowl of greens. It's an appealing idea: all the benefits, none of the chopping. But when scientists have put that idea to the test, the results have been surprising, and sometimes sobering.

When the pills were put to the test

In the 1980s, researchers noticed that people who ate plenty of fruit and vegetables rich in beta-carotene, the orange pigment in carrots and sweet potatoes, had lower rates of lung cancer. It seemed logical that giving people beta-carotene as a supplement would protect them too.

Two large trials set out to prove it. One followed 29,000 men in Finland; another followed 18,000 people in the United States. Both had to report the opposite of what was expected. Among smokers, those taking beta-carotene supplements were more likely to develop lung cancer, not less.^1,2

A similar story unfolded with vitamin E. A major trial of 35,000 men, hoping to prevent prostate cancer, found that those taking vitamin E supplements had a slightly higher risk of it.³

The nutrients were the same ones found in food. What was different was everything else.

A carrot is not a delivery system for beta-carotene. It is a living package of hundreds of compounds, designed by nature to work together.

The orchestra inside an apple

100 g of fresh apple, about half a large apple, contains only around 6 mg of vitamin C. Yet when scientists at Cornell University measured its antioxidant power, it matched roughly 1,500 mg of vitamin C.⁴ The vitamin C itself played only a small part. The rest came from a whole family of plant compounds, polyphenols and flavonoids, working together. (See Stressed Plants, Stronger Medicine.)

Researchers now believe that the benefits of fruit and vegetables come from these compounds acting in combination, each one supporting and strengthening the others.⁵ More than 8,000 polyphenols have been identified so far. No supplement could ever contain them all, in the right balance, alongside the fibre, water and structure of the food itself.

Scientists call this structure the food matrix. It shapes how quickly nutrients are released, how much reaches your bloodstream and what your gut bacteria get to feed on. It's why whole fruit and fruit juice behave so differently in the body: in a study of nearly 190,000 adults, eating more whole fruit, especially blueberries, grapes and apples, was linked with a lower risk of type 2 diabetes, while drinking more fruit juice was linked with a higher one.⁶ (See Balancing the Sugar Seesaw.)

What whole foods give you that pills can't

• Fibre. In a major review for the World Health Organization, people eating 25–29 g of fibre a day had lower rates of heart disease, stroke, type 2 diabetes and bowel cancer than those eating less.⁷ In the UK, most adults eat around 20 g, well short of the 30 g that is recommended.⁸
• Food for your gut. Fibre and polyphenols feed the trillions of bacteria in your gut, which in turn make compounds that calm inflammation and support your immune system. (See The Master Regulator.)
• Natural balance. Food gives nutrients in the amounts and partnerships your body is used to, rather than in large isolated doses.
• Built-in helpers. Many nutrients are absorbed better with their natural partners, such as the healthy fats that help carry carotenoids from vegetables into the body.

The evidence for eating more plants is strong. A review of 95 studies found that the more fruit and vegetables people ate, up to about 800 g a day (around ten portions), the lower their risk of heart disease, stroke and early death.⁹

Investing in quality

If food is medicine, then quality matters. We think nothing of paying for the best supplements, yet we often choose the cheapest food. Turning that around is one of the most powerful changes you can make.

• Whole, not processed. The closer a food is to the way it grew, the more of its natural goodness it keeps. Processing strips away fibre, polyphenols and minerals, and often adds sugar, salt and additives.
• Organic where you can. A review of 343 studies found that organic crops contained more antioxidants than non-organic ones, between about 20% and 70% more depending on the compound, along with less of the toxic metal cadmium. Pesticide residues were found around four times less often.¹⁰ (See Why Eat Organic?)
• Fresh and in season. Produce eaten soon after harvest, at its natural time of year, tends to have more flavour and better keeps its nutrients.
• Local where you can. Buying from local farms, markets and veg box schemes supports growers near you, cuts packaging and transport, and lowers your carbon footprint, especially when it replaces air-freighted produce. Local food is often picked closer to ripeness, too.

If buying everything organic isn't possible, start with the foods you eat most often, and with those whose skins you eat, such as berries, apples, leafy greens and potatoes.

Nature's superfoods

"Superfood" isn't a scientific term, but some foods really do pack an exceptional amount of goodness into every mouthful. Building your meals around them is like stocking your own natural pharmacy:

• Berries: blueberries, blackberries and blackcurrants, rich in deep-coloured anthocyanins.
• Dark leafy greens: kale, spinach, chard and watercress, full of folate, magnesium and vitamin K.
• Cruciferous vegetables: broccoli, cabbage and Brussels sprouts, which contain sulforaphane-forming compounds.
• Beans and lentils: fibre, protein, iron and folate in one humble package.
• Nuts and seeds: walnuts, flaxseed, pumpkin and chia seeds, for healthy fats, zinc and magnesium.
• Oily fish: salmon, mackerel, sardines and herring, the richest food source of omega-3 fats.
• Fermented foods: live yoghurt, kefir, sauerkraut and kimchi, to feed and support your gut.
• Herbs and spices: turmeric, ginger, garlic, cinnamon and rosemary, some of the most concentrated sources of plant compounds in any kitchen.

When your plate is full of whole, high-quality food, your medicine cabinet can often become much emptier.

What your food is actually doing

Every nutrient on your plate has a job. Here are some of the most important, and where to find them:

• Omega-3 fats (oily fish, walnuts, flaxseed, chia). DHA, the main omega-3 in the brain and eyes, forms part of the membranes of nerve cells, helping messages pass smoothly between them. The body also uses omega-3s to make resolvins, molecules that actively bring inflammation to a close.¹¹
• Magnesium (leafy greens, pumpkin seeds, beans, cacao). Involved in more than 600 reactions in the body, magnesium is needed to make energy, relax muscles and calm the nervous system, partly by quietening over-excited nerve signals.¹² (See The Cortisol Clock.)
• B vitamins (whole grains, beans, lentils, eggs, leafy greens). These turn food into energy and help make the brain's chemical messengers, such as serotonin and dopamine. Folate and B12 are also needed to make healthy red blood cells and to keep genes working as they should.¹³ (See Not Written in Stone.)
• Vitamin C (peppers, citrus, berries, kale). Essential for making collagen, the protein that holds together skin, gums, blood vessels and joints, and for the immune cells that fight infection. It also helps the body absorb iron from plant foods.¹⁴
• Zinc (pumpkin seeds, lentils, oysters, eggs). Needed by the immune system, for wound healing, for taste and smell, and for healthy hormones and fertility.¹⁵ (See Fertile Ground.)
• Iron (lentils, beans, dark greens, red meat). Carries oxygen around the body in red blood cells. Low iron is one of the commonest causes of tiredness, especially in women.
• Vitamin K (leafy greens, fermented foods). Helps blood to clot and directs calcium into the bones rather than the arteries. (See Living Bones.)
• Polyphenols (berries, cacao, green tea, olive oil, herbs). Rather than simply mopping up damage, many of these plant compounds switch on the body's own protective and repair systems, and they feed the friendly bacteria in the gut.¹⁶
• Sulforaphane (broccoli, especially broccoli sprouts, and other cabbage-family vegetables). Activates the liver's own detoxification enzymes, helping the body clear harmful substances.¹⁷ (See Lightening the Load.)
• Chlorophyll (dark leafy greens, parsley, herbs). The green pigment that lets plants capture sunlight has a structure strikingly similar to haem in our own blood, with magnesium at its centre instead of iron. In the 1940s, water-soluble forms of chlorophyll were studied for healing wounds and were applied to injuries, including during the Second World War, and chlorophyllin is still used in some wound-care ointments today.¹⁸ Eaten, it has been shown to bind certain toxins in the gut: in one trial in an area at high risk of liver cancer, chlorophyllin taken with meals halved a marker of damage from aflatoxin, a toxin made by moulds.¹⁹

None of these work alone. A handful of spinach brings magnesium, folate, vitamin K, iron, chlorophyll and dozens of polyphenols together, in the balance the body evolved to use.

Fewer pills, better plates

With a diet like this, many of the supplements people take every day may simply not be needed. That said, supplements are tools, and in the right hands they can be very helpful. There are times when food alone may not be enough:

• Vitamin D in autumn and winter, when UK sunlight is too weak for the skin to make it. The NHS advises 10 micrograms a day.²⁰
• Folic acid before and during early pregnancy.
• Vitamin B12 for anyone following a vegan diet.
• A proven deficiency, such as low iron confirmed by a blood test.

The key word is proven. Taking a handful of supplements "just in case" can mean spending money on things you don't need, and occasionally taking doses that do more harm than good. Some supplements can also interact with medicines. That's why it's worth having your diet, symptoms and, where needed, blood results looked at properly before you start.

Bringing food back to the centre

If you'd like to put food back at the heart of your health, start simply:

• Eat the rainbow. Different colours mean different plant compounds. Aim for something red, orange, yellow, green and purple through the week.
• Count plants, not calories. Try to eat 30 different plant foods a week, counting vegetables, fruit, beans, lentils, whole grains, nuts, seeds, herbs and spices.
• Choose whole over juiced. Eat your fruit rather than drink it.
• Add fibre gradually. Beans, lentils, oats and vegetables, increased a little at a time, with plenty of water.
• Pair foods wisely. A drizzle of olive oil on your salad or vegetables helps your body take in more of their goodness.

At Rootwise, food always comes first. In a consultation we look at what you eat, how you feel and, where it helps, what your test results show, and build a plan around real food, with supplements only where they're truly needed.