Amid all the conflicting reports advising us to eat this but not that, to avoid this food and bulk up on that one, one fact is indisputable. To live, we need to eat.
If we stop eating for long periods, bad things happen to us. We need food’s energy and nutrients to keep our muscles working, our neurons firing and our cells plumped up and healthy, with all the necessary chemical signalling happening in our tissues that maintains our systems.
But let’s qualify the truism. What we really need for health is to eat adequate amounts of nutritious food.
A study published last year in the prestigious medical journal The Lancet determined that, in 2017, one in five deaths — 11 million deaths in total — and 255 million lost years of healthy life were linked to poor diet. Too much salt contributed to three million deaths, not enough whole grains and fruit contributed to three million and two million deaths respectively.
In North America, those same issues with salt, whole grains and fruit exist, but the study also identifies too few fresh vegetables, nuts and seeds, and too much processed meat as contributing to far too many illnesses and deaths.
If we ate better — not necessarily more — as many as 52,000 deaths and 1.16 million years of illness in high-income, privileged North America could have been avoided.
If that happened, food could be one of the best medicines around.
In treating food as medicine, however, some people take the next step and resort to supplements. Health Canada reports that 15.7 million Canadian routinely used at least one nutritional supplement in 2015.
The rationale is twofold. Some people believe if a little bit of a nutrient is good, more must surely be better. Others rely on multivitamin pills to compensate for the inadequacies of their diet, sleep or exercise.
However, more and more evidence shows that approach might be misguided.
One study, published in the Annals of Internal Medicine last year, shows that adequate intake of certain nutrients is linked to fewer deaths when the nutrients come from food — but not when the nutrients come from supplements. The researchers also found that calcium intake in excess of 1,000 mg/day from supplements might increase risk of death from cancer, whereas when calcium was obtained solely from food, no association with increased cancer death risk emerged.
Two studies in the late 1980s that were designed to uncover how beta-carotene lowers lung-cancer risk had to be suspended because the opposite results started happening in significant numbers — over time, more study participants taking the supplements suffered lung cancer compared with participants taking the placebos. A 2007 analysis of more than 65 randomized trials revealed a five per cent increase in risk of death in supplement-taking participants versus the placebo-ingesting groups. A 2018 analysis of research involving 450,000 people found that multivitamins did not reduce risk for heart disease, while a 2019 analysis of 21 clinical trials looking at more than 80,000 patients showed that taking vitamin D supplements didn’t lower risk of heart attack or stroke. And a 12-year study of 5,947 men found multivitamins did not reduce their memory loss over time.
And so on.
Some circumstances do warrant supplements — for example, pale-skinned people who live in high latitudes and spend much of their time indoors and away from windows may benefit from low doses of vitamin D in winter or fog-filled months, and pregnant women who have difficulty accessing or keeping down leafy greens might want to talk to their doctors about folic acid supplements.
Fruits, vegetables, nuts, grains and healthy fats contain more nutritional punch in broad-spectrum combinations and at safer doses than high-concentration supplements do. They also come with built-in fibre to scrub the digestive plumbing, absorb toxins and help prevent disease. The substances found naturally in whole foods also feed health-supporting microbes in our guts and provide protection against high blood pressure, high blood sugar and inflammation.
Nothing replaces a healthful diet. And a healthful diet combined with a healthy — low-stress, active, well-rested, socially connected — lifestyle can provide the best ingredients of all for health.