How do we know if supplements actually make a difference?

    30 March 2016

    Vitamin and mineral supplements have been around for over a century now and, for some, they have become an integral part of a healthy life. Yet there is a paradox about who takes them. It seems the majority of users generally already have a good diet — that’s to say, they eat modest amounts of lean protein, nuts and seeds, fruits and vegetables, legumes and dairy. They are likely to be physically active and are unlikely to be obese. In short, the majority of people who take supplements are the very ones who have the least need, whereas their counterparts who have a poor diet, are overweight and inactive are the least likely group to take any vitamin supplements.

    The truth is that in the majority of cases we don’t ‘need’ them and can function without them. However, there are potential benefits to be had by taking the appropriate supplements at the ideal dose and for the optimum length of time.

    You’d think that the biggest problem would be finding an impartial professional who can guide you as to which, how much and for how long. But no, the most confusing part of the debate is how on earth do you know if what you are taking is actually working.

    Some supplements might be taken for chronic conditions, such as joint ache. On experiencing ongoing inflammation one might take, say, a supplement of omega-3 and another of turmeric. Give it a few days and the inflammation might be reduced. Stop taking the supplements and the discomfort returns, and there is your anecdotal proof that essential fats and turmeric reduce inflammation. Of course the condition might have been triggered by other factors, which a few days’ rest and the inbuilt abilities of the human body to repair itself took care of. The timing of the supplements might have been merely coincidental and thus taking them in the very long term would be wasteful.

    The same is true of the common cold — at the first sniffle you might take a combination of zinc, vitamin C, echinacea, bee propolis and elderberry and do so religiously for a few days until the cold passes. The likelihood is that you will slow down a little at the same time, cancelling social arrangements and getting more rest. Or instead you might have simply slowed down, not taken any supplements, preferring paracetamol and fluids instead, and the cold would have passed too. Did the supplements do anything aside from give one a sense of involvement?

    Then there is the issue of supplement guilt. You don’t have to subscribe to health magazines to read health advice these days, as lifestyle information is widespread. Features and comments about which supplements to take are commonplace, often driven by marketing and PR, hence being found in the colour supplements more often than on the science pages of broadsheets. To my mind these articles carry the same message, which is that unless you take X supplement then you have a greater risk of Y illness and it will be Your Fault. The more susceptible amongst us might easily be persuaded to take whatever supplement it is in the long term largely motivated by fear.

    Supplements don’t come cheap. I checked the packaging on a mid-range omega-3 capsule offering 1,000 mg of fish oil. The instructions suggested one to three capsules a day. At the upper end this would cost around £109 a year. Surely this is a small price to pay for the wealth of potential benefits? A quick search online will suggest that omega-3 is linked to dementia, Alzheimer’s, asthma, arthritis, depression, dry skin, bipolar disorder, cardiovascular disease and blood pressure. Interestingly, out of all the claims made about omega-3 fats, the EU has only authorised claims about cardiovascular health and blood pressure, suggesting that the claims for the other conditions were not backed up by what the committee viewed as robust research.

    Now try vitamin C. Then zinc. Or magnesium. Probiotics. What about selenium? The list of endless as someone somewhere will have an argument for taking nearly every nutrient. Thus the £109 a year could end up as several thousand. It is all too easy to feel pressured into taking a multitude of supplements to avoid illness and conditions that you might never have got in the first place.

    That’s not to say that one shouldn’t take supplements or indeed that anyone who does has somehow been misled or duped. But short of making a clone of oneself — one of whom eats well, takes supplements, exercises, rarely drinks and has plenty of rest interspersed with mindful meditation, while the other version whoops it up with fats, refined sugars, alcohol and inactivity — how will we know if it’s all worth it?

    I am reminded of a cartoon, a series of images depicting two elderly men sitting in chairs at a rest home, wizened and bent over, drool on their chins. The sun rises and sets in the background. At the end of the day one raises his head and says: ‘You know, if I’d smoked and drunk I’d have missed all this.’