We sure love popping pills.
In the last two decades, popular culture has decreed that three basic meals a day isn’t enough: modern-day healthy living needs something more – supplements. Despite a global economic downturn, the world’s appetite for dietary supplements remains insatiable; every year we collectively swallow over fifty billion dollars of minerals, vitamins and weird herb extracts.
Stepping into the Aladdin’s treasure trove of weight-loss berries, anti-cancer honeys and natural pain-fighting remedies (that is your local health food store) how do we know which (if any) actually work? Often endorsed by high profile celebrities and glossy magazines – I’m in pursuit of finding out which actually do anything useful...
Do Dietary Supplements Work?
Finding out the truth behind supplement hype is a bit like the apple-bobbing: the moment you think you getting a bite of something good, it slips away leaving you with the lingering taste of insipid water. There’s a bewildering array of misinformation, marketing spin and downright lies. Most research isn’t very good, and worse, much is funded by the supplement manufacturers – keen to prove their supplement will help change lives.
On this proviso, I endeavour to give a fact-based overview of the five best selling supplements in health food stores today. So according to current market research, here’s the top five rundown of most popular dietary supplements – and whether they actually work:
It has garnered a fervent following from previously stiff-limbed fans desperate for relief from a condition that has no cure. Many people swear that glucosamine has done amazing things for their joints; and it’s difficult to argue with someone who says it has made them “feel twenty years younger”.
Although some doctors still prescribe it, unfortunately the general consensus is that it doesn’t work. Tit-for-tat research over the years has shown that it works, then it doesn’t, then it does – but the last three years have yielded comprehensive conclusions (meta-analyses) that have shown that glucosamine works no better for arthritis than a dummy pill.
Is it Worth it? Glucosamine supplements almost certainly doesn’t cause harm, but they are unlikely to help your joints much either.
Extra reading: Effects of glucosamine, chondroitin, or placebo in patients with osteoarthritis of hip or knee: network meta-analysis - large review of all available blinded trials that concludes: “Compared with placebo, glucosamine, chondroitin, and their combination do not reduce joint pain or have an impact on narrowing of joint space. Health authorities and health insurers should not cover the costs of these preparations, and new prescriptions to patients who have not received treatment should be discouraged.”
4. Omega 3 Supplements
The Western World has gone a bit omega-3 mad. A Supplement that sounds like the home of the Klingons has appeared on milk, eggs and bread packaging. Most of us haven’t a Scooby Doo as to what it is, less whether it’s worth buying.
Ignore the media hype – omega-3 is infinitely crucial for the brain, heart and immune system to function normally. It is an ‘essential fat’ that we must have in our diet and surveys show that nine out of ten of us don’t get enough of this in our normal intake. Taking an omega-3 supplement (or that pricey spread emblazoned with “contains Omega 3”) would therefore sound like a sensible idea. However, a good diet could do just the same thing: eating two to four portions of fish a week (one of which is oily) will be more than enough to keep you topped up on omega-3.
For people recovering from a heart attack or heart disease, omega-3 is vital – and supplements have been shown to aid recovery. So those of us who can’t handle the fish. a capsule will clearly benefit.
Buyer Beware: There are many cheap supplements that have poor quality ingredients. Always check the packet to make sure it contains ‘EPA and DHA’ – a marker of sufficient quality. Also check how much it contains – recommend doses are 500mg – 1,000mg a day.
Worth it? People with heart problems should definitely make sure they get enough Omega 3 fats. For the rest of us, eating more fish (as part of a balanced diet) could be a better route to a healthier body.
Update: Since this article was first posted, more research has been published. A large review of available evidence recently published in the Journal of the American Medical Association concluded that omega 3 supplementation “was not associated with a lower risk of all-cause mortality, cardiac death, sudden death, myocardial infarction, or stroke based on relative and absolute measures of association.” A separate study in the Journal of the National Cancer Institute has found a statistically significant link between omega 3 supplementation and prostate cancer.
There is good evidence to show that omega 3 supplements can reduce inflammation (see this thorough meta-analysis published in 2012 in the British Journal of Nutrition) and may be useful in the treatment of inflammatory conditions (such as rheumatoid arthritis). There is some evidence that omega 3 may help reduce muscle soreness after exercise, although there is conflicting research. It is generally advised to avoid omega 3 supplementation unless under the guidance of a doctor.
3. Cod Liver Oil
If you’re old enough, you’ll remember mother force feeding you a spoonful of this vile tasting fish syrup each morning. It’s a remedy as old as the hills (well, at least 300 hundred years old) – but are its healing powers a load of codswallop?
Traditionally used for ‘rheumatism’ – the jury is still out as to whether cod liver oil really does help aging joints. It is chock-full of omega-3, vitamin A and D and one thing is for sure – if today’s youngsters were still getting their daily dose then their bones would be stronger. Recent years has seen the re-emergence of kid’s bendy-bone disease – Rickets. Caused by a lack of sunlight and oily fish; cod liver oil will provide the essential vitamin D needed for healthy bones.
Worth it? Good for bones and (and possibly preventing cancer) – a regular intake of oily fish and sunlight is a probably a better alternative than a supplement. Failing that, an odourless capsule would suffice – but always avoid a supplement in pregnancy. Also, check the dosage (especially in children) – as it is quite easy to overdose on Vitamin A.
Update: Since this article was published in 2011, more research has come to light. The National Institute of Health have compiled a very comprehensive review of the available research (click here) highlighting that fish oils can be helpful in helping in controlling cholesterol levels. Note the evidence levels for other conditions and whether taking fish oils can interfere with prescribed medications.
2. Vitamin C
Few people ever win a Nobel Prize. Linus Pauling had won two and was after his third. In the 1970s, he made the claim that large vitamin C doses would treat anything from cancer to the common cold. Forty years later, we can (with a fair degree of certainty) conclude that this great polymath was quite wrong. All the better that he never won his third Nobel Award then…
Eating oranges have become synonymous with stopping a cold – although in reality chomping through the citrus is unlikely to help much. The best research has shown that vitamin C supplements help fight off a cold, but can’t stop you getting it in the first place. The benefit of vitamin C seems to be best for those who live on the edge – extreme athletes and sportspeople who are constantly pushing their body to its limits. For you and I, vitamin C may reduce the length of the sniffle and headache, but only in some hefty doses (more than you’ll ever get from eating oranges). But be advised, more than 500mg in one dose could give you some rather uncomfortable side effects.
Worth it? Nearly every Westerner’s diet has enough vitamin C in it for good health – so there’s no need to go worrying about scurvy. Taking extra vitamin C is safe (except in the very highest doses) but unlikely to give any life-changing benefit.
Smoker? If you smoke – you really ought to take extra vitamin C (or quit!). Those cancer sticks burn up vitamin C faster than your bank balance – and 2000mg of Vitamin C a day is called for.
One tablet does it all – so why bother with separate tablets when a multivitamin tablet could do the job?
For many years, many physicians and fitness experts have advised a multivitamin to ensure you meet your daily healthy requirement of all the basic vitamins and minerals.
It makes a huge amount of sense given the odd diets many of us have, but as with most dietary supplements – evidence for its effectiveness is distinctly lacking.
Worth it? It makes logical sense, but large-scale trials fail to show any real benefit for most people in taking a multivitamin tablet.
But Supplements are Good for some people
These article draws upon research based on statistics of large numbers of ‘normal’ people. Many of us (such as those with cancer, pregnant women, and the elderly) may benefit from nutritional supplements. If you have a medical condition, it is always worth consulting a medically trained professional to see if any dietary changes may benefit you.
Why do people still take supplements?
It’s difficult to explain why so many people take supplements, when the evidence for their efficacy is so lacking.
Much of the purported benefit may be explained by the placebo effect, which is eloquently explained in this video:
Now, I can’t claim to have all the answers. Advocates of alternative therapies will be quick to point out that scientific studies have their limitations – namely that randomised trials assume that all humans are physiologically the same and may overlook more subtle effects.
Science has its limitations, but I believe it is the best we have. Given the amount of profiteering done by ‘healthy living’ companies who cash in on our want to live long and healty, I’d always suggest hunting down the facts than making a decision from hearsay…
Thanks for reading – comments and feedback are warmly welcomed! Opinions expressed are my own…
BORED WITH SCIENCE WRITING? I was – but I’ve been lucky enough to part of a team that has launched a free, bi-monthly digital magazine which tries to deliver understandable science writing. It’s also about giving new or undiscovered writers a chance to write to a growing audience of readers. Why not check it out here! I think it’s rather cool…
Always consult a medical professional before taking any nutritional supplement. Some supplements can have adverse effects in some individuals and may interact with existing medications.
SELECTED REFERENCES: (there are plenty more!!)
Heimer, K., Hart, A., Martin, L., & Rubio-Wallace, S. (2009). Examining the evidence for the use of vitamin C in the prophylaxis and treatment of the common cold Journal of the American Academy of Nurse Practitioners, 21 (5), 295-300 DOI: 10.1111/j.1745-7599.2009.00409.x
Mintel Market Researc (2011) Vitamins and Supplements – UK – September 2011. Mintel Group: London.
Wandel, S., Juni, P., Tendal, B., Nuesch, E., Villiger, P., Welton, N., Reichenbach, S., & Trelle, S. (2010). Effects of glucosamine, chondroitin, or placebo in patients with osteoarthritis of hip or knee: network meta-analysis BMJ, 341 (sep16 2) DOI: 10.1136/bmj.c4675
Huang HY, Caballero B, Chang S, Alberg A, Semba R, Schneyer C, Wilson RF, Cheng TY, Prokopowicz G, Barnes GJ 2nd, Vassy J, & Bass EB (2006). Multivitamin/mineral supplements and prevention of chronic disease. Evidence report/technology assessment (139), 1-117 PMID: 17764205
Douglas, R., & Hemilä, H. (2005). Vitamin C for Preventing and Treating the Common Cold PLoS Medicine, 2 (6) DOI: 10.1371/journal.pmed.0020168