Call Us +852 3113 1331

The Great Supplement Debate

Posted on Feb 17, 2014 by Sergio Ulloa ()  | Tags: multivitamins, health benefits of vitamins, vitamin A and cancer, iodine deficiency, iodine and cancer, omega-3 fatty acids, omega oils, zinc for common cold, vitamin C for cold

It’s that time of year again, when we look back at the previous weeks of holiday excess and over-indulgence and determine to make good some of the bad habits we’ve acquired. While we may not be looking to be bikini-ready just yet, nonetheless, the new year represents a concerted push to do better, from a health perspective at least. The start of a new year is a good time to be a nutritional supplement manufacturer.

According to Euromonitor, a market intelligence firm, the global multivitamin and supplement industry is worth almost US$70 million globally. With the double edged sword of an increasingly sedentary lifestyle and greater awareness that cardiovascular disease and cancer are the leading causes of death in most developed countries, it’s hardly surprising that around half of all Americans take some form of multivitamin or supplement, believing that they’re doing the right thing. But are they?

Not necessarily, according to a hefty report recently published in the highly influential journal Annals of Internal Medicine, which looked at the effectiveness of supplements in the prevention of chronic disease. The report evaluated two new studies and a thorough meta-analysis of almost 30 other studies, focusing on the effects of taking supplements on cardiovascular disease (CVD) and cancer among participants. The findings found “limited evidence” to “support any benefit from vitamin and mineral supplementation for the prevention of cancer or CVD.” While overall the findings found “no consistent pattern of harms from nutritional dosages of multivitamins” the trial findings demonstrated only borderline positive benefits, and only on cancer rates in men. Supplements were found to have no effect on CVD rates at all.

Vitamin A And Cancer – An Unhealthy Alliance?

However, the Annals of Internal Medicine study did reveal evidence to suggest that certain supplements may be more harmful for us than previously believed. Vitamin A deficiency is one of the world’s top three nutritional deficiencies, and yet vitamin A also has potentially harmful consequences if taken in excess. Its effects have been well documented in relation to birth defects in developing fetuses, but more and more research is pointing to its cancer-causing potential too. The Annals of Internal Medicine report re-highlighted findings that taking vitamin A and B-carotene supplements actually increase lung cancer risk in smokers. Indeed, one major trial referenced extensively in the report found alarmingly higher rates of melanoma among women taking antioxidant supplements and concluded, “antioxidant supplementation, especially with β-carotene, may have potentially harmful effects.”  The thinking goes that the excess ‘good’ antioxidants interfere with the cell’s natural - and necessary - life cycle and ultimate death, causing the cell to continue reproducing, eventually becoming cancerous. The conclusion suggests that, while antioxidants are still vital for mopping up the bad stuff, it seems you really can have too much of a good thing, and a little free-radical activity is actually beneficial for us after all.

Another trial referenced in the study found that menopausal women taking vitamin A were more likely to suffer hip fractures than those who didn’t. And if that wasn’t enough for women with low bone density issues, another separate and recent analysis published by the U.S. Food and Drug Administration stopped just short of issuing specific recommendations on the long-term use of bisphosphonates, or ‘bone-building’ drugs, because of the growing body of research that links prolonged use with an increased risk of atypical thigh bone fracture, femur fracture and in rarer but more serious cases, esophageal cancer.

Unsurprisingly the Annals’ findings have divided the medical community: some critics slam the trials as being unrepresentative of the average American’s (not so great) diet, and argue supplementation is absolutely necessary in cases of nutritional deficiency or in pregnancy. For example, one trial found that calcium supplements, when taken with vitamin D, actually decreased cancer risk in women, thus highlighting the possible synergistic benefits of certain vitamins. Critics noted other data inconsistencies as well. Although the report found no overall evidence to support the theory that selenium is beneficial in preventing cancer, nonetheless one trial did report a decreased risk in cancer rates with those who took selenium.

So Where Does This Leave Consumers?

Much of these findings bear out the old common sense adage that, essentially, you are what you eat, so you should eat well: plenty of fresh fruit, vegetables, fish and complex carbohydrates. With a balanced diet, it’s fairly likely you’re going to service your body nutritionally without the need for excess supplementation. Of course, this only works if you are able to stick to a good diet all the time. Unfortunately, statistics indicate that chronic disease and nutritional deficiencies are sharply on the rise globally. And while for many of us taking a multivitamin could be a convenient way of sidestepping the salad issue, the research from the Annals of Internal Medicine indicates that preventative health measures in the form of pills aren’t very much help at all. So what, if any, supplements should we be taking?

Omega Oils – The No Brainer Brain Food?

Most people will be familiar with omega oils - or omega-3 fatty acids - and may know that they are largely found in oily fish such as mackerel, herring and tuna, and some plants such as flax seed. What many people don’t realise is that although our bodies need these essential fatty acids for a healthy cardiovascular system, cells and joints, we are not able to produce them ourselves and so we must acquire them from the food we eat. While the evidence to convincingly support omega oil’s function as ‘brain food’ is still in debate, these oils are incredibly important to our overall health and if you aren’t eating oily fish a minimum of twice a week - and let’s face it, that’s probably most of us - then it’s a good idea to start supplementing, particularly those who have already suffered a heart attack.

The Cold War – Vitamin C Versus Zinc

A well-known hazard of winter is the common cold, and if those first sniffles have you reaching for ultra strength vitamin C, it might be worth noting that science has pretty well trounced the notion that there is anything to be gained from vitamin C supplements as a preventative for a cold, other than vividly coloured pee and perhaps a few dollars down the toilet. There is some limited evidence to show that vitamin C may reduce the length of a cold, particularly in children, but overall the scientific evidence is sketchy at best. Zinc, however, does appear to have a positive outcome on the duration and severity of a cold, and a 2011 study by the Cochrane Collaboration concluded that regular zinc supplements appeared to protect people, and particularly children, from catching regular colds. Again, the jury is still out on the synergistic efficacy of vitamin C when taken with zinc, but for repeat cold sufferers a daily dose of zinc might be just the ticket.

To conclude, healthy adults enjoying a balanced diet, free from refined sugars and simple carbohydrates, shouldn’t require excess nutritional supplementation, but for various reasons, some people do. Children aged between six months and five years, for instance, should be given a supplement containing vitamins A, C and D, and pregnant women or those actively trying to conceive should take folic acid in order to prevent neural defects. People who suffer from hereditary conditions that prevent absorption of critical nutrients will clearly benefit from additional supplementation, too.  Every person has individual health and lifestyle requirements, and while there is a division of professional opinions on the efficacy of multivitamins, there is also no clear-cut evidence to suggest that supplements do any harm either. While studies err on the side of caution when it comes to self-administration of supplements, many in the healthcare industry still advocate the use of vitamins in preventing or fighting cancer or chronic disease.

As always, knowledge is power, and consulting a physician or a holistic healthcare practitioner is the first step before embarking on any supplementation regime. Read up on the subject and be aware of what your body is telling you. Persistent, nagging and minor irritations and ailments may be a sign you are deficient in some area and supplementation may indeed be of benefit to you, but adjusting your diet accordingly is a good first port of call, too.

Alternative health practitioners can offer blood tests to ascertain certain deficiencies, although it’s worth noting many such tests won’t be able to pinpoint certain deficiencies, such as omega-3 fatty acids, so you’ll need to take a really honest look at your diet and lifestyle. Google any relevant health studies and read up online. Armed with this knowledge it’s then far easier to make informed choices about what’s best for near, and long term, health prospects.

And finally: don’t forget to eat your greens.


Be Sociable, Share!