According to Statistics Canada, 45 per cent of Canadians use nutritional supplements (vitamins, minerals, multivitamins, fibre supplements or fish and other oils high in omega-3 fatty acids) on a daily basis. That figure increases dramatically in people aged 51 to 70 years, with almost two-thirds of women and 42 per cent of men in that age group using supplements.
Since writing “What you need to know about nutritional supplements” in this column three years ago (March 4, 2015), more scientific studies have been conducted to identify what, if any health benefits, supplementation provides. The conclusion is still that there are no measurable health benefits for healthy people who take vitamins or multivitamins. https://tinyurl.com/ybjtkbkl
A 2017 study published in the Journal of Nutrition found that “there’s no conclusive evidence that dietary supplements prevent chronic disease in the average person.” https://tinyurl.com/y8smzelk
The use of supplements “is not justified and they should be avoided. This message is especially true for the general population with no clear evidence of micronutrient deficiencies, who represent most supplement users in the United States and in other countries.” https://tinyurl.com/yaxdpd3n
Despite the many problems with the average Western diet (high in sodium, sugar, saturated fat and calories), it tends to provide sufficient vitamins and minerals for the average person, especially since many food products such as flour, milk and salt are fortified with vitamins and minerals.
Only a quarter of supplement consumers do so on the advice of their doctor. What’s the harm of taking supplements when you don’t have a nutritional deficiency? Besides being a waste of money, some supplements can be harmful especially when taken in large doses. For example, vitamin E used to be recommended for heart protection, then it was discovered that vitamin E can increase the risk of prostate cancer and heart disease. Studies found that beta carotene pills increased the rate of lung cancer. Similarly, calcium supplements were once highly promoted as a preventative strategy for osteoporosis; more recent findings are that calcium supplements increase the risk of kidney stones and heart disease.
The use of some supplements has declined as certain ones have fallen out of favour, but more people than ever are taking fish oil and vitamin D. Fish oil supplements are touted as a strategic tool to prevent heart attacks, some cancers and even dementia, but there isn’t yet any substantial scientific support. Eating fish a couple of times per week instead of eating less healthy foods is considered a sensible choice for reducing risks and studies suggest that the behaviour of replacing junky meals such as burgers and pizza with a healthier choice of fish (not fried) – not necessarily the consumption of omega-3 in the fish – reduces the risk of various diseases.
Clinical trials of vitamin D for falls prevention in seniors have had contradictory findings; investigation is ongoing. However, for many supplements, the lack of benefits and/or potential harm is clear and further investigation is unjustified.
Vitamin supplements may be recommended for some populations and contraindicated for others. For example, folic acid is important for women who are pregnant or planning on getting pregnant; but it has no proven benefits for older adults and studies show it increases their risk of cancer.
When it comes to access to supplementation, there’s a health disparity in North America. People who take vitamins tend to be more educated, have higher incomes and live a healthier, more active lifestyle; these factors tend to reduce their risks for heart disease and cancer whether or not they take vitamins. Low-income Canadians are less likely to take supplements even though their diets may not be as balanced and they are more likely to have nutritional deficiencies.
Are you the type of person who tends to jump on the bandwagon when you hear of possible health benefits of supplements? Are you taking a multivitamin to combat your suboptimal diet or as an insurance policy? Proactive behaviour is a good thing but it’s wise to get the facts. Eating better – even small improvements – and exercising may be your best strategy. Don’t waste your time and money taking supplements that are ineffective or potentially harmful. Don’t get your “facts” from magazines at the checkout aisle or people whose objective is to sell supplements whether you need them or not. Talk to your medical doctor about whether you need testing for nutritional deficiencies and to discuss the pros and cons of any supplements before you add them to your daily regimen.