Yet another sizable study has shown that common dietary supplements have little to no effect on late life mortality. This finding of course has to compete with the wall to wall marketing deployed by the supplement market. Researchers have been presenting data on the ineffectiveness of near all supplements of years, but it doesn't seem to reduce the enthusiasm for these products. In the past it was fairly easy to dismiss all supplements as nonsense, or at the very least causing only marginal effects that were in no way comparable to the benefits of exercise and calorie restriction, but matters are now becoming more complex. New supplements based on altered mitochondrial biochemistry or senolytic activity, such as nicotinamide riboside, mitoQ, and fisetin, might well have effect sizes that are worth it as an addition to calorie restriction and exercise; we shall see as human studies progress.
In a massive new analysis of findings from 277 clinical trials using 24 different interventions, researchers say they have found that almost all vitamin, mineral, and other nutrient supplements or diets cannot be linked to longer life or protection from heart disease. Although they found that most of the supplements or diets were not associated with any harm, the analysis showed possible health benefits only from a low-salt diet, omega-3 fatty acid supplements and possibly folic acid supplements for some people. Researchers also found that supplements combining calcium and vitamin D may in fact be linked to a slightly increased stroke risk.
Surveys show that 52% of Americans take a least one vitamin or other dietary/nutritional supplement daily. An increasing number of studies have failed to prove health benefits from most of them. "The panacea or magic bullet that people keep searching for in dietary supplements isn't there. People should focus on getting their nutrients from a heart-healthy diet, because the data increasingly show that the majority of healthy adults don't need to take supplements."
The vitamin and other supplements reviewed included: antioxidants, β-carotene, vitamin B-complex, multivitamins, selenium, vitamin A, vitamin B3/niacin, vitamin B6, vitamin C, vitamin E, vitamin D alone, calcium alone, calcium and vitamin D together, folic acid, iron and omega-3 fatty acid (fish oil). The diets reviewed were a Mediterranean diet, a reduced saturated fat (less fats from meat and dairy) diet, modified dietary fat intake (less saturated fat or replacing calories with more unsaturated fats or carbohydrates), a reduced fat diet, a reduced salt diet in healthy people and those with high blood pressure, increased alpha linolenic acid (ALA) diet (nuts, seeds and vegetable oils), and increased omega-6 fatty acid diet (nuts, seeds and vegetable oils). Each intervention was also ranked by the strength of the evidence as high, moderate, low or very low risk impact.
The majority of the supplements including multivitamins, selenium, vitamin A, vitamin B6, vitamin C, vitamin E, vitamin D alone, calcium alone and iron showed no link to increased or decreased risk of death or heart health. "Our analysis carries a simple message that although there may be some evidence that a few interventions have an impact on death and cardiovascular health, the vast majority of multivitamins, minerals and different types of diets had no measurable effect on survival or cardiovascular disease risk reduction."