Dietary supplements and health outcomes
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Dietary Supplements and Health Outcomes: Global Use and Targeted Benefits
Dietary supplements are widely used around the world, often with the goal of improving health or preventing disease. Their benefits are most clear when used to address specific nutrient deficiencies, such as vitamin A and iron in developing countries, folic acid for women of reproductive age, and vitamin D and calcium for bone health in older adults. In these cases, supplements can help meet nutritional needs and reduce the risk of deficiency-related health problems, especially in vulnerable populations 157.
Dietary Supplements and Chronic Disease Prevention
The evidence for dietary supplements in preventing chronic diseases like cardiovascular disease (CVD) and cancer is mixed and often inconclusive. Large-scale reviews and meta-analyses have found that most supplements do not significantly reduce the risk of all-cause mortality, CVD, or cancer in the general population. Some exceptions exist: vitamin E supplements have shown a small reduction in cardiovascular mortality, and folic acid may lower CVD risk. However, other supplements, such as vitamin A and high-dose beta-carotene, have been linked to increased cancer risk and higher all-cause mortality, particularly in certain groups like smokers 2369.
Supplement Use, Lifestyle, and Diet Quality
People who use dietary supplements often have healthier lifestyles overall—they tend to be older, have lower body mass index (BMI), smoke less, exercise more, and eat healthier diets compared to non-users. However, studies show that supplement use does not necessarily lead to better diet quality, as many individuals may use supplements as a substitute for improving their food choices rather than as a complement 48.
Nutritional Supplements in Older Adults and At-Risk Populations
In older adults and those at risk of malnutrition, specialized oral nutritional supplements (ONS) can improve nutritional status, body weight, and some functional outcomes, such as muscle strength. These benefits are most pronounced when supplements are combined with dietary counseling. In hospitalized or community-dwelling elderly populations, supplementation has been shown to reduce the risk of developing malnutrition and may lower mortality rates in those who are initially well-nourished 57.
Risks and Considerations of Dietary Supplement Use
While supplements can be beneficial for those with specific deficiencies, their use in healthy individuals for disease prevention is not generally supported by strong evidence. High doses of certain supplements can be harmful, and some products may be adulterated or sold illegally, increasing the risk of adverse events. It is important that supplement use, especially in high doses or for chronic disease prevention, be guided and monitored by healthcare professionals 1236+1 MORE.
Conclusion
Dietary supplements play a valuable role in addressing nutrient deficiencies and improving health outcomes in at-risk populations, such as the elderly or those with poor nutrition. However, for the general population, routine use of supplements for chronic disease prevention is not supported by consistent evidence and may carry risks, especially at high doses. Improving overall diet quality through food choices remains the most effective strategy for promoting long-term health. Supplement use should be targeted, evidence-based, and, when possible, supervised by healthcare providers.
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