Dietary supplements and disease prevention - a global overview

Area of Science:

• Nutrition Science
• Public Health
• Preventive Medicine

Background:

• Inadequate nutrition and micronutrient deficiencies are significant global health concerns.
• Dietary supplements and food fortification can address nutritional gaps, especially in vulnerable populations.
• The efficacy of supplementation is debated, particularly for high-dose, individual micronutrients in well-nourished individuals.

Purpose of the Study:

• To summarize the health outcomes associated with dietary supplements.
• To guide decisions on dietary supplement recommendations in both developing and developed countries.
• To highlight the importance of baseline nutrition in determining supplementation effectiveness.

Main Methods:

• Review and synthesis of existing literature on dietary supplements and health outcomes.
• Analysis of supplementation strategies for specific micronutrients (e.g., vitamin A, iron, folic acid, vitamin D, calcium).
• Consideration of supplementation effects across different populations and nutritional statuses.

Main Results:

• Targeted supplementation (e.g., vitamin A, iron, folic acid, vitamin D, calcium) can address specific deficiencies in at-risk groups.
• Low-dose daily multivitamin supplementation showed potential benefits, including reduced cancer and cataract incidence in men.
• The impact of dietary supplements is influenced by baseline nutritional status and population needs.

Conclusions:

• Dietary supplements offer potential health benefits when appropriately targeted to correct deficiencies.
• Individual high-dose micronutrient supplementation lacks consistent evidence for chronic disease prevention in well-nourished populations.
• Baseline nutrition is a critical factor modulating the effects of dietary supplements on health outcomes.