Eliseo Guallar of the Johns Hopkins Bloomberg School of Public Health in Baltimore and colleagues wrote in a editorial "Enough is Enough: Stop Wasting Money on Vitamins and Mineral Supplements," which accompanied the studies in the Annals of Internal Medicine, said there is no clear evidence of a beneficial effect on all-cause mortality, cardiovascular disease or cancer.
Dietary supplements may help some people meet nutritional needs, but eating a wide variety of nutrient-rich foods is the best way for most people, the studies said.
"These findings support the evidence-based position of the Academy of Nutrition and Dietetics that the best nutrition-based strategy for promoting optimal health and reducing the risk of chronic disease is to wisely choose a wide variety of foods," Heather Mangieri, registered dietitian nutritionist and academy spokeswoman for the Academy of Nutrition and Dietetics, said in a statement.
"By choosing nutrient-rich foods that provide the most nutrients per calorie, you can build a healthier life and start down a path of health and wellness. Small steps can help you create healthy habits that will benefit your health now and for the rest of your life."
The academy's position on supplements also acknowledges that nutrient supplements may be necessary in special circumstances. "Additional nutrients from supplements can help some people meet their nutrition needs as specified by science-based nutrition standards such as the Dietary Reference Intakes," Mangieri said.
Mangieri offered tips for developing a nutrient-rich eating plan:
-- Start each day with a healthy breakfast that includes whole grains, fat-free or low-fat dairy for calcium and vitamin D, and vitamin C-rich foods.
-- Replace refined grains with whole grains like whole-grain breads and cereals and brown rice.
-- Pre-washed salad greens and pre-cut vegetables make great quick meals or snacks.
-- Eat fresh, frozen or canned (without added sugar) fruit for snacks and desserts.
-- Include at least two servings of omega-3 rich seafood per week.
-- Don't forget beans, which are rich in fiber and folate.
The recent increase in sales of supplements may not have been accompanied by an increase in consumers' knowledge about what they are taking, the academy said.