Can Selenium Supplementation Cut Body Fat?

Could selenium play a role in helping patients lose weight?

The prevalence of overweight and obese adults has increased 27% worldwide since 1980. With global obesity costs estimated at $2 trillion, plus 3 million related deaths each year, new insights into healthy weight maintenance are crucial.

A recent study published in Nutrients considered the role of selenium, an essential trace element, in weight management.

Found in Brazil nuts, seafood, meat, chicken, eggs, and brown rice, selenium is a factor in reproduction, thyroid hormone metabolism, and protection against oxidative stress and inflammation. Now, the new study suggests that there may be an association between selenium-rich diets and lower body fat percentages.

Researchers examined the relationship between dietary selenium intake and obesity in 3214 subjects. These participants completed the Willett food frequency questionnaire to estimate their daily intake of selenium (measured as micrograms/kilogram of body weight/day). The researchers also measured participants’ body composition using dual-energy X-ray absorptiometry.

The results showed a dose-dependent relationship between higher dietary selenium intake and lower body mass index, waist circumference, and trunk, android, gynoid, and total body fat percentages. This relationship was independent of age, total dietary calorie intake, physical activity, smoking, alcohol, medication use, and menopausal status.

The study authors estimated that dietary selenium intake may account for 9% to 27% of the variation in subjects’ body fat percentages.

In previous studies of rats, selenium supplementation caused significant weight and body fat reduction. However, 2 small interventional studies in humans have reported contradictory results.

One study of 11 men found that raising selenium intake increased weight gain. Another study of 24 participants found that consuming selenium-enriched chicken had no impact on weight loss.

While this current study had a much larger sample size, its design could not prove cause and effect. Additionally, since only dietary selenium intake was studied, the usefulness of selenium supplementation remains unclear.

Further research is needed for a complete understanding of selenium’s impact on body fat composition.