Phosphate supplementation prevents a decrease of triiodothyronine and increases resting metabolic rate during low...

Area of Science:

• Human Nutrition
• Metabolic Studies
• Endocrinology

Background:

• Obesity management often involves low-energy diets.
• The role of mineral supplementation in weight loss programs requires further investigation.
• Thyroid hormones play a crucial role in regulating metabolic rate.

Purpose of the Study:

• To investigate the effect of phosphate supplementation on resting metabolic rate (RMR) in overweight women undergoing a low-energy diet.
• To assess the impact of phosphate supplementation on thyroid hormone levels during a slimming program.
• To determine if phosphate supplementation influences other metabolic markers like plasma lipids and glucose.

Main Methods:

• A randomized, double-blind, cross-over study involving 30 overweight women.
• Participants followed an 8-week low-energy diet supplemented with viscous fibers and mineral tablets (phosphates) or placebo.
• Resting metabolic rate (RMR) and plasma thyroid hormone levels were measured.

Main Results:

• Phosphate supplementation significantly increased RMR by approximately 12-19% (p < 0.05).
• Phosphate supplementation mitigated the decrease in plasma triiodothyronine and the thyroxine to triiodothyronine ratio.
• No significant changes were observed in plasma insulin, catecholamine, growth hormone, cortisol, testosterone, lipids, or glucose levels.

Conclusions:

• Phosphate supplementation enhances RMR in overweight individuals on a low-energy diet, independent of weight loss rate.
• The observed increase in RMR appears to be partly mediated by the influence of phosphates on peripheral thyroid hormone metabolism.
• Phosphate supplementation may be a beneficial adjunct to low-energy diets for weight management in obese individuals.