Changes in vitamin status in plasma during dieting and exercise

Area of Science:

• Nutrition Science
• Exercise Physiology
• Obesity Research

Background:

• Obesity is a significant health concern linked to various metabolic disturbances.
• Micronutrient status can be affected by weight loss interventions.
• Understanding the impact of diet and exercise on micronutrients is crucial for managing obesity.

Purpose of the Study:

• To evaluate the effect of a low-energy diet with or without exercise on micronutrient status in obese males.
• To compare changes in blood plasma micronutrients between a diet-only group and a diet-exercise group.

Main Methods:

• 12 obese males were divided into two groups: diet (D) and diet-exercise (DE).
• Intervention lasted 14 weeks, involving a low-energy diet (3.0-3.9 MJ) and for DE, an additional 5 hours of exercise per week.
• Micronutrient status was assessed before and after the intervention, with body mass index (BMI) used for matching.

Main Results:

• Both groups achieved comparable weight loss (approx. 15-16 kg), fat loss (approx. 11-13 kg), and fat-free mass loss (approx. 2.8-3.4 kg).
• A significantly greater decrease in blood plasma ferritin was observed in the diet-exercise group (P < 0.05).
• Both groups showed significant decreases (approx. 20%) in fat-soluble vitamins, while water-soluble vitamins varied with no significant overall decrease.

Conclusions:

• Combining a low-energy diet with exercise may lead to a more pronounced reduction in ferritin levels in obese males.
• Weight loss through diet and exercise significantly impacts fat-soluble vitamin levels.
• Further research is needed to understand the variability in water-soluble vitamin responses.