Low carbohydrate, high fat diet increases C-reactive protein during weight loss

Area of Science:

• Nutrition Science
• Metabolic Health
• Inflammation Research

Background:

• Chronic inflammation is a risk factor for heart disease, particularly in obesity.
• Oxidative stress may play a role in obesity-related inflammation.

Purpose of the Study:

• To evaluate how different weight loss diet compositions (low-carbohydrate, high-fat vs. high-carbohydrate, low-fat) affect inflammation.
• To determine if observed changes in inflammation are related to oxidative stress.

Main Methods:

• Twenty-nine overweight women were randomized to either a low-carbohydrate (LC) or high-carbohydrate (HC) diet for 4 weeks.
• Weekly measurements included body weight, serum interleukin-6 (IL-6), C-reactive protein (CRP), urinary 8-epi-prostaglandin F2alpha (8-epi), blood glucose, and free fatty acids.

Main Results:

• Both diets had similar caloric intake, but differed in macronutrient composition.
• The low-carbohydrate diet group lost more weight, but their C-reactive protein (CRP) levels increased by 25%.
• The high-carbohydrate diet group showed a 43% reduction in CRP, and while IL-6 increased in both groups, urinary 8-epi showed no consistent pattern related to diet composition.

Conclusions:

• Diet composition significantly influences inflammation markers during weight loss.
• High-carbohydrate, low-fat diets may be more effective in reducing C-reactive protein (CRP) compared to low-carbohydrate, high-fat diets.
• The study did not find evidence linking diet-induced changes in inflammation to oxidative stress.