A cafeteria diet modifies the response to chronic variable stress in rats

Area of Science:

• Neuroscience
• Endocrinology
• Nutritional Science

Background:

• Stress significantly impacts metabolic and behavioral patterns.
• Dietary intake is a key factor influencing physiological responses to stress.

Purpose of the Study:

• To investigate the interplay between chronic stress and different dietary patterns on metabolic markers.
• To examine how a highly palatable diet affects the physiological response to chronic variable stress (CVS).

Main Methods:

• Male Sprague-Dawley rats were assigned to high carbohydrate (HC), high fat (HF), or Cafeteria (CAF) diets for 6 weeks.
• Half of each dietary group underwent daily chronic variable stress (CVS) for the latter 3 weeks.
• Analysis included adiposity, serum lipids (total cholesterol, LDL, HDL), and corticosterone levels.

Main Results:

• Both chronic stress and the CAF diet elevated total cholesterol and LDL, while lowering HDL.
• The CAF diet led to increased body weight, food intake, and intra-abdominal fat.
• A significant interaction showed stress increased corticosterone in HC and HF groups, but not in the CAF group.

Conclusions:

• A highly palatable diet may attenuate the physiological stress response.
• This suggests a potential "comfort food" mechanism where palatable foods reduce the impact of stress.
• Such dietary choices could contribute to increased body weight and adiposity under stress.