Weight loss strategies, stress, and cognitive function: supervised versus unsupervised dieting.

Area of Science:

• Neuroscience
• Psychology
• Endocrinology

Background:

• Dieting for weight loss is linked to neuro-psychological impairments.
• The role of dieting support in these impairments is unclear.
• Elevated corticosteroid levels are a potential cause.

Purpose of the Study:

• To investigate the effects of supported versus unsupported dieting on cognitive function.
• To examine the role of cortisol levels in these effects.
• To compare cognitive performance and physiological changes in different dieting conditions.

Main Methods:

• Healthy, overweight, pre-menopausal women were randomized into supported dieting, unsupported dieting, or control groups for 8 weeks.
• Cognitive tests (reaction time, vigilance, memory, executive function) and salivary cortisol levels were measured at baseline and multiple time points.
• Body weight, body fat percentage, and food intake were also monitored.

Main Results:

• Unsupported dieters showed significantly poorer vigilance and executive planning after 1 week.
• Unsupported dieters exhibited a significant rise in salivary cortisol levels.
• Both dieting groups achieved similar weight loss, but only unsupported dieters showed a significant decrease in body fat percentage.

Conclusions:

• Unsupported dieting, unlike supported dieting, is associated with short-term neuro-psychological impairments.
• Increased cortisol levels may mediate the cognitive effects of unsupported dieting.
• Further research is needed to clarify the causal relationship between stress, cortisol, unsupported dieting, and cognitive function.