The effects of carbohydrate-restricted diet on psychological outcomes: a systematic review of randomized controlled trials.

This article systematically reviews randomized controlled trials (RCTs) examining the effects of very low-carbohydrate high-fat (VLCHF) and ketogenic diets (KD) on psychological outcomes, including quality of life (QoL), mental health, mood, and fatigue, in adult populations. Sixteen RCTs involving clinical, obese/overweight, and healthy adults were analyzed, revealing that VLCHF or KD interventions generally do not negatively impact psychological well-being compared to control diets; some long-term interventions (≥12 weeks) showed improvements in QoL and mental health. The review found inconsistent results in obese/overweight populations and identified a lack of studies assessing the combined effects of these diets with physical activity or social factors on psychological outcomes. The authors highlight a research gap regarding the role of social support in sustaining these diets and recommend further high-quality studies to explore potential synergistic effects for long-term adherence and psychological benefits.