Toronto: New research suggests that calorie- and nutrient-restricted diets may be linked to increased depressive symptoms, especially among overweight individuals. The findings, published June 3 in BMJ Nutrition, Prevention & Health, are based on data from over 28,000 U.S. adults collected through the National Health and Nutrition Examination Survey (2007–2018).
Led by Dr. Gabriella Menniti of Unity Health Toronto, the study found that participants on calorie-restrictive diets showed a 0.29-point increase in PHQ-9 depression severity scores compared to those not on a diet.
For overweight individuals, calorie-restricted and nutrient-restricted diets were linked to even higher score increases—0.46 and 0.61 points, respectively. The study also revealed sex-specific patterns: men following any diet experienced higher somatic symptoms, while those on nutrient-restricted diets had a 0.40-point rise in cognitive-affective symptoms compared to women not dieting.
These results diverge from earlier controlled studies that suggested dieting could improve mood. The authors noted that real-world dieting may involve nutritional deficiencies, potentially worsening mental health. They recommend that future studies focus on realistic dieting scenarios to understand their psychological impacts better.
