Calorie-Restricted Diets Linked to Increased Depression Risk, Study Finds

A recent study led by Gabriella Menniti, a researcher at the University of Toronto, has revealed alarming correlations between calorie-restricted diets and elevated levels of depression among participants. This research, published in the Journal of Nutrition and Mental Health on June 1, 2025, highlights the potential mental health risks associated with popular weight loss strategies that prioritize rapid fat loss through significant calorie reduction.

The study analyzed data from 28,525 adults participating in the U.S. National Health and Nutrition Examination Survey from 2007 to 2018. Participants were categorized into four groups: those not adhering to any specific diet, individuals on calorie-restricted diets, those on nutrient-restricted diets (such as low-fat or low-carb), and participants following established dietary patterns like the DASH (Dietary Approaches to Stop Hypertension) diet. The researchers assessed depression levels using a standardized questionnaire, identifying scores of 10 or above as indicative of serious mental health issues.

Findings indicated that individuals on calorie-restricted diets reported significantly higher depression scores compared to those not following such diets. Particularly concerning was the impact on overweight participants, whose mental health suffered more severely under these dietary restrictions. Symptoms of depression, such as fatigue, sleep disturbances, and changes in appetite, were notably prevalent among men, likely due to their higher nutritional requirements.

Dr. Menniti explained, “This discrepancy may arise because prior studies typically involved randomized controlled trials (RCTs) where participants adhered to structured diets ensuring balanced nutrient intake. In contrast, real-world calorie-restricted diets often lead to nutritional deficiencies, particularly in protein and essential vitamins and minerals, which can exacerbate depressive symptoms.”

The implications of this study are significant, especially given the increasing popularity of calorie-restricted diets in weight loss programs. Previous literature had suggested that weight loss could enhance mood; however, this new research presents a troubling counter-narrative.

Experts in the field have responded to these findings with a call for caution. Dr. Sarah Johnson, a Professor of Psychology at Harvard University, emphasized the importance of considering mental health when implementing dietary changes. “The psychological effects of dieting are often overlooked, and this study underscores the necessity for holistic approaches that prioritize both physical and mental well-being,” Dr. Johnson stated in a commentary following the publication of the study.

Moreover, Dr. Michael Adams, a nutrition specialist at the Mayo Clinic, pointed out that diets low in carbohydrates and fats could impair brain function. “Nutritional deficiencies can lead to cognitive-affective symptoms that are particularly detrimental in men, who typically have greater nutritional needs,” he explained.

As the conversation around diet and mental health continues to evolve, experts advocate for balanced dietary approaches that ensure adequate nutrition while promoting sustainable weight loss. The study's findings serve as a reminder that while achieving physical health goals is important, the psychological costs of restrictive diets must not be ignored.

In conclusion, the research highlights a critical intersection between nutrition and mental health. As individuals seek to improve their physical health through dieting, it is imperative to consider the comprehensive impact of these dietary choices on mental well-being. Future studies are needed to further explore the long-term effects of various dietary patterns on mental health, ensuring that strategies for weight loss do not come at the expense of psychological resilience.