Cutting calories too drastically may be linked to increased symptoms of depression, according to new research published in BMJ Nutrition, Prevention & Health. The study analyzed data from over 28,000 adults participating in the US National Health and Nutrition Examination Survey (NHANES), assessing their diet quality and depressive symptoms.
Researchers found that individuals following calorie-restrictive diets—especially men and those classified as overweight—were more likely to report higher levels of depression.
The quality of the diet also played a significant role: diets high in ultraprocessed foods, refined carbohydrates, saturated fats, processed meats, and sweets correlated with greater depressive symptoms, whereas adherence to a Mediterranean-style diet was associated with a lower risk of depression.
Dr. Venkat Bhat, lead author and psychiatrist at St. Michael’s Hospital and the University of Toronto, cautioned against overly restrictive or unbalanced diets, particularly for people already facing weight-related stress.
He recommends balanced, sustainable dietary changes that meet nutritional needs while considering psychological impacts to minimize negative mood effects.
The study’s observational design means it can only show associations, not causation. Self-reported dietary data may also introduce inaccuracies, as participants might misjudge their calorie intake.
For example, a person may believe they are restricting calories when they are actually consuming a surplus. This contrasts with previous research where medically supervised calorie restriction often led to reduced depressive symptoms, suggesting that unsupervised dieting might cause nutritional deficiencies that worsen mood.
Experts highlight several reasons why calorie restriction might negatively affect mental health. Without adequate nutrients, physical processes can be disrupted, leading to fatigue, sleep disturbances, and concentration difficulties.
Additionally, unsuccessful dieting or weight cycling can cause frustration and exacerbate depression. Extreme dieting behaviors are also linked to increased anxiety and heightened risk of eating disorders.
Nutrition professionals recommend focusing on balanced eating patterns rather than severe calorie cuts. Dietitian Natalie Mokari advises starting with small, manageable changes to meals, ensuring plates include protein, carbohydrates, healthy fats, and fiber-rich fruits and vegetables.
Prioritizing nutritional quality can improve overall health and mood, regardless of weight loss goals. Consulting a registered dietitian or medical professional before beginning any weight loss regimen is strongly advised.
In summary, while calorie restriction is often pursued for weight management, this study underscores the importance of a balanced, nutrient-rich diet to support both physical and mental well-being. Personalized dietary approaches that consider psychological effects are essential for sustainable health improvements.
