From the Guidelines
Yes, a high-fat diet can increase cortisol levels.
Rationale
- The relationship between cortisol and metabolic syndrome (MetS) is well established, with hypercortisolemia leading to visceral obesity and increased cardiovascular mortality 1.
- Elevated cortisol levels are associated with abdominal fat distribution, insulin resistance, and type 2 diabetes mellitus (T2DM) 1.
- Animal models have demonstrated the role of cortisol in mediating visceral fat accumulation, insulin resistance, and T2DM 1.
- While the study does not directly investigate the effect of a high-fat diet on cortisol levels, it highlights the link between cortisol, visceral obesity, and MetS, suggesting that a high-fat diet may contribute to increased cortisol levels 1.
- The evidence suggests that cortisol plays a crucial role in the development of MetS, and a high-fat diet may exacerbate this process by promoting visceral fat accumulation and insulin resistance.
From the Research
Cortisol Levels and High-Fat Diet
- The relationship between a high-fat diet and cortisol levels is complex and has been studied in various contexts.
- A study from 1981 2 found that dietary protein plays an important role in meal-stimulated cortisol release, but did not specifically examine the effects of a high-fat diet on cortisol levels.
- A 2022 systematic review and meta-analysis 3 found that low-carbohydrate diets, which are often high in fat, may increase resting cortisol levels in the short term, but have no consistent effect on resting cortisol in the long term.
- Another study from 2019 4 found that high-fat diet in mice led to arrhythmic daily fluctuations in corticosterone levels, and exaggerated stress responses in the early active period.
Comparison with Other Diets
- A 2022 systematic review and meta-analysis 3 compared the effects of low-carbohydrate diets with high-carbohydrate diets on cortisol and testosterone levels in men, and found that low-carbohydrate diets increased resting cortisol levels in the short term.
- A 2023 study 5 found that real-world dietary intake of sugars, but not saturated fat, was associated with reduced cortisol reactivity following an acute physiological stressor.
- A 2016 systematic review and meta-analysis 6 found that fasting, but not less severe calorie restriction, was associated with acutely elevated plasma cortisol levels.
Mechanisms and Context
- The mechanisms by which a high-fat diet may affect cortisol levels are not fully understood, but may involve changes in glucose and insulin regulation, as well as alterations in the hypothalamic-pituitary-adrenal axis.
- The context in which a high-fat diet is consumed, including the presence of other dietary components and the overall energy balance, may also influence its effects on cortisol levels.
- Further research is needed to fully understand the relationship between a high-fat diet and cortisol levels, and to determine the potential implications for human health.