Effect of long-term use of very low-carbohydrate Ketogenic diet on the thyroid gland and adipose tissue of adult male albino rats (biochemical and histological study).

内容摘要

Ketogenic diet (KD) therapy is a high-fat, low-carbohydrate, low-protein diet with a macronutrient ratio of 89% fat, 10% protein, and 1% carbohydrates. This causes the body's primary energy source to shift to lipids. Improved glycemic control, weight loss, and the treatment of metabolic and cardiovascular diseases are among the therapeutic advantages of this metabolic shift. Therefore, this study was designed to detect if the prolonged intake of KD has beneficial or hazardous effects on the thyroid gland and adipose tissue by using 20 adult male albino rats divided into two groups. Both groups received 30 gm of food every day for 60 days: a standard diet for the control group and KD for the ketogenic group. Blood samples were taken for measurement of lipid profile and thyroid hormones. Body weight, body mass index (BMI), and food intake with atherogenic index were also measured. Tissue samples from the thyroid gland and adipose tissue were also taken for histological analysis using Hematoxylin and Eosin (H&E), Sudan black, Masson Trichrome, PAS, and immunohistochemical staining (caspase 3 and calcitonin antibodies). The results of the present study showed that the long-term use of the KD diet produced a significantly lower body weight, BMI, and food intake, with an atherogenic serum lipid profile and increased TSH levels. Additionally, it produced histological changes in the thyroid and adipose tissues with increased caspase-3 expression and a greater number of calcitonin-positive cells. In conclusion, this study highlights the adverse effects of the KD on thyroid and adipose tissues, evidenced by reduced serum T3 and T4, elevated TSH, follicular cell disruption, and adipose tissue alterations like reduced lipid droplet size and increased vascularization. The results could be alarming for the health hazards of chronic KD consumption in humans without medical supervision.