Source / Disclosures
Cignarelli A, et al. Abstract # 743. Presented at: European Congress of Endocrinology; May 22-26, 2021 (virtual meeting).
Disclosures: Cignarelli does not report any relevant financial information.
A very low-calorie ketogenic diet promotes a dramatic and early effect on insulin resistance and testosterone levels in overweight or obese men, according to a small study presented at the European Congress of Endocrinology.
The results highlight the strong relationship between glucose regulation and liver and testicular function, Angelo Cignarelli, MD, PhD, assistant professor in the section of internal medicine, endocrinology, andrology and metabolic diseases at the University of Bari Aldo Moro, Italy, said during a virtual presentation.
“Functional hypogonadism is commonly seen in obese adults, and we know that a low-calorie ketogenic diet can quickly affect body weight,” Cignarelli told Healio. “We also know that weight loss is associated with increased testosterone levels; However, whether this recovery may be due to the weight loss itself or some other early mechanism is still a matter of debate.
Cignarelli and his colleagues analyzed data from 17 overweight or obese men without diabetes (mean age, 41 years; mean BMI, 36.4 kg / m²) on a very low-calorie ketogenic diet for 4 weeks. Participants underwent an oral glucose tolerance test, bioelectrical impedance analysis, and blood tests to assess glycemic response and levels of insulin, total testosterone, sex hormone binding globulin, and hormone. luteinizing at 1 and 4 weeks.
Within the cohort, the mean baseline total testosterone was 2.5 ng / mL and the mean baseline SHBG was 24.2 nmol / L.
After following the very low-calorie ketogenic diet, the mean weight loss for the cohort was -9.3 kg, the mean fat loss was -6.5 kg, and the mean reduction in BMI was -3 , 1 kg / m². At 1 and 4 weeks, mean total testosterone increased by 0.49 ng / mL and 0.89 ng / mL, respectively. The researchers also observed mean increases of 3.47 ng / mL and 10.94 ng / mL in serum SHBG levels at 1 and 4 weeks, respectively.
By assessing high and low diet responders, the researchers found that the high responders differed only in the level of insulin sensitivity.
“Indeed, the weak responders, despite a comparable blood sugar level during OGTT, displayed a significantly higher level of insulinemia, indicating that they were more resistant to insulin than the high responders,” wrote the researchers in an abstract.
“We found a significant increase in testosterone level at the end of the study, and almost half of this increase was seen after just 1 week of nutritional intervention alongside a dramatic reduction in insulin levels,” Cignarelli told Healio. “Therefore, the low-calorie ketogenic diet could be used safely to improve hypoandrogenemia and possibly save obese patients from functional hypogonadism.”