A recent study has said that lifestyle-induced weight loss increases the fasting levels of ghrelin, the hunger hormone, which may help to reduce visceral fat and improve insulin sensitivity.^1.2

In this study, the levels of fasting ghrelin were measured in 294 participants over a period of 18 months. Also, in a secondary analysis, persons with either abdominal obesity or dyslipidemia were randomized to one of three diets: healthy-dietary-guidelines, Mediterranean diet or green- Mediterranean diet. The green-Mediterranean diet included daily intake of 3-4 cups of green tea plus Mankai (a green leafy vegetable rich in fiber and polyphenols) shake and excluded red meat. Otherwise, both the Mediterranean diets were similarly hypocaloric. Each study participant was also advised physical activity in addition to the specific diet pattern. Estimation of body fat was done with the help of an MRI done at baseline and at the end of the study period.

Results published in the Journal of Clinical Endocrinology & Metabolism show that at 18 months, despite similar caloric restriction and weight loss, the levels of fasting ghrelin showed a two-fold increase in participants in the green-Med group compared to those in the traditional Mediterranean diet group and the healthy balanced diet group; 10.5% vs 5.4% vs 1.3%, respectively. Lower fasting ghrelin levels were associated with higher visceral-adipose-tissue (VAT), intra-hepatic fat, leptin and blood pressure, all indicators of adverse cardiometabolic status. An inverse association was seen for fasting ghrelin levels and insulin resistance and VAT.

This study has shown that a healthy eating pattern leads to an increase in fasting ghrelin levels, with the green-Mediterranean diet showing greater increase in fasting ghrelin levels compared to the traditional Mediterranean diet. Increased ghrelin levels are associated with abdominal visceral fat loss and improved insulin sensitivity, which in turn decrease the risk of developing diabetes or other metabolic diseases such as hypothyroidism, prediabetes, metabolic syndrome, NAFLD. Conversely, this also suggests that lower fasting ghrelin levels are associated with weight gain and obesity and adverse heart health.

Hence, ghrelin, which appears to play a role in “maintaining glycemic levels and metabolism”, can be considered as an indicator of cardiometabolic health following weight loss.

Reference

1. Tsaban G, et al. Diet-induced fasting ghrelin elevation reflects the recovery of insulin sensitivity and visceral adiposity regression. J Clin Endocrinol Metab. 2021 Oct 13;dgab681. doi: 10.1210/clinem/dgab681.
2. Endocrine Society Press release, October 13, 2021.