
Leptin When Fasting Leptin When Fasting. During a fast, the level of leptin in the blood decreases. In a study that measured the levels of leptin in the blood after a four-day energy deficit, researchers found that it fell by 39.4% and 34.9%, respectively. Leptin concentrations were 0.42 and 0.38, respectively. Increased levels of leptin…
Read More →