Which hormone, associated with fat storage, has an appetite-suppressing effect?

Leptin is the hormone that is primarily involved in regulating energy balance by inhibiting hunger. It is produced by adipose (fat) tissue and plays a vital role in the long-term regulation of body weight. Higher levels of leptin are typically associated with increased fat storage, and this hormone signals to the brain that the body has enough energy stored, thus suppressing appetite.

When fat stores increase, leptin levels rise, leading to a decrease in appetite, thereby helping to maintain energy homeostasis. In contrast, lower levels of leptin can stimulate appetite, as seen in situations of calorie restriction or weight loss, where fat tissue decreases and consequently reduces leptin production.

In contrast, insulin is primarily involved in glucose metabolism and does influence hunger to some extent, but its role is not as directly related to fat storage and appetite suppression as that of leptin. Ghrelin is known as the "hunger hormone," as it stimulates appetite rather than suppressing it. Adrenaline, or epinephrine, is involved in the body's fight-or-flight response and can affect energy mobilization rather than directly regulating appetite. Therefore, leptin is the key hormone in this context for suppressing appetite while being associated with fat storage.