If an individual with a normal ghrelin response first gains and then loses a significant amount of weight, what will happen to their fasting level of circulating ghrelin?

• A. Increase as the individual gained weight, then decrease as they lost weight
• B. Decrease as the individual gained weight, then increase as they lost weight
• C. Increase as the individual gained weight and remain high
• D. Decrease as the individual gained weight and remain low

Answer: (B)

The correct answer indicates that as the individual gained weight, their fasting level of circulating ghrelin would decrease, and then as they lost weight, it would increase.

Ghrelin, often referred to as the "hunger hormone," is produced mainly in the stomach and plays a significant role in regulating appetite. Under normal physiological conditions, ghrelin levels increase before meals and decrease after eating, reflecting hunger and satiety signals.

When an individual gains weight, particularly if they move into an overweight or obese state, the body's response is often to reduce ghrelin levels. This decrease serves a protective function against overeating and helps to regulate body weight. This means that during weight gain, the fasting levels of ghrelin would typically decrease as the body adapts to the increased energy storage.

Conversely, when the individual loses weight, especially after a significant weight loss, the body's mechanisms can promote an increase in circulating ghrelin levels. This increase is part of a physiological response aimed at stimulating appetite and encouraging food intake, as the body seeks to restore its energy balance.

In summary, during weight gain, a decrease in ghrelin levels is expected, followed by an increase in ghrelin levels during weight loss, reflecting the body's