Ghrelin is a potent appetite stimulant that is released from the stomach. This hormone makes foods high in fat and calories especially appealing. Every wonder why you eat more if you’ve skipped a meal or have not been getting enough sleep lately? Ghrelin is the culprit! Not only does ghrelin urge you to order that late night pizza before a big exam, but a recent study by Dr. Jeffrey Zigman shows that it could also play a role in stress eating. When you’re stressed, there is nothing more comforting than mashed potatoes, ice cream and macaroni and cheese right? No wonder I gain those few extra pounds during finals! Thanks ghrelin.
Interestingly, high levels of ghrelin can reduce anxiety and depression – before it makes you want to stuff your face. Dr. Zigman proposed that this may have been an evolutionarily advantageous response. In order to catch a high-calorie dinner, our ancestors had to be calm and vigilant, as opposed to depressed and anxious. Perhaps this was also beneficial in the past so that humans had the glucose they needed to maintain high energy levels while fighting animals or enemies. Either way, I think we can agree that in most of our lives today, the effects of ghrelin are more of a disadvantage, often resulting in weight gain. We live in a stressful world. Perhaps ghrelin plays a role in higher obesity rates, as more people experience chronic stress.
Dr. Zigman’s study examined rats that underwent chronic social stress. I am curious if these high ghrelin rates also occur during acute stress. This may seem counter intuitive as the sympathetic nervous system and glucocorticoids inhibit digestion during periods of acute stress, but our feeding mechanism is pretty complicated. As for treating obesity, unfortunately ghrelin is not the answer. Ghrelin levels are remarkably low in obese individuals. Perhaps stress causes high ghrelin levels, which causes overeating and weight gain, which eventually results in hypersensitivity to ghrelin. More research must be done to find out!
Check out the article!! http://www.sciencedaily.com/releases/2011/06/110623130336.htm