All of you have had it before. The "munchies," and you just can't seem to put the food away. You aren't hungry, but you still have to have that piece of cake or that chocolate bar that you've been so diligent on not devouring like you haven't eaten in 3 months. But actually, these feelings are an integral part of the homeostatic portion of our brain, related to making sure we have enough energy for survival.
For a while now, it has been known we have two categories related to our eating behaviors. One is the homeostatic portion, and the other is the hedonic, or reward related portion of our brain. Scientists used to think they were two distinct categories, but now they realized they are quite intertwined with one another. Hormones that contribute to the homeostatic portion and controls appetite are insulin and ghrelin, associated with the feelings of being full, and leptin, associated with the feelings of hunger. These hormones converge in the same area of the brain, the mesolimbic dopamine system, associated with reward and pleasure.
Although you may be wondering why we would adapt to have appetite and pleasure on the same neurological pathway, but it is actually beneficial for survival. If something isn't rewarding, our brains won't tell us to do it, and we won't, thereby starving ourselves. So, many of these appetite hormones have been wired on the same pathway as reward and pleasure, such as ghrelin, which is a contributing hormone to make the switch from simply eating to fulfill our hunger pains, to binge-eating everything you see in your house.
This makes targeting hormones for appetite suppression very difficult because they are so intertwined. Targeting dopamine targets our reward center, and not only makes us unmotivated to eat, but unmotivated to do everything else as well, possibly even causing depression. But one drug that stimulates glucagon-like peptide-1, responsible for preventing subjects from eating high fat foods, is a drug that has been used for treatment of type 2 diabetes. Targeting this hormone doesn't have as many side effects because it is secreted from such a small group of neurons in the brain.
We can also prevent binge eating by promoting lifestyle changes such as implementing exercise. A study in Texas showed that exercise interventions caused a decrease in binge eating individuals. So next time you want that piece of cake, take all that desire out on a run. You won't want that sugary goodness by the time you finish.
Sources:
https://www.sciencenews.org/blog/scicurious/need-feed-and-eating-pleasure-are-inextricably-linked
Mama, S., Schembre, S., O'Connor, D., Kaplan, C., Bode, S., & Lee, R. (2015). Effectiveness of lifestyle interventions to reduce binge eating symptoms in African American and Hispanic women. Appetite, 95(1), 269-274. doi:10.1016/j.appet.2015.07.015
First of all, I will not put down my muffin!! However, I did read this post and it stirred up some reminiscent memories of my undergraduate sleep physiology course. So I did a little digging into my old textbook to find out what distant though was rattling around in my head...
ReplyDeleteTurns out the hormones you discussed above, leptin and ghrelin, are influenced by sleep. I don't intend to discuss pages and pages of text, but I will present a few interesting take-a-ways from my reading.
-Sleep restriction (i.e. only allowing a subject to have a partial night sleep) influences leptin's capacity to correctly signal caloric need and as a result, produces an internal misperception of insufficient energy intake. This confusion may increase intake when muffins, or any food for that matter, is available.
-When subjects are limited from ten hour sleep times to four hour sleep times for two consecutive days leptin levels were 19% lower and ghrelin levels were 24% higher than normal daytime levels. This increase in the baseline ghrelin to leptin ratio is highly correlated with increased hunger.
Based on further exploration of this topic leptin and ghrelin can be largely influenced by sleep. The information I collected was from my Basics of Sleep Guide: Second Edition by the Sleep Research Society. Throughout that course, sleep, an abstract phenomena, plays an essential role in proper homeostatic control and maintenance of the human body.
This is so interesting and makes so much sense! Since eating is crucial for survival, it makes complete sense that the pathways would evolve together to promote the act of eating by stimulating a brain region that also controls feelings of pleasure. It also makes sense, then, that people who are sad/depressed/emotionally unbalanced often turn to food to make them happier. It's an easy way to stimulate the happy centers of the brain, and who doesn't like eating? I think that the trick, in that case, to get people to stop binging on food when they're sad (and not hungry) is to emphasize other, healthier ways that they can increase feelings of happiness, such as yoga, meditation, exercise, music, etc. Personally, I am a huge fan of yoga for meditation and exercise purposes, and feel that I'm happier after a yoga session and don't need to eat as much to get that good feeling. Studies on the effect of yoga on eating disorders have been positive, but more research should be done into the relationship before any conclusions are drawn (Neumark-Sztainer, 2013). I wrote a blog on neuroplasticity and how you can control the way your brain works, in that you can implement desired thought processes by changing your mental attitude. The hormones are clearly going to play a role, but there are other ways that you can re-route your brain to avoid eating that muffin.
ReplyDeleteReference: Neumark-Sztainer, Dianne. "Yoga and Eating Disorders: Is There a Place for Yoga in the Prevention and Treatment of Eating Disorders and Disordered Eating Behaviours?" Advances in Eating Disorders 2.2 (2013): 136-45. Web.
Proto-col Slim-Fizz is a distinctive appetite suppressant that contains the ground-breaking fibre Glucomannan, which is a natural dissolvable fibre extracted from high quality fresh Konjac.
ReplyDelete