The problem with sliding down the slippery slope of slow and progressive weight gain over the years is that you may have a lot of trouble pulling yourself up and out of the hole. In fact, new science says you most likely caused brain damage by eating too much food. Such damage causes you to crave and eat what you know you shouldn’t. A variety of new studies shed light on the complex and fascinating subject of food cravings and your mind.
Around your body, insulin acts as a taxicab to transport sugar passengers to places that need them. A primary use of sugar is for fuel, like gas in your car. Since your cells don’t go to a gas station, insulin takes the gas to them. What your cells don’t need, is transported by insulin to your liver and converted to a form of short-term fuel storage called glycogen. Glycogen can readily be converted back to glucose to sustain your blood sugar levels between meals and while you sleep. If you have more sugar than your liver needs, it is transported to your white adipose tissue to be stored as fat. If that system gets overloaded, fat builds up in all the wrong places such as your liver, pancreas, heart, arteries, and muscles – causing disease.
When you eat too much food and gain weight, you develop a problem called insulin resistance. Since cells already have plenty of fuel, their membranes take down their receptors for insulin so that more fuel is not crammed into them – causing death from too much food. Likewise, your liver takes down its insulin receptors, as no more fuel is needed. Once your liver does this you are on a fast track to a fatty liver and type 2 diabetes. Insulin resistance generally means too much sugar and high levels of insulin, and no place that wants either. It is the opposite of a fuel shortage. Only humans would try to keep cramming fuel into their tank when it is already full.
The above issues are going on around your body, but it is up to your brain to figure out what to do about this sad state of affairs. Your brain actually has plenty of training to deal with this issue; unfortunately for you, it is completely irrelevant. Your brain’s prior genetic training over many generations has to do with survival in the face of starvation. You do not have long-term genetic experience to deal with over-consumption of food.
New science is now demonstrating how insulin works in your brain. This new science is based on animal studies that would be impossible to conduct in humans. It shows that there are insulin receptors in the hypothalamus gland of your brain, in the same area where leptin receptors enable a full signal following a meal. Under conditions of normal body weight, which typically means normal food availability, insulin behaves in tandem with leptin to keep metabolism running along at an optimal pace. However, under conditions of starvation, when leptin levels drop, then insulin behaves differently. It directly slows down metabolism1 while turning on food cravings. This is a survival mechanism to recover from starvation. It turns out that a high insulin surge entering your brain in conjunction with low leptin helps your body eat more food quickly and store it as fat, so as to recover from starvation. As you develop more fat, then leptin levels rise, and leptin and insulin work in tandem to facilitate faster metabolism.
That is a wonderful mechanism for starvation recovery, but it is a brutal mechanism to overcome if you have been eating too much food year after year. Unfortunately, overweight people have leptin resistance which means that leptin is high in their blood but not getting into their brain. This is a false state of perceived starvation. It makes you eat large meals that cause dramatic surges of insulin into your brain. In fact, you can tell this is happening to you any time you eat too much and feel tired instead of energized – a common complaint in overweight people following a meal (and a warning to normal-weight people not to do that too often).
This means that insulin in your brain is acting in a way that promotes weight gain, even though you are already overweight, based on the misguided use of starvation-recovery genetic programming. Unfortunately, this situation gets even worse.
Other researchers now report that as excess food is consumed, the hypothalamus gland2 in the brain becomes inflamed, glial cells and microglial cells gravitate to the area (indicating injury) and that the inflammation is consistent with weight gain. This means that brain damage is occurring in the hypothalamus gland, which will knock out receptors for insulin and leptin, making regulation of food intake much more difficult. The researchers showed that metabolically activating neurons (POMC) were even knocked out. This means that if you eat too much food on a regular basis, you injure your brain in the key area that regulates food intake and metabolic activation. This is different than a nutritional deficiency; it is roads and bridges that are missing.
To add insult to injury another study shows that insulin is also active in the reward center of your brain3 – meaning the desire to eat for the sake of pleasure. This is not a bad thing until the signals go out of balance. The researchers showed that normal function of insulin in the leptin-normal brain actually enables dopamine neurons to fire faster, giving you motivation and drive. However, once you start eating too much then these dopamine neurons develop insulin resistance, resulting in a slow brain and a magnified urge to eat food whether you are full or not. Yes, this is eating for the sake of eating.
Yet another study shows, when you get stressed and your nerves get inflamed, one of the ways your body calms down is by releasing ghrelin, which is your stomach’s craving for food. We already know this calms the vagus nerve, acting as an anti-inflammatory. We also know that ghrelin communicates to the hypothalamus gland and reinforces the desire to eat based on hunger. But these researchers now show that ghrelin is linked to the dopamine-reward system4 and activation of ghrelin causes you to “pleasure eat” in response to stress, making everything I have previously mentioned in this article even worse.
This situation is not hopeless, and it is certainly worth understanding since millions of Americans suffer from these issues. To overcome these problems you need to eat in harmony with leptin, which means following the Leptin Diet. You need to consistently perform aerobic exercise, which increases leptin receptor function in your body and helps to promote improved brain plasticity to recover from this damaging state of affairs. You need to manage stress well and use enough stress-buster nutrients to help stay above the fray. And you need to use nutrition to help restore brain plasticity. This whole process may take some time, but eventually your metabolism can begin working again. Obviously, if you relapse while you are trying to get better, you will take several steps backwards.
The moral of the story is, once you get your body on track you need to keep it on track for a number of months in a row so as to repair the damage that has been done. Doing so will not only help your metabolism, it will help your motivation, stress management ability, cognitive function, and mood. There are rewards to be had if you can get yourself out of the rut of survival programming gone awry.
- ^ Insulin Helps Recovery From Starvation Nature Neuroscience Tim Klöckener, Simon Hess, Bengt F Belgardt, Lars Paeger, Linda A W Verhagen, Andreas Husch, Jong-Woo Sohn, Brigitte Hampel, Harveen Dhillon, Jeffrey M Zigman, Bradford B Lowell, Kevin W Williams, Joel K Elmquist, Tamas L Horvath, Peter Kloppenburg, Jens
- ^ Eating a High-Fat Diet May Rapidly Injure Brain Cells That Control Body Weight The Endocrine Society’s 93rd Annual Meeting in Boston. Joshua Thaler, et al.
- ^ Insulin Status in the Brain Influences Dopamine and Food Cravings Cell Metabolism A. Christine Könner, Simon Hess, Sulay Tovar, Andrea Mesaros, Carmen Sánchez-Lasheras, Nadine Evers, Linda A.W. Verhagen, Hella S. Brönneke, André Kleinridders, Brigitte Hampel, Peter Kloppenburg, Jens C. Brüning
- ^ Ghrelin, Stress Eating, and Dopamine Journal of Clinical Investigation Jen-Chieh Chuang, Mario Perello, Ichiro Sakata, Sherri Osborne-Lawrence, Joseph M. Savitt, Michael Lutter, Jeffrey M. Zigman.