Tuesday, July 23, 2013

Leptin Hormone

Have any of you ever heard of it? I hadn't until the last time I went to the doctor. She had told me how it was a relatively new thing they are learning about. And how it usually goes hand in hand with thyroid problems, being over weight, and over eating. So she suggested I get tested to see what my level was at.
It took a lot longer to get my test back than I thought it would! And I really hadn't given the leptin thing much thought. Then I got the call yesterday about all my blood work. My thyroid was a little off like I thought, my vitaminD is still really low, still insulin resistant, and now so is my Leptin. 
Let me explain what Leptin is though. Leptin is a protein that's made in the fat cells, circulates in the bloodstream, and goes to the brain. Leptin is the way your fat cells tell your brain that your energy thermostat is set right. Leptin tells your brain that you have enough energy stored in your fat cells to engage in normal, relatively expensive metabolic processes. In other words, when leptin levels are at a certain threshold -- for each person, it's probably genetically set -- when your leptin level is above that threshold, your brain senses that you have energy sufficiency, which means you can burn energy at a normal rate, eat food at a normal amount, engage in exercise at a normal rate, and you can engage in expensive processes, like puberty and pregnancy. 
But when people diet, they eat less and their fat cells lose some fat, which then decreases the amount of leptin produced. Let's say you starve, let's say you have decreased energy intake, let's say you lose weight. Now your leptin level goes below your personal leptin threshold. When it does that, your brain senses starvation. That can occur at any leptin level, depending on what your leptin threshold is.Your brain senses that and says, ‘Hey, I don't have the energy onboard that I used to. I am now in a starvation state,'.Then several processes begin within the body to drive leptin levels back up. One includes stimulation of the vagus nerve, which runs between the brain and the abdomen. "The vagus nerve is your energy storage nerve. Now the vagus nerve is turned on, so you get hungrier. Every single thing the vagus nerve does…[is] designed to make you take up extra energy and store it in your fat. Why? To generate more leptin so that your leptin can re-establish its personal leptin threshold... It causes you to eat and it causes you to get your leptin back to where it belongs.
The problem is that overweight people have large amounts of leptin, but their brains aren't getting the important signal to stop eating. How come the brain doesn't get it? That phenomenon is called ‘leptin resistance,' Leptin resistance is similar to insulin resistance in type 2 diabetes, in which the pancreas produces large amounts of insulin, but the body doesn't respond to it properly.Leptin levels can keep going higher as people get fatter. We all have a leptin floor; the problem is, we don't have a leptin ceiling. In leptin resistance, your leptin is high, which means you're fat, but your brain can't see it. In other words, your brain is starved, while your body is obese. And that's what obesity is: it's brain starvation. Not only is leptin part of the hunger system, it's also part of the reward system. When your leptin levels are low, food is even more rewarding. When your leptin levels are high, that's supposed to extinguish the reward system so that you don't need to eat so much, and food doesn't look nearly as good. But in leptin-resistant people, the reward system doesn't cue a person to stop eating when leptin levels rise. The leptin is being made by the fat cells, the fat cells are trying to tell the brain, ‘Hey, I don't need to eat so much,' but the brain can't get the signal. You feel hungrier and the reward doesn't get extinguished. It only gets fostered, and so you eat more and you keep going and it becomes a vicious cycle. If your brain can't see the leptin signal, you're going to get obese.
Leptin appears to have many functions that scientists are still exploring. It didn't work as a weight loss agent, but there's now starting to be some other things that are really interesting about it. The hormone plays a role in heart and bone health. We know that leptin is very important in keeping the immune system happy and that chronic inflammation occurs in the face of inadequate leptin signaling, and that's part of cardiovascular disease. We also know that leptin has direct effects on bone to increase bone health and bone mineral density, so when your leptin's working right, your bones are healthier and they accrue more calcium. Scientists are also finding some associations between leptin and certain cancers. For example, some recent research suggests that leptin can promote the growth of melanoma, a type of skin cancer. It may even affect women's fertility. If the brain doesn't sense leptin, you won't be fertile. If you think back to our caveman days, when there were lots of famines, if you didn't have enough fat to survive a pregnancy, then you're better off not getting pregnant in the first place. Some people have thought that the leptin feeds back on the hypothalamus to keep the reproductive hormones working well, too.
Because leptin is a digestible protein that doesn’t enter the bloodstream, it can’t be taken in supplement form. If you were to take it as a pill, it’s just like eating chicken or beef. It’s a protein and your body would just break it up, so you wouldn’t absorb it from a pill. Rather than taking supplements that haven’t been fully proven to help, overweight people have other options to aid leptin functioning, experts say. Reduce resistance to insulin (a hormone that controls blood sugar) and to bring down high levels of triglycerides (a blood lipid). Insulin resistance generates leptin resistance. The practical advice is: Get your insulin down. How do you get insulin down? The best way is don’t let it go up. Sugar makes insulin go up. We are overdosed on sugar in this country. I think that if we got the sugar down, our insulin resistance would improve and that would help with the weight loss. Reducing high triglyceride levels helps, too. Too much triglyceride interferes with leptin’s journey from the blood to the brain via a leptin transporter that allows the hormone into the brain. When you’re insulin-resistant, you have high triglyceride [levels]. That’s one of the hallmarks. Triglyceride seems to block leptin transport into the brain. In order to make your leptin work, you have to let the signaling occur. The only way to let the signaling occur is to get your triglyceride down.
So I'm kinda feeling hopeless right now. I've been on a blood sugar medicine to help my insulin level for almost 4 months now, I've been eating better trying to exercise more and yet my level was way out of the normal range. My doctor just told me to eat healthy and in small portions and that will hopefully help, but that's what I've been doing...and it sure isn't easy when you feel hungry all the time and down right tired. I'm just hoping some way some how things will improve, I don't know how they will but at this point that's all I can do is hope.