Plateaus
1. RESEARCH UPDATE: The Weight Loss Plateau
------------------------------------------- "The untold story about leptin and weight loss..." Have you ever found yourself stuck at a certain weight? And no matter how hard you try, you can't seem to shift those last 10 pounds of fat? Your body has a set point — a level of fat that it wants to maintain. When you try to reduce your body fat below this set point, your body fights back by reducing the number of calories your body burns each day (your metabolic rate) and turning on the appetite "switch" in your brain. The result is that weight loss slows down and you get very hungry! One of the hormones responsible for the increase in hunger is known as leptin. Leptin (the Greek term for thin) is a hormone released by your fat cells. When you lose fat, leptin levels drop. When you gain weight, leptin levels rise. When most people hear the word "hormone", they think of the sex hormones, such as testosterone or estrogen. Yet testosterone and estrogen are just two of many hormones that regulate virtually everything your body does. Your body has billions of tiny fat cells. These fat cells respond to hormones in one of two ways, depending on whether the signal is lipogenic or lipolytic. The term lipo means "fat", lytic means "breakdown", while genesis means "creation". A lipolytic (pronounced lip-o-lit-ik) hormone increases the number of fat calories burned for energy. This leads to a reduction in the size of your fat cells. Hormones that promote fat storage, on the other hand, are known as lipogenic (pronounced lie-po-jen-ik). Lipogenic hormones increase the size of your fat cells. The thyroid hormones are among the most important lipolytic hormones. However, one of the hormones in the thyroid family — known as triiodothyronine (pronounced try-o-die-thigh-ron-een) — can drop when you lose just 10% of your bodyweight. Contrary to popular belief, triiodothyronine (also known as T3) levels also drop when you include exercise as part of your weight loss program. They don't, however, drop to the same extent in everyone. Researchers from the University of North Carolina, for example, report that free T3 levels either drop or show no change in response to the same exercise program. The results reveal two distinct categories of responses — responders and non-responders. In the responders, T3 levels dropped by almost 30% after ten weeks. The non-responders, on the other hand, displayed no significant hormone changes. More interesting still, recent studies suggest that the same "master" hormone that controls the production of T3 is also linked to leptin levels. Before the discovery of leptin, body fat was seen as a lifeless source of energy. However, exciting work by researchers at the Rockefeller University in the 1990's led to a radical change in perspective. Some mice have a genetic defect that predisposes them to gain weight. When the mice were injected with leptin — the hormone this "broken" gene normally produces — the mice lost weight. Further animal research shows that leptin can prevent weight loss slowing down. Obese rats were given a mixture of the weight-loss drug sibutramine (known commercially as Meridia) and leptin, to see if the two substances together might help the overweight animals lose weight. The rats taking sibutramine alone lost more weight than rats given either leptin or saline. However, the rats given a mixture of sibutramine and leptin shed significantly more weight than the group given sibutramine alone. One of the ways in which leptin regulates weight is to increase your appetite as your body fat levels drop. Some direct evidence linking leptin and hunger in humans comes from a trial carried in the American Journal of Clinical Nutrition. Twelve overweight but otherwise healthy women followed a low-calorie diet for three months. The researchers found that the desire to eat doubled in response to the diet. More interesting still, the volunteers reporting the greatest increase in hunger were those with the largest drop in leptin. Once leptin has been secreted by your fat cells, it travels to the hypothalamus. This is the part of your brain that controls eating behavior. In the medial hypothalamus, leptin activates anorectic nerve cells, which suppress your appetite. At the same time, leptin prevents orexigenic cells from stimulating your appetite. Although it might seem counterintuitive, many obese individuals actually have high levels of leptin. On the face of it, this appears to blow all of the theories regarding leptin and weight loss out of the water. After all, if people who are obese have high levels of leptin, surely they wouldn't be obese in the first place. While obese people do have high levels of leptin circulating in their body, that doesn't mean the leptin is active where it needs to be — the hypothalamus. Instead, they seem to have developed a form of leptin resistance, where leptin is unable to make the "jump" from the blood to the brain. --- The bottom line --- As you get closer to your target weight, your rate of weight loss will slow down. It's normal, and it happens to almost everyone. However, the degree to which it happens will vary from person to person. No study has shown that if you deprive people of the same number of calories, they will all lose the same amount of weight. The effect of leptin on hunger and weight loss is still controversial. There is evidence to show that daily leptin injections help some people to lose weight faster, while a low-dose course of "replacement" leptin may reverse some of the metabolic changes that occur during weight loss. As with many drugs, the long-term effects are not well understood, and there are still more questions about leptin than there are answers. For many people, losing fat and keeping it off is difficult. Yet, there are no quick fixes or easy solutions. The concept of reward without work simply does not exist anywhere in Nature. A farmer, for example, must work hard — preparing the ground and planting the seed — before expecting to get a great harvest. Don't be deceived by the false promises of "negative calorie diets" that claim to help you lose up to 14 pounds of weight in seven days. Almost anything difficult, any challenge, takes patience, time and a desire to work for it with all your heart. To view this update on-line, visit: http://thefactsaboutfitness.com/research/leptin.htm |
This was very interesting
I do have a question though. So is this article saying we get more hungry as we lose weight? Is this a normal or abnormal reaction?
Also if you have alot to lose, is resistence a normal thing and does it every go away? |
As leptin gets lower your appetite increases, your metabolism slows down, and your body burns more muscle. Your body works against losing weight believing you are starving. In a modern traditional, low-calorie, hi-carb diet, leptin levels drop right away causing a stop in weight loss and tremendous food cravings.
It is not clear to me what low-carbing does. Leptin must go down but the food cravings must have something to do with carbs. Eating more protein likely helps save your muscles. There is a good chance it has something to do with plateaus. The article failed to say that leptin can be regenerated by eating carbs, commonly known as a refeed. A day of Coke and fruit loops will raise you leptin levels nicely, and add a couple pounds. The thinner you get the more you need leptin (and refeeds) in order to loose weight. Body builders seem to know about Leptin. http://www.theministryoffitness.com...s/article18.htm I have believed in the leptin concept for a while, having learned about here. I am now getting thin enough that I refeed every week. I have managed maintain a .5 to 1 pound weight loss every week since starting refeeds. I consider refeeds a weight loss tool to accompany this amazing low-carb diet. When I get to my target weight, I hope that it will be the end of refeeding, and then onto low-carb maintenance. |
While it may work for some, I question recommending a "refeed" as a general policy. For one, those carbs can trigger a totally falling off the wagon for the addicted. I have been low carbing for 9+ months and have had 2 plateaus after the induction one. The weight loss always starts up again and i don't have any different hunger pattern that I did when I started. I have also read a number of stories of people who did strict Atkins and lost 100+ without going off plan.
I found the article interesting and informative, but Ithink that the evidence shows that low carb is a bit different. The leptin seems to be regenerated during plateaus even if you stay with low carb. Nyah Levi |
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