What makes sense for one should make sense for another. While that may not be correct for all humans, it's true for many hormones - and especially the role they play in whether you lose or gain weight.

With that said, let's review the role that the best known weight-affecting hormone, insulin, plays in the process.You eat. The food gets digested. The protein and carbs get sent to the liver, causing the liver to stop releasing previously digested carbs as fuel as it transforms most of the newly consumed carbs into glucose, which then gets sent into the blood stream.Blood sugar levels rise In response, the pancreas releases insulin.Insulin then escorts glucose and the amino acids (broken-down protein) not needed by the liver to the cells of muscle tissue. It's a well-mannered escort, "opening the cellular door" for the nutrients when they get there. This last point is significant because glucose and amino acids alone can't open the door, meaning you'd get really weak and then really dead without your body secreting insulin.Typically, muscle tissue holds between 1000 and 1600 calories of stored carbs (enough to sustain about two hours of running at marathon-distance pace), which means that many recreational exercisers really never run out during their workouts. And in any case, if your carb consumption exceeds the need for replacement energy before or after exercise, insulin takes the glucose back into the blood stream and converts it into the fatty acid triglyceride (though this is far less likely to happen immediately after intense exercise). The 90 percent or more that doesn't get wasted in the conversion now gets escorted by insulin to the fat stores.While it's always good to review the most likely way you add body fat, the explanation also establishes something else: when it comes to losing or gaining weight, what's secreted by your body is as important as what's consumed by it.Research has shown that eating, sleeping (or not sleeping), exercising, and reacting to stress causes other hormones to secrete. Couldn't those secretions be as important as insulin for adding - or not adding - body fat?Probably yes.What keeps the "probably" from being a "definitely" is that there are about 50 hormones, and researchers they haven't quite figured out how they interact.In an article for Precision nutrition.com titled "Leptin, ghrehlin, and weight loss," Helen Kollias jokes those interactions and how they affect body weight seem "to be only slightly more complicated than a nuclear reactor and brain surgery combined."That's because "no single hormone controls body composition, appetite, and hunger - and your individual hormonal profile may be relatively unique."As a result, the goal of this column is not mastery of the subject matter, but heightened awareness.Body fat, surprisingly enough, secretes hormones depending upon what a November 2015 Environmental Nutrition article calls "cross talk" - signals going back and forth from other parts of the body, including the brain, gut, adrenals, and pancreas. Leptin, the hormone that signals food consumption can stop, actually comes from body fat.If the fat stores signaling enough is enough strikes you as odd, so will the fact that fat people secrete more leptin than those who maintain a healthy weight, particularly those who work out.This makes Kollias's prior quip especially appropriate, as well as the review of insulin. For in the same way a bad eater can create insulin resistance by constantly ingesting the bad carbs that skyrocket blood sugar, the overweight person who produces leptin constantly ultimately becomes unaffected by it.Leptin resistance and its tendency to make you overeat plays a significant role in why the diet I prescribe to those desiring optimal athletic performance or low body fat does not include fruit. Studies have shown that fructose, the primary sugar in most fruits, makes it easier to develop leptin resistance.Another hormone secreted by fat, adiponectin, battles a far better known resistance, insulin resistance, primarily by moderating blood sugar levels, but a hormone produced by the adrenal glands, cortisol, produces the opposite, an excess of sugar in your bloodstream. It does so by signaling the fat stores to release energy and begin protein breakdown.This secretion is essential for fight-or-flight situations when extraordinary physical effort could be required, such as when you believe there's a burglar in the house or you need to break parallel in that last rep in a heavy set of squats.You also produce cortisol as a result of mental stress, and every time this happens, unfortunately, it breaks down muscle mass.Less muscle mass means you'll need fewer calories to maintain your present weight. Cortisol secretion also increases the odds you'll get sick, since it suppresses the immune system.While this discussion on hormones is far from inclusive, it stresses one idea that has been central to this column since its inception: synergism, the idea that many systems in the body need to work in harmony for optimal health.The many ways hormone secretion affects body weight proves that.Contact Kevin Kolodziejski by email at

kolo@ptd.net