The best approach to understanding how the human system is intended to work is actually to look at the metabolism of a hypothetically healthy adolescent from back in the day before the era of information technology, now known as the Internet Age.
Children would come home from school and eat a healthy snack, which in turn would regulate their blood sugar levels by gradually secreting small amounts of insulin to the pancreas. The excess sugar is then escorted to the muscle cells, and the body continues to function, which later will be used as energy when the child starts playing again. Then the blood sugar level of the child will start to drop to a normal range before the child even begins to get hungry, which by this stage would already be dinnertime. However, this is no longer the case.
Looking at today's habits, the functioning of our bodies indicates that everything is upside down. We start the day late, dress in a frenzy and fuel our bodies with a cup of sweetened coffee accompanied by a sugary snack to which our blood sugar counter starts to fail from skyrocketing levels. The blood sugar increase is still equal to insulin but now with our condition it's a truckload of insulin. Insulin's task is to escort the sugar in the blood to muscle cells, but since these cells have their own limits they do not want or need any more sugar than what is necessary. They actually become rude and resist taking that sugar from the blood. According to our biochemical pathway, the insulin now has no other choice than to take its sugar load to another location. It is an adventure story that doesn't bode well as it ends up in the fat cells. Our fat cells welcome the sugar, which is often under constant attack due to our high carbohydrate diets. Eventually, our cells become resistant to our eating habits and after all this the sugar and insulin have nowhere to go and our blood levels of insulin and sugar are high. It means that you are well on the way to Type 2 diabetes.
However, the story does not end there. Insulin metabolically locks the doors of fat cells. In other words, this means that if you have high insulin levels it is almost no longer possible for your body to burn fat. This is the end result of constant bad eating habits. This is also the same exact temporary situation when we eat carbohydrate- intense foods.
Fat is stored in different forms and locations of the body. The fat you can pinch, which is below the skin, is called subcutaneous fat. Its major role is to support body parts. If you have injured or deeply cut your skin, the yellow droplets you see under the skin are called the subcutaneous fat. When compared with other fats, this fat is not that bad if it is not excessive.
The fat that you do not see is the wicked one; it's the abdominal fat, visceral fat and also the omentum. General surgeons call omentum the gold of your abdomen - gold by color not by value. It surrounds your organs and has nowhere else to go; it causes hypertension, diabetes, fatty liver, and inflammation all around your abdomen. That's why health professionals are always concerned about your waist measurement - it's the only number that gives a clue as to how big that monster inside you is.
I know that none of you would ever want a fat pillow hanging around your waist. Most of you have experienced that your belly is the place where fat builds up first and is also the last place to leave even after a challenging diet. The problem here is not only insulin, but also your hormones.
An increased waist measurement may be an indicator of one or more hormonal imbalances, including high estrogen, low testosterone, low adrenal gland hormone (DHEA), high insulin, high leptin, and high cortisol. A program to clear off this dogged abdominal fat must include appropriate diet, routine exercise, good sleep and strong motivation. All of these components will contribute to a healthy balance in your body that will allow fat loss. Let's look in detail at the hormones that are so-called major components of your fat metabolism switch.
1- Insulin
Insulin is the fundamental hormone that mainly functions to process sugar in the blood and carry it into cells to be used as energy or stored as fat. It is nothing new; it was in our blood 30 years ago and continues to be in it now, but only in higher levels. The primary cause of increased insulin levels is excessive intake of sugar (carbohydrates), typical of many diets or processed foods today.
Processed foods include sugary drinks and sodas, packaged foods, low-fat dairies. Higher insulin levels cause insulin resistance over time, as we discussed earlier. But insulin resistance can also be attributed to lack of exercise, overindulging or binge drinking of alcohol, excessive stress, genetic history of diabetes, current hypertension and, of course, excess body fat around the abdomen (think of your omentum-abdominal monster). Chronically high levels of insulin will lead to pre-diabetes, which is called metabolic syndrome (or insulin resistance), and it advances weight gain. As a cardiac surgeon, I see metabolic syndrome in more than 20 percent of my patients.
2- Ghrelin
Ghrelin is your hunger hormone. It is produced in the cells covering your stomach and communicates with your brain to signal that you are hungry. Calorie counters suffer from ghrelin surges because reducing calories through diet in turn causes an increase in ghrelin.
Even after long periods of a calorie limiting diet, research has shown that ghrelin levels stay elevated. In simple terms, it means that your body never adapts to eating less and will constantly emit "I'm hungry" signals. Scientists say this is the main reason why maintaining weight loss is often more challenging than losing it in the first place. Intense exercise and the hot pepper (capsaicin) decrease ghrelin levels, making them important components of a fat-loss program.
3- Leptin
Leptin is a hormone from the adipokine family, which is secreted exclusively from fat cells. Which fat cells? Your abdominal fat, of course! Leptin is the major component in your fat-burning switch. It interacts with your brain to suppress your appetite and burn more calories.
The fatter you are, the more leptin your fat cells will release. Then why are you not burning enough calories? Well, too much body fat equals too much leptin being released and that is equal to a condition called leptin resistance.
When this occurs, your brain becomes anesthetized to the leptin signal. To maximize leptin sensitivity, eat unprocessed foods and get enough sleep. Losing weight will also enhance leptin sensitivity and provide your body with some momentum.
4- Giucagon
Glucagon acts in direct opposition to insulin. While insulin stores carbohydrates and builds fat, glucagon is responsible for processing stored fats/sugars and releasing them for your body to generate energy. Eating a proteinrich and low-carbohydrate diet is the best way to maximize glucagon release. Anyone seen Atkins here?
5- Cortisol
Consistent elevation of cortisol levels, the stress hormone, is very harmful to your health. If you suffer from a mood disorder, you can be sure that your body is pushing up your cortisol. Not only a mood disorder, anything that causes stress will do the same. What do you experience when you are stressed out?
Does it increase your appetite and cravings? Of course it does, and in addition it causes loss in muscle mass, loss in libido, destruction in bone metabolism, contributes to depression, and causes memory loss. In other words, chronic stress turns us into grannies or grandpas. Research has shown that stress causes an increase in abdominal fat, even in fit people. But there's good news: Vitamin C is a great weapon to fight against stress; grab a kiwi every morning to feel the difference. Additionally, sleeping enough is the key factor in balancing the stress hormone.
6- Estrogen
Belly fat in men increases the conversion of testosterone into estrogen by an enzyme called aromatase. When estrogen levels rise, the tendency to store more abdominal fat also increases.
As you may know, the higher estrogen levels also increase the risk of prostate cancer. A woman in her premenopausal age has high levels of estrogen (estrogen dominant phase) that results in increased body fat around the hips and difficulty in losing weight. Menopausal women, and of course men with high estrogen, might experience low libido, memory loss, poor motivation, depression, loss of muscle mass and increased belly fat. There are natural aromatase inhibitors to help men out with this condition, but the best approach is to exercise and start losing weight by other techniques so that an increase in testosterone will contribute to overall weight loss. Zinc support and weight training exercise might be beneficial for men to increase their testosterone levels.
7-Irisin
Harvard researchers recently discovered a hormone released by exercise that actually contributes directly to fat loss. This hormone, called irisin, is released by muscles during exercise and transforms white fat cells in the body into brown fat cells. In the studies, irisin also appeared to help in preventing or incapacitating insulin resistance (remember the insulin resistance story). White (yellowish) fat cells are important in storing fat. Brown fat cells that are located in certain areas of your body, in contrast, actually burn fat. They continue to burn "fat" even after you stop exercising - the so-called burning in resting state. Now we are talking about metabolism. This is a very important finding that actually strengthens the role of routine exercise in a weight-loss plan.
So, keep walking for a thinner you.