News

NEW Services Provided by Endocrine Consultants (Feb 2010)

We now offer a cardiometabolic program which allows us to identify and treat metabolic abnormalities, as cholesterol problems, which substantially increase the risk of heart disease. To find out more about our new service click here.

New Thoughts on Weight Management

Perhaps few aspects of healthcare are as frustrating for people as weight management.  There are so many opinions out there about weight loss, and much of the publicity leads people to believe that there are simple approaches that they should be able to follow that would lead to quick and permanent weight loss.  In fact, nothing could be farther from the real scientific evidence.  New research is giving us important insights into how the body regulates appetite and weight, and this appears to be a much more complex problem than almost anyone thinks.

The first issue is how different the real needs in diet and exercise are for most adults versus what they perceive.  Because of the way Americans live today, we probably burn fewer calories per day than any other population.  We walk less than other industrialized societies, in part, because our cities are not laid out like cities in Europe, where people walk much more than we do.  The half hour of real exercise someone gets at a gym is good, but it does not usually burn as many calories as people think.  That is usually balanced by how many calories per bite sit in many of the foods we Americans like to eat, as steak, fried food, and gravies.  So for us, the margin between weight loss and no weight loss is very small, and just a slight deviation from good food selection one day per week can prevent effective weight loss over a long period of time.

However, we also now know that there is much more to weight management than increasing exercise and decreasing caloric intake.  We have learned that there are various hormones secreted in the body under different circumstances, which affect appetite control.  We have also learned that there may be hormones, such as the hormone leptin, which influences how fast we burn calories.  So weight management may not be a question limited to what foods we eat or how much we exercise.  It may include other factors, which influence the secretion of hormones, which affect our appetite or our rate of caloric burn.

Insomnia is an example.  When people do not sleep more than 7 good hours per night, their stomachs make a hormone called ghrelin, which is a primary stimulant of the appetite.  Depression or certain drugs for psychiatric illness can substantially stimulate the appetite.  Sunlight, exercise, and eating low fat foods may stimulate the secretion of brain hormones, which tend to decrease the appetite.  Women, who are menopausal, may gain weight if they do not maintain adequate supplementation with estrogen replacement, because a lack of estrogen may render the appetite receptor in the brain less responsive to at least some of the hormones, which turn the appetite off.

These concepts reflect only a part of a growing literature on the science of appetite regulation and weight maintenance.  Our Center is working hard to adapt scientifically valid approaches from these concepts into the care of our patients.

New “High Tech” Program for Weight Management in Diabetes and Related Conditions

At long last, new concepts are emerging to explain in part some of the most challenging and difficult issues people experience in regards to weight management and its influence on diseases like diabetes and metabolic syndrome. These new theories entail new information about two key hormones in weight management: insulin and leptin. Insulin, of course, is the hormone, which regulates blood sugar levels. In fact, it strongly influences many aspects of metabolism. However, it also appears to be a primary signal to the appetite center in the brain to turn off. Thus when a person eats, and the pancreas increases the secretion of insulin, the insulin goes to the appetite center and tells it that the person has had enough to eat. Interestingly, the hormone leptin, which is secreted in fat cells, does the same thing. Its secretion is stimulated by insulin, so the more insulin a person secretes, theoretically, the more leptin the person secretes. Since leptin and insulin do essentially the same things to appetite, why are there two extremely similar signals to the brain in terms of appetite regulation? The answer appears to be that there are important sex differences in the actions of each hormone. Leptin is the primary signal to turn off the appetite in women, whereas insulin is the primary signal in men. When a woman makes too much male sex hormone, as in polycystic ovary syndrome, it appears that her leptin becomes less effective. Similarly, a woman who goes through menopause and does not take estrogen replacement can have her hormone balance shifts in favor of male sex hormones, and the leptin becomes less effective. Since insulin is only a “back-up” signal in women, the woman then gains weight. In addition, when insulin is the primary driver of appetite regulation, the person shifts body fat from the thighs to the abdomen, and the woman starts to assume the shape more of a male than a female.

The opposite occurs in the man. In men, insulin is the primary signal of the appetite, and leptin is the back-up. When a man gains weight, his fat cells make an excess of estrogen, and insulin becomes less effective. This leads to a decreased ability to turn of the appetite, and the man gains weight. As men age, many have a decrease in male sex hormone production, leading to a relative decrease in the ratio between male and female sex hormones. Here again, the insulin signal becomes less effective, and the man gains weight.

A number of other hormones have been identified, which are secreted after eating and decrease the appetite. These include amylin, GLP1, and cholecystokinin. There are now commercial forms of these on the market, or synthetic forms are in clinical trials. In addition, there are now clinical trials with the hormone, leptin. Two drugs, metformin and buproprion, each increase the secretion of a hormone which decreases the appetite. In some patients, each of them has been found to help with weight loss. However, neither drug is indicated for weight loss. Metformin is used in diabetes and insulin resistance, and buproprion is an anti-depressant.

Very recently, some intriguing data was published about insomnia. People with insomnia have been shown to gain weight. It appears that this weight gain is due, at least in part, to an increase in the secretion of a hormone called ghrelin, which is a potent stimulator of the appetite. Treatment of the insomnia may prevent its weight gain.