The Metabolism Story

The Metabolism Story

I am asked this question a lot. The short answer is an abnormal resting metabolic rate. The long answer is more complex and will need some explaining. The following is a generalized explanation of the reasons behind obesity and weight management. I hope it answers the question for you.

The human body is very efficient at utilizing energy (calories). The calories a person ingests (caloric intake) is measured against the energy utilized by the body for normal activity (resting or basal metabolic rate=BMR). The brain determines how much caloric intake will be needed to maintain the current BMR. Additional calories (energy) will be set aside for later use – stored in muscle and liver as Glycogen or in adipose cells as lipids=fatty tissue. When energy is not available, the body will utilize the stored calories for metabolism. The truth is that the body will never easily give up this preserved energy it worked so hard to store. Nature has created such an efficient machine that the body would rather digest its own muscle and connective tissue before depleting these valuable (fatty tissue) energy deposits. The reason for this is simple. Humans are designed for famine survival.

When food is scarce (local restaurants and supermarkets are closed) only those individuals with a fuel efficient system will survive. The body’s first priority is to prepare for a prolonged famine. To achieve this goal the body utilizes the glycogen sources first. This usually will provide energy for only 1-2 days. If starvation (less than 800kcal/day) is prolonged then the body begins to metabolize body proteins including muscle fiber and connective tissue and muscle wasting begins. Muscle wasting is what gives a person a gaunt, hollow appearance of malnutrition. Surprisingly the human body can maintain a severe obesity state, but be severely malnourished at the same time.

During a low caloric intake period of diet or fasting, the body will dramatically lower the resting or basal metabolic rate which means that energy for daily activities is limited. This causes feelings of fatigue, and lack of energy and results in less activity to avoid any unnecessary protein break down. If the caloric intake remains low, the body will deplete more muscle proteins and connective tissue. Only after significant amounts of body proteins are depleted will the body utilize the fat stores that it preserved for just this purpose.

There is very little an individual can do to alter these facts. This strategy is good for famine, but what does this mean for people not exposed to daily starvation and who have access to unlimited calories at any time of day or night? Obesity! The human body has not changed its ways just because food is plentiful and widely available.

A few “blessed” individuals have genetically higher metabolic rates and can consume more calories without the body storing the excess as fatty tissue. The majority of us, on the other hand, have metabolic rates that will change depending on caloric intake. We also need to understand that our basal metabolic rate changes with age and activity levels. Our early years usually lead to unlimited caloric consumption (overeating) and these eating habits become well ingrained. Then we grow older and our BMR begins to slow. If eating habits are unaltered the body begins to store all that extra energy as fatty tissue which leads to obesity.

So, if this is all natural then how do we fight nature?

The answer seems simple, consume fewer calories. The problem is, if an individual can restrict their diet then two things usually occur. The body senses starvation mode and decreases the BMR. The brain senses famine and stimulates the search for food (hunger). Fad diets and “starvation approach diets” leads to short term weight loss but will lower the BMR. Once the hunger issue sets in, most will eventually succumb to the urge to take in larger than normal volumes of food (binge eating).

Once we have “failed” our fad diet, we realize that any short term weight loss has been offset by weight regain usually at a weight more than where we started. Frustrating isn’t it?

Industries and markets have been created to convince individuals that there is an approach to circumvent this process and that all it takes is money. If you buy the perfect meal plan or medication, then the weight will fall off without hunger issues and will stay off forever. These plans are expensive and usually don’t appear to work for anyone except the individuals used as spokespeople hired to sell the idea.

So, is there any hope? Yes! Is it hard? Yes! Does it take time and energy? Yes! Is it expensive? It doesn’t have to be. Let me explain.

In my opinion there are 3 main reasons for weight gain.

  1. Food selection. High calorie, nutritionally poor foods that are high in carbohydrates tend to stimulate hunger. Eating this type of food usually does not lead to a sense of fullness until large quantities are consumed. An easy solution is to increase protein food selections. High protein diets will usually decrease hunger for longer periods.

  2. Eating Behavior. Eating the right foods, but in the wrong way can still lead to weight gain. Skipping meals is the most common mistake. This leads to lowered BMR and increased hunger. The hunger peaks in the evening and high calorie intake before sleep may lead to increased conversion of calories to fatty tissue.


Grazing is also a common problem. By eating smaller portions the satiety centers are not triggered and a perpetual mild hunger state encourages continued eating. An easy solution is to eat 3 meals a day. A small breakfast is better than no breakfast. A low sugar protein bar is a good between meal snack or meal replacement selection.

Eating a very large meal also tends to increase the amount of calories consumed and since we tend to eat quickly, the satiety centers in our brains are not triggered until our stomachs are beyond full. This results in feelings of extreme fullness 15-30 minutes after meal completion.

  1. Metabolism. Decreasing calorie intake will lower your metabolism. Increasing calorie intake will raise your metabolism to your base line. I am sorry to say that there are no medications or special diet plans that I am aware of that maintain metabolic rate for everyone. Exercise and muscle mass are the predominant variables in determining BMR. As little as 10 minutes of structured daily activity (treadmill, stationary bicycle, elliptical, etc.) daily has been shown to maintain resting metabolic rate at a normal level. The addition of 30-40 minutes of strenuous cardio activity (breaking a sweat) will burn calories and accelerate weight loss. The individual that exercises 5-10 minutes daily will have a higher metabolism then the individual that exercise 30 minutes twice a week. (Frequency is more important than duration when discussing metabolism)

Advantage to Indirect Calorimetry Testing


Basal metabolic rates (BMR) can be tested (indirect calorimetry) in the office setting and can indicate whether dieting is a good idea for weight loss or if utilizing mechanisms to increase the metabolic rate is a better option. If the BMR is above 2,000 Kcal per day than reducing caloric consumption will result in weight loss that will be primarily adipose tissue.

If a patient continues to consume fewer calories and their metabolic rate is too low (less than 2000 Kcal/day) then the patient will not be able to achieve any significant weight loss other than muscle wasting.

In Summary, diet and exercise should not be considered temporary events only to be tried before weddings, beach vacations or high school reunions. A common sense approach to eating right and daily activity will usually halt weight gain and may facility weight loss in most of us. The down side is that following this approach will cause increased hunger issues for a large majority of the population. The control of hunger can be manipulated to some extent by protein rich diets and eating behaviors, but some people will benefit greatly from appetite suppressants. Appetite suppressants come in many shape and sizes with different side effect profiles. A safe, effective regime can usually be found for each individual, but that is another story and a different article. There are also a few proven natural supplements that may help some individuals maintain or even increase their metabolism.

Best Regards,

Dr. Russell Gornichec

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