News stories frequently discuss causes of obesity. They include imbalances in the hormones leptin and/or ghrelin; continual discovery of more obesity genes; discussions of the phenomenon of infectobesity; and various diseases such as hypothyroidism, Cushing’s syndrome, and polycystic ovary syndrome. Even lack of sleep is reported as a cause of obesity.
All these stories document legitimate phenomena. The problem is that some people read the stories and assume that they apply to their situation. This leads to the conclusion that their weight is outside their control and that it is either impossible to lose weight or it would take a superhuman effort.
Thus, they are defeated before they begin. Their motivation to start on a weight control program is sapped. They resign themselves to the idea that they will just have to live with being fat.
But is this true? Do the conditions described in the news stories apply to you? The answer is: almost certainly not.
The obesity epidemic is a recent phenomenon. One or two generations ago, people were, on the average, much leaner than they are today. This was especially true in countries where the people lived in hardship. For example, in post-World War II Yugoslavia there were almost no fat people.
In America, the rate of obesity has doubled in a generation. In the late 1970’s the obesity rate was about 15%. Now it is more than 30%. What is the cause of this increase?
Changes in our genetic makeup are part of the slow evolutionary process. There is no evidence that a population-wide change in our genes has taken place. Thus, genetic change cannot be the cause of the obesity epidemic.
Similarly there has not been an increase in the diseases that can lead to obesity. If anything, advances in medical science have reduced the incidence of these diseases.
It is generally agreed that the obesity epidemic has been caused by lifestyle changes. Specifically, more ingestion of high calorie foods and less activity in our lives.
So if you are overweight, the number one suspect is your lifestyle.
However, just because lifestyle is the cause of obesity population-wide, it doesn’t necessarily mean that a particular individual is heavy because of lifestyle. How can you be sure that lifestyle is the cause of your weight problem?
Your doctor can tell you if you have a disease that would cause you to gain weight. If it turns out that you do have such a medical condition, then your doctor may be able to prescribe a course of treatment that cures or manages it.
If your doctor cannot find a medical reason for your being overweight, then lifestyle is even more likely to be the cause.
Your doctor does not have the time or the facilities to rule out all physical causes of obesity. For example:
- You may actually have a genetic structure that predisposes you to weight gain.
- You may be one of the few people who has leptin deficiency.
- The microbes in your body may be extra efficient in helping you extract the calories from the foods you eat.
How can you determine whether such factors are playing a role in your weight gain?
One way would be to undergo expensive, state of the art medical tests. But there is a simpler way. For a month or two, rigorously track the calories you ingest each day. Use that information to calculate your average daily calorie intake over that time. Then, compute your basal metabolic rate (the calories you burn to maintain essential bodily functions) and adjust it for your activity level. If your daily intake of calories is more than your computed calorie needs, then the conclusion is definitive: you are overweight because of your lifestyle.
Finally, supposing that you find that you are one of the rare individuals, who eats less than the computation allows, but you still gain weight. This implies that there may be an underlying genetic or medical cause. Is the situation hopeless? No, lifestyle changes can still cause you to lose weight, but it will be more difficult for you than for other people.
The Pima Indians mentioned in chapter one are an extreme example of this problem. Their genetic inheritance is such that they can survive on 700 calories a day. They really do have a “thrifty gene” that causes them to convert food to fat and pack it away on their bodies. Yet even they will lose weight if they eat right and stay active.
In summary, if you are overweight it is almost certainly because of your lifestyle. By all means, check with your doctor to see if there is a medical cause. If there isn’t, the solution is to adopt the SWLL.