Doctor's Notes on Obesity
Obesity is a result of the accumulation of excess fat on the body. Obesity is defined as having a body mass index (BMI) of greater than 30. The BMI is a measure of your weight relative to your height. Obesity is considered a chronic disease that has serious long-term health consequences for overall health, and it is a leading cause of preventable deaths in the U.S.
The main symptom of obesity is excess weight. Being obese can cause or increase the risk of other health problems including
- heart disease,
- high blood pressure,
- osteoarthritis (especially knee and hip joint pain, and lower back pain),
- lung disease,
- insomnia from sleep apnea and snoring,
- fungal rashes in skin folds,
- colon cancer, endometrial cancer,
- depression, and
For most people, obesity becomes a lifelong struggle. Obesity is caused by multiple factors, and although the principle of decreased caloric intake and increase in exercise is a relatively simple concept, there are many underlying reasons that lead to obesity in an individual. Treatment, therefore, has to take all of this into consideration. The need to manage obesity is clear as obesity increases your risk of many other diseases and health problems, including the following:
- Heart disease
- High blood pressure
- Osteoarthritis (especially knee and hip joint pain, and lower back pain)
- Lung disease
- Insomnia from sleep apnea (snoring)
- Fungal rashes in skin folds
- Colon cancer
- Endometrial cancer
Depression may be one of the most common effects of obesity. Many obese people suffer emotional distress. Because of the emphasis on physical appearance in our culture, which equates slimness with beauty, obese people may feel unattractive. They also are subjected to prejudice, ridicule, and discrimination, which may make them feel ashamed or rejected.
Obesity is also a major risk factor for the development of diabetes mellitus. The good news is that this may be preventable. In clinical studies, patients who were at a high risk of developing diabetes decreased their risk by almost 60% with less than 10% weight loss in three years.
Weight gain occurs when you eat more calories than your body uses up. If the food you eat provides more calories than your body needs, the excess is converted to fat. Initially, fat cells increase in size. When they can no longer expand, they increase in number. If you lose weight, the size of the fat cells decreases, but the number of cells does not.
- Obesity, however, has many causes. The reasons for the imbalance between calorie intake and consumption vary by individual. Your age, gender, genes, psychological makeup, socioeconomic, and environmental factors all may contribute.
- Genes: Your genes may play a role in efficiency of metabolism and storage and distribution of body fat.
- Family lifestyle: Obesity tends to run in families. This is caused both by genes and by shared diet and lifestyle habits. If one of your parents is obese, you have a higher risk of being obese.
- Emotions: Some people overeat because of depression, hopelessness, anger, boredom, and many other reasons that have nothing to do with hunger. This doesn't mean that overweight and obese people have more emotional problems than other people. It just means that their feelings influence their eating habits, causing them to overeat.
- Environmental factors: The most important environmental factor is lifestyle. Your eating habits and activity level are partly learned from the people around you. Overeating and sedentary habits (inactivity) are the most important risk factors for obesity.
- Socioeconomic factors: Do you live in a neighborhood where it is save to exercise outdoors? Are there supermarket with fresh foods in your neighborhood?
- Sex: Men have more muscle than women, on average. Because muscle burns more calories than other types of tissue, men use more calories than women, even at rest. Thus, women are more likely than men to gain weight with the same calorie intake.
- Age: People tend to lose muscle and gain fat as they age. Their metabolism also slows somewhat. Both of these lower their calorie requirements.
- Pregnancy: Women tend to weigh an average of 4-6 pounds more after a pregnancy than they did before the pregnancy. This can compound with each pregnancy.
- Certain medical conditions and medications can cause or promote obesity, although these are much less common causes of obesity than overeating and inactivity. Some examples of these are as follows:
- Obesity can be associated with other eating disorders, such as binge eating or bulimia.
- The distribution of your body fat also plays a role in determining your risk of obesity-related health problems. There are at least two different kinds of body fat. Studies conducted in Scandinavia have shown that excess body fat distributed around the waist (apple-shaped figure, intra-abdominal fat) carries more risk than fat distributed on the hips and thighs (pear-shaped figure, fat under the skin).
You can manage your weight – and even lose weight – with some simple small lifestyle changes. The following slides will discuss some simple changes you can make to get on the road to a healthy weight.
Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.