Obesity is the presence of excess body fat. It develops when energy intake exceeds energy expenditure over a prolonged period of time, leading to an accumulation of body fat. It can be defined in terms of body weight relative to height referred to as the Body Mass Index (BMI) and calculated by dividing the weight in kilogrammes by the square of height in metres.
Central obesity is best measured using waist circumference. The absolute waist circumference of greater than 102 cm in men and greater than 88 cm in women or waist to hip ratio of greater 0.9 for men and greater than 0.85 for women are used to determine central obesity which also comes with health risks. For children under the age of 18 or 20, there are weight charts that help to determine whether they are overweight or obese.
Causes of obesity
1. Sedentary habits and lack of exercise. Spending more time watching television and working at the computer, doing schoolwork or passive leisure activities and depending on cars and motorcycles instead of walking, fewer physical demands at work or at home because of modern technology, urbanisation and lack of physical education classes in schools, have led to obesity.
In other words, people who are inactive are more likely to gain weight because they don’t burn the calories that they take in from food and drinks. Research has shown that more than two hours a day of regular inactivity is linked to overweight and obesity.
2. Unhealthy diets with too much fat and sugars.
When you eat more than you use, it is stored in your body as fat.
There is a household shift from eating coarse cereals, vegetable and fruits to eating highly refined and processed foods containing higher sugars and saturated fats and dairy products.
3. Excessive alcohol consumption. Studies have shown that alcohol per se has a lot of calories second to fat in hierarchy and it also increases appetite leading to overeating and making unhealthy food choices.
4. Genetics factors. Additionally, some cases of obesity are familial meaning it runs in the family or it is in the genes. These kinds of people inherited obesity genes from close relatives.
5. Hormonal imbalance. This can result from causes such as hypothyroidism where the thyroid gland produces little thyroid hormone. Lack of or little thyroid hormone slows down metabolism and causes weight gain. Another example is Cushing’s syndrome where there is over production of steroid hormones in the adrenal gland. Cushing’s syndrome can also develop if a person takes high doses of certain medicines such as prednisone for long periods.
Additionally, women with polycystic ovarian syndrome are often obese. This condition that affects women of childbearing age due to high levels of androgens and also presents with excess hair growth and have reproductive problems and other health issues.
6. Emotional state. Some people eat more than usual when they are depressed, angry, stressed or bored. When this continues for a long period of time, the overeating will lead to weight gain and may cause obesity.
7. Medicines. Certain types of medications such as corticosteroids, antidepressants, and epilepsy medicines taken for longer periods of time may cause one to gain weight by slowing the rate at which the body burns calories, increasing appetite or causing the body to hold onto extra water.
8.Pregnancy. During pregnancy, women gain weight to support their babies’ growth and development. After giving birth, some women find it hard to lose the weight. This may lead to overweight or obesity, especially after a few pregnancies and with increasing number of childbirths especially for women
9. Age. In both men and women the occurrence obesity increases with age. The older you become the more muscle you lose, especially if you are less active. Muscle loss can slow down the rate at which your body burns calories, hence leading to weight gain.
Health complications associated with obesity
Obesity is a serious health problem that can harm one’s health and should be taken seriously. It is known to reduce life expectancy due to the fact that it increases the risk of developing Type 2 diabetes, hypertension, high blood cholesterol, stroke, heart attack and heart failure.
It has also been implicated in the development of gall bladder stones, gout, osteoarthritis involving the knees, hips and the lower back, sleep difficulties, varicose veins, postoperative complications and menstrual abnormalities.
Certain types of cancers particularly cancers of the colon, rectum, prostate, breast, uterus have been associated with obesity.
By Dr Tino Salome Ongu
Medical Research Council in Entebbe.