Overweight and obesity are fast becoming a crisis in many countries, and yet it is preventable. Overweight and obesity is defined as the accumulation of excessive body fat to the point where it may affect the health of the individual. Overweight and obesity are classified based on the Body Mass Index (BMI), which calculates the weight-for-height. The BMI is calculated by dividing the body weight in kilograms by the height in meters squared. The figure one arrives at is the BMI, which is then classified as follows:
- BMI less than 18.5 is underweight
- BMI between 18.5 and 24.9 is ideal weight
- BMI of 25.0 and above is overweight
- BMI of 25.0 to 29.9 is pre-obese
- BMI of 30 and above is obese
Worldwide, the rates of obesity have doubled over the last 3 decades. It is the fifth leading cause of death among adults. In Kenya alone, by the year 2008, 13% of males and 24% of females were overweight, while 2% of males and 6% of females were obese (WHO, 2011).
As mentioned earlier, the increase in overweight and obesity has been due to a reduction in the level of physical exercise and an increase in intake of unhealthy foods. Physical inactivity has increased as more people drive to work, where they tend to sit most of the day, and have less time and/or desire for exercise. This is an increasing concern especially with children who have replaced traditional play which was physically exerting, with the more sedentary hobbies such as video games and watching TV. In 2008, it was estimated the approximately 15.4% of Kenyans were physically inactive (WHO, 2010). This sedentary lifestyle has been compounded by the change in dietary habits. The increase in intake of sugary foods and foods high in fat has significantly contributed to the rising rates of overweight and obesity.
So what is the exact health risk posed by overweight and obesity?
Overweight and obesity increases the risk of several diseases including:
- Cardiovascular diseases – the fatty deposits in the lining of the blood vessels (arteriosclerosis) increases the risk of stroke and ischemic heart disease.
- Diabetes mellitus
- High blood pressure
- Musculoskeletal diseases – overweight and obesity increases the wear and tear of the joints with earlier onset of osteoarthritis.
- Some forms of cancer such as breast and colon cancer.
Prevention of obesity
Overweight and obesity are largely preventable, which greatly reduces the risk of developing the associated non-communicable diseases listed above. The reduction of obesity however requires not just the individual effort, but also societal as well as policy changes that will encourage physical activity and healthy eating.
Individuals should reduce the amount of sugar and fat intake, and increase the intake of fruits and vegetables. In addition, it is recommended to engage in 45 mins of exercise atleast 3 times a week. Physical exercise does not have to be going to the gym. Physical activity should be as regular as possible, and is more sustainable if worked into the normal daily routine e.g. walking to nearby destinations instead of driving, taking the stairs instead of the elevator and so on. These activities need to be supported by policies affecting the agricultural and food industry (e.g. reducing amount of sugars and fat in foods), roads and transport (e.g. making pedestrian walkways to encourage and make walking safer), education and labor (e.g. creating awareness of risk of obesity in schools and increasing physical activity in schools and in workplaces).