Obesity is a chronic lifestyle disease that has fast developed into a global epidemic with an estimated 1.3 billion people overweight or obese the world over.

A disturbing fact is that South Africa is rapidly closing in on America as the fattest nation, where obesity used to be considered a problem of developed countries. South Africa's National Obesity Week takes place from 15th to the 19th of October 2009.

Obesity is usually brought about by an imbalance of energy intake and expenditure. In other words you consume more than your body needs or is able to burn off. The excess energy is stored in the form of fat cells which then multiply. Obesity is rarely caused by metabolic or hormonal problems.

How do you know if you are obese?

Obesity can be determined by your body mass index (BMI) which can be worked out by taking your weight in kilograms and dividing it by your height in meters squared. For example: (70 / 1.7 x 1.7) = 24.2 kg/m², that would put you in a healthy body weight.

If your BMI is below 18.5 you would be considered to be underweight, while a BMI between 19 and 24.9 is considered to be of a healthy weight. A BMI of 25 – 29.9 would make you overweight and anything over 30 makes you obese.

Statistics show that nearly half our population is overweight or obese. According to a study carried out by the University of Cape Town's Department of Human Biology in 2003, the highest percentage of obese people in South Africa are African women at 31.8 percent. This demographic is followed by 26.3 percent of Coloured women, 22.7 percent of White women and 21.1 percent of Indian women. White men far exceed any other race at 18.2 percent followed by 8.7 percent of Indian men, 7.7 percent of Coloured men and 6 percent of African men.

Serious health risks

With obesity comes many other health risks, apart from serious physical discomfort and psychological effects. Obesity seriously increases one's susceptibility to life threatening conditions such as heart disease, diabetes and kidney disease. These co-morbidities include illnesses such as asthma, respiratory insufficiency, sleep apnea syndrome, stress urinary incontinence as well as emotional or psychological illness.

Also included in this group of co-morbidities is Venous Status Disease in which the veins are affected. The increased pressure of the large abdomen places pressure on vein valves and causes them to become damaged so that they are no longer able to sufficiently transport blood back up to the heart. This condition is known as chronic venous insufficiency (CVI); the blood pools in the lower legs and can result in pain, swelling, thickening and discolouration of the skin and even ulcers.

CVI also occurs in people that are not overweight due to inactivity and poor lifestyle habits. The calf muscle acts as a pump for our circulatory system to push the blood back up to our hearts. In order for this to happen with ease the calf muscle needs to be exercised. Leading a sedentary lifestyle does your circulatory system and other aspects of your health no favours.

What can you do?

Get active, do some exercise even if you start off with a mild walk — if all you've been doing is sitting on the couch, it will make a big difference. Set yourself realistic goals. Eat healthily being sure to include plenty of antioxidants and roughage in your diet. But most importantly start thinking about your health and taking steps to improve it.

Interested in finding out more about obesity? Read our feature

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