However, does that mean that we no longer need to be disciplined about what we eat and how “fat” we are? The answer is a resounding "NO" – we must be careful, but not obsessed, especially about “where we carry that excess fat”.
Research shows that an excessive percentage of body fat is associated with an increased risk for hypertension, diabetes, coronary artery disease (CAD) and hyperlipidaemia (high cholesterol), conditions that can cause premature death. Biomechanical problems such as backache and chronic knee pain are also associated with carrying excess body fat.
Individuals that store most of their fat in the trunk area (referred to as “apple-shaped obesity”) have a higher risk of heart disease and diabetes than those who carry excess fat on the hips and buttocks (“pear-shaped obesity”). A simple measurement to evaluate the degree to which an individual is shaped like an apple or a pear is the waist-to-hip ratio.
This is calculated by dividing the circumference of the waist by the circumference of the hips. Women with values above 0.86 and men with values above 0.95 are at a very high risk of these diseases. Or to make it even simpler: men with a waist circumference of greater than 102cm and women, greater than 88cm are placing their health at risk.
Body fat percentage
A person’s body fat percentage can be another indication of whether they're placing their health at risk. It's important to distinguish between essential fat, the fat that is necessary for survival, and the “extra” unnecessary fat. Fat is found in all cells, surrounds most nerves, and is associated with specific tissues.
Essential fat totals about 3% - 5% of body weight for men and 11% to 14% of body weight for women. However, some “non-essential” fat has a function too. An individual’s body fat can be assessed using any of various techniques. In general, a body fat of over 30% starts to be a health risk, whereas one over 40% becomes a severe risk factor that needs to be appropriately addressed.
The key to successful weight management is a combination of regular exercise and a reduction in energy intake, especially focusing on reducing the intake of unhealthy fats. When weight is lost by diet alone, up to 45% of the weight lost can be muscle tissue, rather than fat tissue, resulting in a slower rate of fat loss.
Exercise helps to maintain muscle tissue, while promoting more fat loss, therefore conserving the metabolic rate and helping with successful long-term weight loss and weight management.
The message is simple, keep your body fat in check and make sure you combine healthy eating practices with a regular programme of physical activity. The result should be a better-quality, healthier life.
- (Kathy Mc Quaide & Angela Paterson, Sports Science Institute of South Africa, updated June 2008)