Fat is essential to human life, but it can also be harmful if there is too much of it. Body fat is a way of storing energy which is essential for the survival of humans. In times of food shortages it can provide the energy for living which can be the difference between life and death.
In much of the World the risk of famine is much lower than for our predecessors. However, our bodies have not undergone significant genetic change in more than 10,000 years. This has important implications for health.
Our forefathers lived very physically active lives, and were only able to eat well irregularly – typically when a hunt had been successful, which created a very short-term glut of food. It was important for them to be able to take in as much nutrition in a short time as possible, and save its energy until the next big feed, which could be days or weeks away. The way the body stored the energy was in fat, which could then be accessed when required.
These days, most of us do not live such exciting lives. We still have the same bodies, but we continuously eat more than we need. The body continues to store the excess in the form of fat. But having too much fat can be dangerous, especially the so-called visceral fat. This is fat which is stored around the organs – not the subcutaneous (or under-the-skin) fat.
Visceral fat is essential to life as it supplies the short-term energy needs of the organs, protects them from high glucose levels and provides a layer of protective padding around them. However, an excess has been found in many studies to be associated with diabetes, cardiovascular disease and a range of other diseases, some of which can have very serious or even fatal effects.
Visceral fat is now recognised as one of the most important things to address in Western health. However, many studies have shown that it is not that easy to dislodge. Diets don’t have much effect, and even regular moderate exercise is only sufficient to prevent the amount of visceral fat increasing. So far the only proven way to reduce visceral fat is regular vigorous exercise.
A review of scientific studies on the subject in 2007 found that aerobic exercise using 10 MET.hours per week was required to reduce visceral fat. This is equivalent to 3 hours brisk walking per week (30 minutes per day, 6 days a week) or 1.5 hours jogging (30 minutes jogging, 3 days per week).
Clearly it is going to take a significant amount of effort to get rid of an excess of visceral fat. But it’s estimated that doing nothing on average increases the amount of body fat in a typical Westerner by 4 pounds per year! That can very quickly put you in the danger zone, so the time to take action is NOW!