In the UK at the moment around 60% of adults are either overweight or obese and over the next decade things are likely to get even worse. I am often asked why this is, what has happened over the last three decades to produce such a serious public health problem?
To understand the origins of the current epidemic you have to understand how we evolved. For most of our life on earth, we have had only intermittent access to food. There were periods in human history when food was extremely scarce (and still is for many millions of people). As with any animal for whom access to food is unpredictable, we developed mechanisms which helped us survive. First, we have an amazing ability to store fat as a source of energy. This helped us survive when we had to go without food for long periods. Secondly, when food became available, we were hard-wired to eat as much as possible. And thirdly, after eating we were programmed to be as idle as possible, so as to preserve our stored energy. Other than in pursuit of food, we have no desire to be physically active. One can see this in wild animals today. Lions will go many days without eating but when eventually a kill is made, they eat as much as possible and then conserve energy by sleeping and lying around. So the cause of the current obesity epidemic can be summarised in one sentence: We have a powerful biological drive to eat as much as possible as often as possible, but no biological drive at all to be physically active.
If we now fast forward into the 21st century what has changed? It is obvious that the availability of food is the really big difference. Most of us rarely go more than a few hours without eating and high-calorie food is available 24 hours a day. The problem is that the biological mechanisms which were so important to our survival have not changed. We are still hard wired to eat as much and as often as possible, and to be as inactive as possible. The reason why we find it so difficult to lose weight is because we are being asked to limit our food consumption and to be as physically active as possible – precisely the opposite of what we have been hard-wired to do!
Fortunately, genetics is not destiny and it is possible to re-programme our habits in such a way as to achieve and maintain a healthier weight. This is precisely what the Weight to Go weight loss plan is designed to do. By providing a nutritious diet with optimal protein intake, it allows you to feel fuller longer and to lower your total calorie intake. If you combine this with some regular walking you will lose weight – and maintain it*.
Dr David Ashton
12th October 2011