We are heading for another global crisis. It is another banking crisis, too. Not money this time but fat laid down around midriffs, bottoms and thighs. The OECD has just released a report showing that developing countries, as soon as their populations begin to join the middle classes, adopt western lifestyles. This means processed foods with transfats, sugars, salts and the rest. It means increased diabetes, heart attacks, early senility and many conditions where the correlations have not yet been done. Going into Accra Mall at the weekend provides you with plenty of evidence for this. Fast food, western style outlets buzz and waistlines increase. The Ghanaian middle classes are not eating a balanced diet. The Daily Graphic today was lamenting the fact that Ghana, which has wonderful potential for feeding itself and exporting far more food to the rest of Africa, was developing a cultural dislike for home grown rice and other commodities.

Meanwhile, watching a programme about the human body, it turns out that if we eat less than 2000 calories a day, we can rejuvenate our hearts and make them 15 years younger! Dieting rats outlive those who can eat whatever they like by up to 33%. That’s a lot. Now we can stuff ourselves like junkies with food that is bad for us and go down with our flags flying, in a hospital bed for months, saying that we preferred fewer years of life but stuffed full of crisps, pizzas, burgers, pre-prepared meals, chips, restaurant meals and the like or we can live many years longer on raw stuff we buy and cook for ourselves.

At the same time, food and water will be what is fought over in the decades to come and western lifestyles and protectionism will increase, exponentially, famine and disease elsewhere. When I overeat, another anonymous person dies.

On the same programme I saw a man who survived seventy odd days in the ocean by eating fish only. If he had been eating, as usual, as a westerner, he would have been dead in days but his brain overwrote his wiring and made him suddenly desire the eyes, liver, kidneys and other bits of the fish carcass that we routinely throw away. All the fish vitamins. The lesson in this was that if we change our eating habits, eat properly but far less, there will be more food for everyone. We would develop a taste for new, healthier foods that we chuck away (currently one third of all food bought in the UK ends up in the bin) or never buy. The body is a chemical machine, not an altar to greed. We need to learn to control it but it is a lifelong discipline.