Obesity is escalating at a rate that in 20 years time there will be over 700,000 additional cases of cancer, says Sophie Borland, Health Correspondent for the Daily Mail. Obesity is going to be the norm in the future in most developed countries. Obesity related illnesses including diabetes and heart disease will cost the government health budgets and most health charities urge governments to take tougher actions.

According to David Ludwig, obesity expert and professor of nutrition at the Harvard T.H. Chan School of Public Health, overeating doesn't make you fat. The process of getting fat inherent in your body makes you overeat. This may sound 'Irish' as a century of science supports the view that cutting back on calories makes the situation worse.

No wonder people say, "I don't eat much now as before, but still I can't lose weight to flatten my belly". Some people eat a lot of food but they remain within the normal ranges of body weight (BMI), whilst others eat little and become overweight. They may be considered belonging to different metabolic types.

It is a fact that when you cut down on your quantum of daily food you get hungry and slows down your metabolism (engines working inside our body). Further, we eat the wrong type of foods which upsets the gut microbes, and throws our hormones out of balance, and sets in more hunger pangs. Then, we eat between meals irregularly and eat more food.

Health charities suggest banning junk food adverts between 6am and 9pm. That may reduce the incidence of mainly young people consuming hot foods.

By over-eating, the fat cells do get fat with plenty of calories, but there are fewer calories in the blood stream according to David Ludwig. On eating less food fat cells will be starved of calories and very much less calories are found in the blood stream. So it won't work. The craving is to eat more and get fat, as the brain recognises the calories in the blood stream and not of the fat cells. What this means is that you could eat and eat and fill the fat cells with calories and the brain may not recognise the situation.

According to David Ludwig, if the fat cells are storing too many calories, the brain doesn't have access to enough to make sure that metabolism runs properly. So, the brain makes us hungry in an attempt to solve that problem, and we overeat and feel better temporarily. If the fat cells keep on taking too many calories through eating excess food, we get stuck in this never ending cycle of over eating and gaining weight.

Leaving aside this theory, for most of us eating excess food add on fat and especially round the waist line. The only way to lose a significant amount according to Michael Esco, professor and co-director, Human Performance Laboratory at Auburn University, especially if you have a lot – is to burn more calories than you consume, through exercise and restricting your carbs.

Again, this may not work for some people to solve their obesity problem.

It is the low fat, very high carbohydrate diet that we all eat that causes the obesity which raises levels of the hormone insulin stimulating the fat cells to accumulate fat and calorie overdrive. Insulin could be the ultimate fat cell fertiliser, according to David Ludwig.When you eat too many carbs per meal more insulin is secreted by the pancreas and sent out into the blood stream to courier blood glucose to the fat cells and the liver. If you don't have enough insulin secreted as in diabetes the fat cells may not get sufficient to store. So, it is the insulin that is the culprit for obesity. Insufficient insulin secretion as in type 1 diabetes you tend to lose weight until insulin therapy is commenced. Under normal situation cutting down on sugars is the quickest way to reduce weight as the demand for insulin is very much less.

Reducing the amount of sugar in soda drinks and fruit cordials may reduce the obesity problem to some degree. In New York the mayor banned teenagers purchasing soft drinks and that has shown positive results

Studies at Queen Mary University of London have shown that the average adult would consume 38 fewer calories a day and lose just over 2 lb, on cutting down daily on soft drinks consumption.

Do gut microbes influence obesity?

Studies on mice have shown that the good gut microbes may contribute to weight gain. An experiment on the human twins, one was thin and the other one obese, whose gut bacteria were transferred them into lean mice. The mice with bacteria from fat twin grew fat, and the bacteria taken from the lean twin remained thin.

Now one could explain why diet restrictions may not lead to weight loss. If the gut microbes responsible for obesity can be identified, it would in time be easy to control weight through replacing them with other microbes that do not cause the problem, and with faecal implants.

Overweight people are at no greater risk of dying than people of normal weight.

It is possible that increased body fat provided metabolic benefits that protect the heart, or that having extra reserves of fat could be helpful for those whose sicknesses make it hard to eat.

Lead researcher Katherine Flegel, of the US Centers for Disease Control and Prevention, or CDC, published a controversial study in 2005 that indicated there was a link between excess weight and living longer.

Small amounts of excess fat "may provide needed energy reserves" during illness, or help in other ways that need to be investigated, wrote biomedical researchers Steven Heymsfield and William Cefalu in an editorial also published on Tuesday in the JAMA.

"Not all patients classified as being overweight or having Grade One obesity, particularly those with chronic diseases, can be assumed to require weight loss treatment," they emphasised. This is a relieving factor for those mild obese subjects reading this article. If you are a diabetic it is reasonable to control one's weight to within the normal range.

Are there any obese Vegans?

Yes, plenty of them. How can we account for such situation when they live on vegies alone? It is possible that genes play a part, and further eating fried spicy food regularly, without much exercise may be a factor. They, too claim that they live longer.