November 9, 2004 

Diabetes, especially Type 2 diabetes, is on the increase worldwide. At least 177 million people worldwide are thought to have some form of diabetes and this figure is expected to double by 2030. This is especially true in Asia: the number of cases of diabetes in India, China, Indonesia, Japan and Pakistan are some of the highest in the world. The rapid rate of increase in the number of cases, which is strongly associated with escalating cases of overweight and obesity has been described as a 'diabesity' pandemic by some observers. The key question is, "is there anything that can be done to slow or reverse this trend". The answer from experts is a resounding "yes!" The evidence is very strong that diet and lifestyle changes can have a huge impact for both whole populations and individuals in preventing onset and/or delaying progression of Type 2 diabetes.  The changes required are not radical or complicated but will take some concerted effort. Read on for some highlights of what is known  about how we can prevent and limit the serious health complications of Type 2 diabetes...

What is Type 2 Diabetes?

Type 2 diabetes, which makes up 90% of diabetes cases, is characterized by high levels of glucose in the blood. Glucose is the main energy source used by the body to fuel almost every action it performs, from breathing and blinking, to exercising and keeping warm. Insulin is produced by the body to control the amount of glucose circulating in the blood by controlling the uptake of glucose into body cells. In Type 2

diabetes, the body cells become rather resistant to the insulin, so the body has to produce very large amounts of insulin in order for the body cells to react and absorb the insulin required for them to function. The high levels of circulating blood glucose, and the large amounts of insulin that are being produced both put serious strains on the body. Without effective intervention to limit these strains on the body, a whole range of serious health complications can develop, such as loss of eyesight, kidney damage, and ulcers. Abnormally high glucose and insulin levels in the blood also result in a much higher risk of cardiovascular disease and stroke. Clearly, avoiding the onset of Type 2 diabetes, or for those who have it - managing it effectively to lessen the damage to the body, is a high priority.

What are the Causes of Type 2 Diabetes?

Type 2 diabetes is more common in some families, but it is avoidable. Although those with a family history of diabetes have an increased susceptibility to developing diabetes, taking active steps to address other risk factors may prevent its onset.

Being overweight or obese is the most important risk factor, and the risk increases over time. Susceptibility also appears to increase with age, so it's important to sustain efforts throughout life. Type 2 diabetes is also strongly associated with sedentary, inactive lifestyles. For example, a recent study published in the Journal of the American Medical Association found a direct link between number of hours of TV watching and Type 2 diabetes in middle-aged women.

Some experts believe that a metabolic make-up which has evolved to help humans survive periods of famine, may, in modern times of plentiful food supply, be working against current generations who live longer and rarely experience hunger. The hypothesis, known as the "thrifty gene" theory, is that insulin resistance is beneficial when food supplies are unreliable because it encourages conservation of fat deposits. However, in the absence of periodic food shortages, the fat deposits are never used up, and as we live longer than our ancestors, the long-term cumulative effects of both insulin resistance and accumulation of body fat are transformed from a health advantage to a health risk. This has particular relevance to many Asian populations who are now experiencing very rapid transition from food insecurity to a food supply abundant of readily available, cheap, high energy food.

Many experts also believe that the greater tendency for Asian nationalities to develop Type 2 diabetes is related to the Asian tendency to accumulate excess fat around the abdomen. On a weight-for-weight basis, fat deposited around tummy increases the risk of developing Type 2 diabetes, far more than fat deposited in other parts of the body such as buttocks and limbs.

Can any special diet help to prevent diabetes?

A lot of research has been devoted to this topic. There is strong agreement that regardless of the makeup of the diet, eating just enough energy (calories) to maintain a healthy body weight is the most effective dietary strategy to prevent the onset of Type 2 diabetes. In 2001, a study in Finland found that the risk of developing Type 2 diabetes was 58% lower in the group that lost weight with a diet and exercise program, than the comparison group who were given no intervention.

The World Health Organisation (WHO) has concluded that the scientific evidence that a diet high in dietary fibre is protective against diabetes is very strong. This provides yet another reason to consume a diet which includes plenty of wholegrain cereals, fruit and vegetables. Related to this, a low glycaemic load diet, that is one which does not create rapid peaks and troughs in blood glucose levels, seems to have some protective role. The relative importance of this in the long term is not yet fully understood, but adds further weight to the advice to substitute refined carbohydrates with high fibre foods (because high fibre foods tend to lower glycaemic load of a meal or snack ) whenever possible.

Research also indicates that exclusive breast feeding in early life reduces the chances of developing Type 2 (and indeed Type 1) diabetes, although, more work still needs to be done to fully understand how and why this is the case.

What is the Latest Research News on Diet and Diabetes ?

There have been some very exciting study results, which indicate that diets rich in some micronutrients might offer some protection but there is still a great deal of additional research to be done in this area before those with, or at risk of developing diabetes, should consider making changes to their diet. Research into potentially protective roles for magnesium (found in legumes, nuts, seeds and green leafy vegetables); chromium (found in liver, brewers yeast, wholegrains, nuts and cheeses); and vitamin E (found in many foods but especially rich sources include fortified margarine, vegetable oils, soybeans and some nuts) is still ongoing.

A recent US study reported that individuals who drank more coffee and other caffeinated beverages were less likely to develop Type 2 diabetes, than those who drank few or no caffeinated beverages. However, authors of the study cautioned that people should not increase their coffee drinking in order to prevent Type 2 diabetes until further studies are completed and analysed.

What about Children and Young People ?

Type 2 diabetes used to be a disease that only affected older people, so much so, it was sometimes called "adult-onset diabetes". During the last decade, however, cases of Type 2 diabetes amongst the younger generation have begun to emerge. Developing Type 2 diabetes in childhood is serious because the earlier the onset, the greater the exposure to abnormal insulin and glucose and fat concentrations in the blood, and the greater the cumulative damage to the eyes, kidneys, heart, etc. All the cases of Type 2 diabetes in childhood and adolescence are associated with obesity and inactive lifestyles, and medical intervention in these cases nearly always includes efforts to encourage better weight management and an increase in daily physical activity levels.

Top priorities for those who wish to avoid becoming one of the 'diabesity' statistics, especially those who suspect they may be at risk, are to get more active, and to lose weight.

What if I already have Type 2 Diabetes?

The actions recommended for prevention are also very beneficial for those with diabetes, as increased exercise, loss of weight and a high fibre diet will all help to lessen the effect of high glucose levels in the blood. In addition, more detailed dietary advice, and regular medical checks are of paramount importance to monitor and improve the management of the condition. For some drug treatment will be necessary, in addition to these diet and lifestyle changes. 

What should I do next to avoid Type 2 Diabetes ?

Increasing physical activity levels will diminish any existing insulin resistance and will also discourage the deposition of fat around the abdomen. Researchers have found that increased physical activity levels, even without reduction in body weight will reduce the risk of Type 2 diabetes. Any increase in physical activity levels will help, but an ideal target to aim for is at least 30 minutes per day of brisk walking, moderate swimming or any other similar exercise.

For those who are overweight, any reduction in body weight will help. Prevention of diabetes has to be approached as a lifelong goal, and so gradual weight loss which can be sustained is the most effective and appropriate strategy. Adjusting your diet to include more dietary fibre, from wholegrains, legumes, beans, fruit and vegetables will have a double benefit as multiple studies endorsed by WHO have demonstrated that high fibre diets not only reduce the risk of developing Type 2 diabetes, but are also extremely effective in weight loss diets.

The diagnostic tests for Type 2 diabetes are very simple and therefore regular screening should become part of your personal health strategy. Doctors report that many people who are insulin resistant or are Type 2 diabetic are not aware of this, sometimes for many years. During this time, the uncontrolled blood glucose and insulin levels will be having a deleterious effect on the body's internal organs and nerves.

Further Reading

Diabetes Atlas (Second Edition), International Diabetes Federation 2003. www.idf.org/e-atlas