Fat adults more likely to have increased insulin resistance, a risk marker for Type 2 diabetes

Jul 6 2005

Adult lifestyle has more influence on your chances of developing diabetes than childhood experience, according to new research whose findings contradict previously-held beliefs.

A team from the University of Newcastle upon Tyne, UK, studied 412 men and women and found that fatter adults were more likely to have increased insulin resistance, a risk marker for Type 2 diabetes.

Childhood factors, such as birth weight and nutrition, were found to have limited impact, whereas they were previously thought to be significant. The study is published in the academic journal, Diabetes/Metabolism Research and Reviews.

Diabetes is a global health problem that is presenting a major medical challenge worldwide. It increases the risk of ill health and shortens life. In the UK alone, diabetes has been said to account for nine per cent of the annual NHS budget - approximately £5.2 billion a year.

There are two kinds of diabetes - Type 1 and Type 2. All diabetes is characterized by raised blood sugar (glucose). In Type 1 diabetes there is an absolute lack of insulin. In Type 2 diabetes, insulin is produced, but the body's tissues are resistant to its action, leaving too much glucose in the blood.

Type 2 diabetes is strongly related to overweight and lack of physical activity, and accounts for 90% of all diabetes. It usually occurs in middle to older aged adults. The World Health Organisation predicts that the number of people with type 2 diabetes will more than double over the next 25 years.

The Newcastle University study measured participants' percentage body fat and waist-hip ratio, along with other lifestyle elements. Men and women with a higher body fat and higher waist-hip ratio were more likely to demonstrate increased insulin resistance.

The data was collected as part of the Thousand Families Study, a Newcastle University project which has examined the health of children born in Newcastle in May and June 1947 throughout their lives. The study was funded by the Wellcome Trust, the Minnie Henderson Trust, the Sir John Knott Trust and the Special Trustees of the Newcastle Hospitals.

Study leader Dr Mark Pearce, who is also director of the Thousand Families Study, said promotion of healthier lifestyles throughout life would be the public health interventions most likely to reduce insulin resistance in later life.

He said: "Previous studies have suggested that risk of poor health in later life is programmed by impaired development in the womb, and that poor growth in fetal and infant life is associated with impaired insulin secretion and sensitivity. However, not all of these studies have not had access to complete data on later life.

"Our study, which has examined people from birth to adulthood, suggests that the life you lead as an adult has the biggest influence on your health, in terms of diabetes risk, in later life.

Dr Pearce, of Newcastle University's School of Clinical Medical Sciences, added: "It's never too late to start living a healthy lifestyle - and even though our study shows that childhood experience had limited impact on insulin resistance in adulthood, parents still have a role to play in introducing their children to eating a healthy diet and physical exercise, so they can develop good habits that will hopefully last throughout adulthood and old age."

Amanda Vezey, care advisor at Diabetes UK, said, "We already know that lifestyle factors play a large part in the development of Type 2 diabetes. This study further emphasises the importance of eating a healthy, balanced diet and taking part in regular physical activity.

"To reduce the risks of developing Type 2 diabetes in earlier years, it's essential to start leading a healthy lifestyle as early as possible."