Why Some Races Face Diabetes

Type 2 diabetes risk in ethnic populations partly explained

/ Author:  / Reviewed by: Robert Carlson, M.D

(RxWiki News) There are a number of factors that can boost your risk of diabetes, including ethnicity. However, researchers are still unsure why certain ethnicities have a higher diabetes risk than others.

About half of all people with South Asian, African and African Caribbean backgrounds may develop type 2 diabetes by the time they turn 80 years old, according to a recent study.

The research also gives some clues to why these people have an increased risk of diabetes.

"Exercise to lose weight and be healthy."

For their study, Therese Tillin, MSc, MB, of the National Heart and Lung Institute at Imperial College London, and colleagues looked at the risk of diabetes in British people from different ethnic backgrounds.

They found that twice as many South Asian, African and African Caribbean people developed diabetes by age 80, compared to those with a European background.

While it is already known that people of South Asian, African and African Caribbean descent have an increased risk of diabetes, the causes of this increased risk are still unclear.

In an effort to explain this increased risk, Dr. Tillin and colleagues looked at a number diabetes risk factors. These factors included a family history of diabetes, truncal obesity (carrying fat in the middle of the body) and insulin resistance.

Before people develop type 2 diabetes, they often have insulin resistance - a condition in which the body does not properly respond to insulin.

Insulin is a hormone that manages levels of sugar in the blood. With insulin resistance, blood sugar levels can rise, leading to diabetes and other complications.

Dr. Tillin and colleagues found that family history of diabetes did not explain why South Asian, African and African Caribbean people had a higher diabetes risk than Europeans. However, the combination of truncal obesity and insulin resistance explained why South Asian, African and African Caribbean women - but not men - had a higher risk of diabetes than European women.

Truncal obesity and insulin resistance was only part of the reason South Asian, African and African Caribbean men had an increased risk of diabetes, which suggests there may be other unknown causes of the increased risk in men.

"This study suggests the higher rate of diabetes – a major risk factor for heart attacks and strokes – in some South Asian and African Caribbean women is due to increased levels of obesity, particularly the build-up of fat around the waist, and higher resistance to insulin, which helps the body process sugar," said Dr. Hélène Wilson of the British Heart Foundation, a sponsor of the study.

"This is a very encouraging discovery because it underlines the fact that controlling your weight by eating well and getting active can have a significant protective effect on your health.

There's a wealth of existing evidence that keeping the weight off by eating a healthy balanced diet and being physically active will reduce your risk of heart disease and type 2 diabetes, whatever your ethnic group," said Dr. Wilson, who was not involved in the study.

"Not only does this study increase our understanding of the reasons for ethnic differences in risks of diabetes, it highlights the astonishingly high risk of diabetes in middle-aged people in our ethnic minorities and the importance of early diagnosis and careful management," said Dr. Tillin.

Future studies should look at ways to predict which people are most at risk of diabetes, she said.

"The good news is that diabetes can be prevented if the warning signs are recognized early," she said.

For their study, the researchers followed almost 5,000 middle-aged people living in London. None of the participants had diabetes at the beginning of the study.

The research was published September 10 in Diabetes Care, a journal of the American Diabetes Association.

Reviewed by: 
Review Date: 
September 24, 2012
Last Updated:
October 1, 2012