Losing weight is a futile effort for diabetes sufferers hoping to cut their risk of heart attack or stroke, according to a new study.
Researchers pulled the plug on the decade-long American study this month after finding a rigorous exercise and diet regime made no difference to the risk of a person with type 2 diabetes developing heart disease.
However, AUT University nutrition professor Elaine Rush said this is no free pass to quit the gym and healthy food.
The results are only preliminary and there could be hope for some diabetes sufferers once researchers delve deeper into different groups studied, she said.
Adopting a healthier lifestyle could potentially reduce the risk of heart disease for certain ethnic groups or lower socio-economic groups, she said.
Exercise and diet also boosted people's quality of life, including giving them energy to play with their children, she said.
"People with diabetes also have a responsibility to their community and family to set an example and make people think about what can be done before they get diabetes."
More than 5000 people were monitored in the large American study, half of which were put on an extensive diet and exercise programme.
The study found the chance of a heart attack or stroke was the same for the obese, unfit control group.
The results go against previous advice that exercising and eating healthy would help those suffering from type 2 diabetes.
Researchers acknowledged there were some health benefits in losing weight, including lowering the risk of sleep apnoea and reducing the need for diabetes medication.
Brown University professor Dr Rena Wing, chair of the study, said in a statement the research stopped two years early due to a lack of results.
"Although the study found weight loss had many positive health benefits for people with type 2 diabetes, the weight loss did not reduce the number of cardiovascular events."
Participants lost an average 8 per cent of their body weight after a year, and maintained an average weight loss of nearly 5 per cent at four years.
The study results are still being analysed and are yet to be peer-reviewed.
Previous studies have already shown at-risk adults can prevent or delay developing type 2 diabetes through weight loss. There are more than 200,000 people with diabetes in New Zealand, with type 2 the most common.
Type 2 diabetes is increasingly being diagnosed in adults and children and is related to obesity.
Diabetes NZ recommended people with diabetes lose weight, exercise and eat healthily to manage insulin levels.
- © Fairfax NZ News
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