Coffee may reduce your risk of type 2 diabetes – but only if you don’t add sugar.
A study looked at the coffee consumption of almost 290,000 people, among whom close to 13,000 developed type 2 diabetes.
They found people who drank black coffee had a 10 per cent lower risk of getting type 2 diabetes for each daily cup they consumed.
The benefit was much the same for those who added milk to their coffee.
But people who added sugar saw this benefit halved – their risk of type 2 diabetes was only five per cent lower per cup of coffee.
This was for people adding an average of one teaspoon of sugar to their coffee.
Coffee drinkers are known from previous evidence to gain less weight as they age, which may reduce their risk of type 2 diabetes.
Caffeine and plant compounds found within coffee may also reduce inflammation in the body linked to type 2 diabetes.
However adding sugar increases the chances of gaining weight.
A study looked at the coffee consumption of almost 290,000 people, among whom close to 13,000 developed type 2 diabetes (stock image)
The study found people who drank black coffee or coffee with milk had a 10 per cent lower risk of getting type 2 diabetes for each daily cup they consumed (stock image)
A calorific cup of coffee with sugar doesn’t fill people up like sugary foods, so they are unlikely to undo the damage by eating fewer calories in their meals and snacks.
Putting artificial sweeteners in coffee was also found to affect its apparent protection against type 2 diabetes.
The reduction in risk of type 2 diabetes per cup was only seven per cent when these were added.
Dr Matthias Henn, who led the study from Harvard T.H. Chan School of Public Health, said: ‘Drinking coffee may help lower diabetes risk, but adding sugar or sweeteners significantly reduces these benefits.’
He added: ‘These differences in consumption patterns provided key insights into coffee’s potential health effects.
‘To maximise coffee’s health effects, consider skipping sugar or any artificial sweetener.’
Researchers looked at female nurses and male health professionals involved in three large US health studies.
These people were asked about their coffee consumption every four years as part of a dietary questionnaire.
People who added sugar to their coffee saw their risk of type 2 diabetes at only five per cent lower per cup (stock image)
They reported their health, including whether they had been diagnosed with type 2 diabetes, every two years.
Followed up for up to 34 years, 13,281 people got type 2 diabetes.
The study set out to understand if coffee additives – sugar, milk, artificial sweeteners and non-dairy whiteners – reduced the protection against type 2 diabetes that coffee appears to provide.
Up to 60 per cent of people across the three studies looked at put some kind of additive in their coffee each day, with up to 42 per cent adding sugar.
Milk in coffee was found to have no effect on type 2 diabetes risk.
Artificial whiteners had no significant effect, although this might not have been seen because there were not enough people who used them in coffee to be able to see a clear link with diabetes.
Every daily cup of coffee, whether it was caffeinated or decaf, reduced the risk of type 2 diabetes by 10 per cent, after taking into account other things like people’s physical activity, sedentary behaviour and family history of diabetes.
But the 10 per cent was ‘significantly’ reduced to five per cent by adding sugar, researchers say added sugar may hit a ‘critical threshold’ to significantly affect their risk of type 2 diabetes.
Researchers did not look at people who added three or more teaspoons of sugar to a cup of coffee, because their study was aimed at people who add a ‘moderate amount’ of extras to their drink Coffee.
The study is published in the American Journal of Clinical Nutrition.
