What's better than starting your day with a cup of hot coffee? That doing so can help fight obesity and diabetes as well.

A recent study has found that drinking a cup of coffee can stimulate 'brown fat', the body's own fat-fighting defences, which can fight against obesity and diabetes. Published in the journal 'Scientific Reports', the study is one of the first to be carried out in humans to discover components that can have a direct effect on 'brown fat' functions, an important part of the human body, which plays a key role in how fast calories can be burnt into energy.

Brown adipose tissue (BAT), also known as brown fat, is one of two types of fat found in humans and other mammals. Initially only attributed to babies and hibernating mammals, it was discovered in recent years that adults can have brown fat too. People with a lower body mass index (BMI) therefore have a higher amount of brown fat.

Professor Michael Symonds, the University of Nottingham who co-directed the study said, "Brown fat works in a different way to other fat in your body and produces heat by burning sugar and fat, often in response to cold. Increasing its activity improves blood sugar control as well as improving blood lipid levels and the extra calories burnt help with weight loss. However, until now, no one has found an acceptable way to stimulate its activity in humans."

The team started with a series of stem cell studies to see if caffeine would stimulate brown fat. Once they had found the right dose, they then moved on to humans to see if the results were similar.

The team used a thermal imaging technique to trace the body's brown fat reserves. The non-invasive technique helped the team to locate brown fat and assess its capacity to produce heat.

"From our previous work, we knew that brown fat is mainly located in the neck region, so we were able to image someone straight after they had a drink to see if the brown fat got hotter," said Symonds.

"The results were positive and we now need to ascertain that caffeine as one of the ingredients in the coffee is acting as the stimulus or if there's another component helping with the activation of brown fat. We are currently looking at caffeine supplements to test whether the effect is similar," added Symonds.

"Once we have confirmed which component is responsible for this, it could potentially be used as part of a weight management regime or as part of glucose regulation programme to help prevent diabetes," said Symonds.