An apple a day keeps your body toned and slender
An apple a day really does keep the doctor away, claim scientists, after finding that they boost muscles and fight fat.
Researchers have discovered that ursolic acid – a substance found in the peel – has natural body building qualities and could help people keep a toned, slender body.
It could even help with diabetes.
In experiments they discovered that it boosts muscle growth by up to 15 per cent and reduces body fat by more than a half.
It also has health giving properties – reducing blood sugar levels, cholesterol and harmful fatty acids, according to the new study.
Dr Christopher Adams, the study leader at the University of Iowa, said the substance could be especially useful in the elderly who naturally lose body muscle, known as atrophy.
"The old saying goes that 'an apple a day keeps the doctor away'," he said.
"Muscle atrophy causes big problems. It's also very common – it affects most people at some point in their lives, during illness or ageing. But, there's no medicine for it.
"We studied muscle gene activity in people with atrophy and used that information to find chemicals that might block atrophy.
"One of those chemicals was especially interesting. It's called ursolic acid and it's particularly concentrated in apple peels."
The study, published in the latest issue of the journal Cell Metabolism, showed that ursolic acid reduced muscle wasting in mice.
They believe the substance works by reprogramming genes that cause muscle wasting and fat build up.
"Interestingly, although ursolic acid increased muscle weight in mice, it did not increase total body weight, and further investigation showed that mice fed ursolic acid had less body fat than mice that were not fed the compound," he said.
Now they plan to try it on humans to see if it has the same effect.