Health and fitness expert Dr Michael Mosley had a simple habit which can be done for nothing but can make a big difference to your health. The presenter and author died last June but left behind a wealth of help and advice to help people stay as healthy as possible.

And one of his tips in his Just One Thing book can not only cut the risk of heart disease and diabetes but also boost mood and improve sleep. The doctor says starting your day with a 30 minute brisk walk is “life-changing”.

Speaking on his Just One Thing podcast he said: “As well as waking you up, bright outdoor light helps to reset your body clock, which in turn helps to regulate hunger, mood, body temperature and all sorts of other important bodily processes. Light levels outdoors are at least 10 times brighter than inside your house, and when this light hits sensors at the back of your eyes, this sends messages to a part of your brain called the pituitary gland, ordering it to stop producing the hormone melatonin.

“Melatonin is known as the ‘hormone of darkness’ because rising levels in the evening help put you to sleep at night. Studies have shown strong links between poor sleep and weight gain, so maintaining a healthy snoozing schedule is crucial for shedding pounds.”

The expert was known for creating diet plans such as The Fast 800, 5:2, The Way of Life and The Fast 800 Keto. But he also appeared on TV and radio as well as hosting the Just One Thing podcast, prior to his death in June during a holiday in Greece.

His advice has helped thousands of people lose weight with many reversing their diabetes and other health conditions. But his methods were usually straightforward and easy to follow – such as the early morning walk.

Explaining how this helped he told podcast listeners: “As well as exposing you to lots of light, any walk – short, long, fast or slow – will strengthen muscles and bones, reduce joint and muscular pain, burn a few calories and increase energy levels.”

But he added to make it even more effective people could speed it up saying a brisk walk of around 100 paces a minute would increase fitness compared with a leisurely stroll and might even lengthen your life as this increases the heart rate, placing a greater demand on your cardiovascular system.

This helps maintain cardio fitness and lower blood pressure. He added this was the reason brisk walkers have a 21 per cent lower risk of death from heart disease than the more sedentary.

Just One Thing by Dr Michael Mosley, published by Short books at £16.99. Copyright C Dr Michael Mosley 2022