A nutrition professor has lifted the lid on what has helped him reach 100 years of age. Dr John Scharffenberg is an expert at Loma Linda University in California.

He was born in Shanghai, China, in 1923, and graduated from Harvard’s School of Public Health in 1956. He has been a professor at Loma Linda for a remarkable 63 years.

Dr Scharffenberg has outlived his two brothers by 14 and 17 years – and he says that number is only going to go up as he is ‘not going to die next year’ either. The secret of living so long? In Dr Scharffenberg’s opinion, the answer is simple: exercise.

He said: “We need to exercise every day. That’s very important. I have outlived my two brothers – 14 years, 17 years. They’re already passed away, and every year that’s going to increase another year, because I’m not going to die next year, so it’s going to keep going up.

“I had a lady who helped me with the PowerPoint lectures, She was a graphic artist. She did a lot of work for me, but she was kind of big – I mean, big big. I said to her one day. ‘you know, I’ve got to talk to you about your weight. I’m a preventative medicine doctor, I must talk to you’. Her face fell. I said, ‘do you want the bad news first or the good news first?’ She says, ‘tell me the bad news first’.

“I said, ‘you should understand that being overweight increases the risk of dying from almost every disease we know. But now let me tell you the good news. Even though you are obese, if you exercise every day, you will live longer than the woman who’s normal weight who does not exercise.

“A man who smokes, has hypertension, has high blood cholesterol, but if he exercises every day, he will outlive the man who doesn’t have any of those problems who doesn’t exercise.”

We have long known that exercise is great for us. Harvard Health says: “If you’re physically active, your heart gets trained to beat slower and stronger, so it needs less oxygen to function well; your arteries get springier, so they push your blood along better; and your levels of “good” HDL cholesterol go up.

“It’s also not much of a surprise that physical activity helps prevent diabetes. Muscles that are used to working stay more receptive to insulin, the hormone that ushers blood sugar into cells, so in fit individuals blood sugar levels aren’t as likely to creep up.”

It can also help prevent cancer, particularly breast, colon, and endometrial. Three studies have found that if you’ve had colon cancer or breast cancer, physical activity reduces the chances of it coming back.

It even helps the brain, with studies showing it can help overcome depression in ways similar to antidepressant medications, while it can also delay the slide of cognitive decline into dementia – and help those already suffering from it.

THe NHS satsa that ‘exercise can reduce your risk of major illnesses, such as coronary heart disease, stroke, type 2 diabetes and cancer, and lower your risk of early death by up to 30 per cent’ It recommends that adults should try to be active every day and aim to do at least 150 minutes of physical activity over a week, through a variety of activities..

One study published in the journal Circulation found that meeting the minimum physical activity guidelines (150–300 minutes of moderate-intensity or 75–150 minutes of vigorous-intensity exercise per week) can reduce the risk of early death by up to 21 per cent. Increasing this amount to two to four times the minimum can further lower the risk by up to 31 per cent.