Harvard experts say one diet type is 'excellent' for a long life

Studies show that around 75% of how long we live is determined by how well we look after ourselves

It's one of the eternal questions - the secret to a long life. According to research, it's actually pretty simple. While of course there will always be a little luck involved, it's mostly down to our own actions.

Experts at Harvard Medical School in the USA said that genetics do play a part - if longevity runs in your family, you'll have a better chance of living longer yourself. But that's only a part of the puzzle.

Actually, they say, the majority of what determines how long we live is what we do ourselves - what we eat, how much exercise we do and so on. The Harvard experts said that generally research had found that around 25% of the human life span was determined by genetics. The rest is down to us.

How we look after ourselves is important, they said, because it's not just about a long life - most of us want a good quality of life alongside longevity.

They added: "There are simple things you can do to be your healthiest, most active, most productive self while living longer. The keys to perhaps living to age 100 or more are a healthy diet, regular physical activity and good lifestyle choices."

Nutrition and a long life

We should all know this - what we eat has a direct impact on our body's cells and therefore how long we last.

The Harvard experts wrote: "A healthy diet provides cells with vital sources of energy and keeps them stable and working as they should. Healthy foods support your immune cells, which defend against infections and other health threats, protect other cells from damage, and help the body repair or replace damaged cells.

"A diet high in sugar, unhealthy fats, and processed foods, on the other hand, can leave cells throughout the body more vulnerable to damage and poor function. This can lead to an increased risk of infection, cancer, inflammation and chronic diseases such as diabetes, cardiovascular problems, and obesity.

"An excellent diet for promoting longevity is a plant-based diet. A study published in JAMA Network Open found that women who most closely adhered to the plant-based Mediterranean diet, which emphasises vegetables (excluding potatoes), fruits, nuts, whole grains, legumes, and fish, and minimises red and processed meat, were 23% less likely to die from any cause than women who did not closely adhere to this dietary pattern."

They explained that a plant-based diet involves lots of fruit, vegetables, seeds, nuts and beans. Go for whole grains instead of processed foods. Foods from plants have lots of good stuff - they are high in antioxidants such as beta carotene, lycopene and vitamins A, C, and E, which protect cells from damage.

The experts were keen to stress that following a plant-based diet doesn't necessarily mean you need to become a vegetarian or a vegan. It just means that the majority of what you eat should come from plants and be minimally processed - you can still enjoy some meat or an indulgent dessert from time to time.

Exercise and a long life

It'll come as no surprise that physical activity promotes a long life. It has many positive effects on the body. This includes boosting heart strength and lung function, improving blood vessel health and strengthening muscles.

Activity can also reduce the chance of a heart attack, stroke, diabetes and other conditions. Exercise can also promote better sleep and boost mood.

The Harvard pros said around 150 minutes a week of moderate activity was suggested, or 75 minutes a week of vigorous movement, or an equivalent combination of both intensities.

They added: "Moderate physical activity includes walking, weight lifting and lower-intensity exercises. Vigorous exercise includes running, bicycling and swimming. Even household tasks like cleaning and gardening count as exercise. So does lifting small hand weights or doing leg lifts while watching TV. The guidelines also recommend muscle-strengthening activities on two or more days per week."

What else can you do to promote a long life?

The experts also outlined other choices we can make to help ourselves live longer:

• Don't smoke
• Limit alcohol
• Get enough sleep
• Hydrate
• Socialise
• Think positively