Doctor claims his body is biologically 20 years younger than his actual age due to his diet

If we were all given a choice about ageing, chances are that most of use would opt to literally be younger for longer.

Dr Mark Hyman, 63, from Massachusetts, is of the opinion that if you eat right, you can reverse the ageing process - and his tips and tricks have gone far from unnoticed, winning him 2.3 million followers on Instagram alone.

The author of the anti-ageing book Young Forever said that it's the type of food that you eat that has the biggest anti-ageing effect on your body.

He said that, for him, the decision to adopt a predominantly whole foods diet has helped him to get into 'best health of my life'.

The doctor specifically follows a Pegan diet and has revealed what this consists of.

The diet is made up of 75 percent of vegetables and fruits - with a particular focus on berries and non-starchy foods.

These are foods which are low on what's known as the glycemic index, and Healthline reports that these can also include cherries, oranges, dried apricots, grapefruit, pears, apples, plums and peaches.

In the doctor's own words 'about three-quarters of your plate should be covered in veggies' and you should 'aim for deep colours.'

He also advised people to 'load up' on healthy sources of fat.

"Whole foods such as nuts, seeds, olive oil, avocados, pasture-raised eggs, and small wild fatty fish such as sardines, mackerel, herring, anchovies and wild salmon contain healthy fats," he said.

"For oils, use extra virgin olive oil (at low or no heat), avocado oil (for higher-heat cooking), and organic virgin coconut oil."

The doctor then explained that you should be snacking on nuts.

When it comes to meat, he said the key is to never treat it like a main course, and if you are plant-based, you should avoid processed powders and fake meats.

Meanwhile, when it comes to exercise, Dr Hyman said that you want to focus on strength-based exercises if you'd like to keep your body 20 years younger like his.

He said 'preserving muscle, building muscle, and optimising function are the keys to the fountain of youth.'

The doctor specifically recommends weight training three days a week and said it will have a profound impact on not only your body but your mind too.

"Exercise strengthens our memory and makes us sharper, happier, and more resilient. Studies show that vigorous exercise is a better anti-depressant than Prozac," he said.

But while following the right diet and exercising are logically good tips for anyone looking to improve their health, the doctor also stressed the importance of sleeping well - which can have the biggest impact on the physical signs of ageing.

"Lack of sleep drives most of the hallmarks of ageing, especially inflammation, mitochondrial damage, and altered hormonal and nutrient-sensing pathways," he explained.

The doctor, like many others, therefore recommends that you should 'aim for eight hours of good quality sleep' and you can help yourself get it by 'sticking to a sleep schedule, avoiding screens before bed, and creating a dark and quiet space'.

The final step in the doctor's advice to to looking younger involves keeping your stress levels to a minimum and making sure you've got a good community around you.

"The most powerful way to stay healthy and connect to your purpose is to be part of some type of community," he sad before advising people to join things like book clubs because those who are 'connected to others live longer'.