Calorie counting is less important than eating the right 'medicinal' foods, says bariatric surgeon

“This elixir of life already exists – it is called food,” he says. “But be warned, the door can swing the other way too – this same ‘drug’ can also cause weight gain, obesity, diabetes, inflammation, allergies and misery.

“Like any addictive drug, it can interfere with your reward pathways, make you feel unnaturally high, and lead to addictions and the formation of bad habits – and those bad habits and that unhealthy body become you.”

Despite many people’s obsession with counting calories, Jenkinson, who specialises in weight loss surgery and laparoscopic procedures in London’s Harley Street, believes calories are less important than what food does to your body and brain. He’s adamant that if people treated food as a drug, where certain foods are considered ‘toxic’ and others ‘medicinal’, they would be able to lead a healthier lifestyle far more easily.

“The calories in your food are of secondary importance to your weight and health,” he insists. “It’s what the food does to your body, and just as importantly what it does to your brain, that matters.

“Once you grasp that food works just like a drug, and that the drug can be either medicinal or toxic, your whole outlook on food will change. Armed with this knowledge, you will have the keys to unlock a healthier life, without needing to resort to willpower, because once you understand how food affects you, you will naturally start to crave good food.”

The surgeon, who has outlined the way he believes food affects us in his new book How to Eat (And Still Lose Weight), explains that different components of food carry messages that are interpreted by the body in the same way as drugs. “It’s not the calories in the food that directly shift someone’s weight upwards or downwards – it is these signals,” he says.

Once someone has accepted food is like a drug, they need to learn which are the good food ‘drugs’ and which are the bad ones, explains Jenkinson. “This changes our whole psyche in relation to food – we take on the identity of someone who lives healthily. This type of change is more fun, can be embraced with enthusiasm and does not rely on willpower alone. “

He says we should eat less of food that is high in sugar and refined carbohydrates, sweetened soft drinks, fast food and processed foods, and food containing artificial colourings and flavouring.

However, we should try to have more fish, egg whites, healthy grains, leafy greens, berries and saturated fats such as red meat (though he says to avoid palm oil), and natural spices and salt.

How to Eat (And Still Lose Weight) by Dr Andrew Jenkinson is published by Penguin Life tomorrow, priced £18.99