I really feel for the public today. Constantly bombarded with conflicting nutrition messages and sensationalist health warnings about particular foods or nutrients. Sugar is toxic. Wheat is the devil incarnate. We are designed to eat like our Palaeolithic ancestors. Glycaemic index is the key to health. Intermittent fasting is the best way to lose weight. Carbohydrates cause weight gain. Coffee is bad for you. Coffee is good for you. I could fill up pages with all of the variations of different health messages, some of them coming into and out of vogue as time moves on.

Working in nutrition for many years, I’ve seen all manner of fads come and go. I’ve read thousands upon thousands of research studies looking at foods, nutrients and health. I’ve commented to the media on all manner of diets. And you know what? The entire field of nutrition and health can be distilled down to some pretty simple basics.

A dietary pattern that is made up of mostly unprocessed plant foods and low in highly processed foods, sweets and drinks consistently comes out on top in offering the best long-term health. There is no one food or food group that deserves demonisation. A dietary pattern is a flexible way of eating, not a set of rules that has to be followed.

But there is more to life and health than just food. Just like nutrients are part of the food we eat, food is part of the lifestyle we live. And when it comes to lifestyle, you don’t have to go much further than looking at the similarities between communities around the world that enjoy the longest and healthiest lives.

Described as ‘Blue Zones’, these are areas in the world where higher percentages of people enjoy remarkably long, full lives. Where are these Blue Zones? Okinawa in Japan, the Italian island of Sardina, the Greek island Ikara, the town of Nicoya in Costa Rica and the Seventh Day Adventist community in Loma Linda, California.

Looking from the outside in, some very clear and consistent patterns emerge. People in the Blue Zones nurture strong social networks, consume a mostly plant-based diet, eat in moderation and incorporate daily, natural physical activity into their lives. That’s it.

They don’t exclude all sugar. They don’t calculate the GI of their meals. They don’t ruminate on if the grains they’re eating are stopping the absorption of other nutrients. They don’t ban dairy foods. They don’t take supplements. They eat. They move. They enjoy. They socially engage with their community in person. They live.

You don’t need a PhD in nutrition to be able to effectively choose the best diet for you. You don’t need to latch on to the coat tails of whoever is the diet guru of today flogging yet another breakthrough miracle diet. Take a step back. Learn from the people in the world who have got this mastered