American nutritionist Nathan Pritikin’s book,  The Pritikin Program For Diet And Exercise, spent a year on the New York Times bestseller list. The program required that you cut out salt, sugar, fat, caffeine and alcohol and limit the amount of red meat in your diet. As a result, it promised, you would live to play tennis with your grandchildren. As one dieter commented, “You may not live longer on the Pritikin Program, but it certainly feels like longer.”

When Nathan Pritikin was diagnosed with heart disease in his 40s he set about finding a way to treat his problem. He researched diets in groups known for their longevity and, in 1975,  founded his Longevity Centre in Miami. The Centre, still being operated by his family, promoted a diet based on high fibre, high carbohydrate, low-fat, plant-based foods and combined this with a gentle exercise program.

Four years later Pritikin’s book was published in hardback form, selling 400,000 copies in weeks. The paperback version came out a year later. At a time when dieting was more about weight loss than about health, Pritikin’s ideas were revolutionary. He was among the first to highlight the association between high-fat diets and high cholesterol and his high-carbohydrate diet contradicted much of the conventional diet advice of the day.

Modern criticism of the Pritikin diet centres around its avoidance of all fats, including healthy vegetable oils, olives and avocados. Some dietitians say the diet is too low in essential fatty acids, although the modern version of the Pritikin diet puts more emphasis on oily fish. The diet also ignores modern advice that cholesterol in egg yolks is not problematic, insisting that only egg whites should be eaten.

With a virtual prohibition on caffeinated beverages and alcohol and by largely eliminating the flavours we’ve grown up to enjoy – which include fats, sugar and salt – the diet is one most of us would find challenging.

Despite following his own precepts, Nathan Pritikin did not live a long life. He developed leukemia and committed suicide at the age of 70.