In Dr Joel Fuhrman's world, you don't need to count calories to lose weight. Rather, the 59-year-old former world-class figure skater suggests you keep tabs on maximising micronutrients while eating as much as you want - as long as it is plant based.
In other words Fuhrman recommends you turn vegan - which, in Eat to Live, his New York Times #1 bestseller first published in 2003, he promises will help you lose at least 9kg in six weeks.
It helps that Fuhrman, who has a medical degree specialising in nutritional medicine from the University of Pennsylvania, enlisted the help of six guest chefs to boost his culinary repertoire.
The chefs include Martin Oswald of Pyramid Bistro in Aspen, Colorado - the first so-called "nutritarian" restaurant in the US. There's also Jack Hunt, who was the executive chef at one of the many cafes at Google's headquarters.
Nutritarian is Fuhrman's term for his plant-based, nutrient-dense diet, which research shows can aid fast and sustained weight loss, reverse disease and promote lifelong health. The diet's foundation is Fuhrman's formula for health: nutrient intake divided by calorie intake. The bigger the number, the better - it means the food has more vitamins, minerals and phytochemicals, all of which have no calories but are vital for well-being.
He has devised the Aggregate Nutrient Density Index (ANDI) to rank foods according to their micronutrient density per calorie. Kale, collard greens, mustard greens and watercress get the highest score of 1,000. Vanilla ice cream (nine), corn chips (seven) and cola (one) languish at the bottom of the list.