In the 24-week ‘starvation’ portion of the study rations were cut substantially to only two Spartan meals per day, designed to approximate the food available in European famine areas (a heavy emphasis on potatoes, cabbage and whole-wheat bread and very little meat). The subjects not only lost a considerable percentage of their body weight, but suffered a number of problems as well. They thought ceaselessly about food, became lethargic, depressed and cold, and developed bleeding disorders. Their ankles became oedematous and some developed psychological problems. They were consuming macronutrients in the following amounts daily: protein 100 grams, fat 30 g and carbohydrate 225 g (25.5% protein, 17.2% fat and 57.3% carbohydrate). Average energy intake was 1 570 calories per day.
In the late 1960s John Yudkin’s group at the University of London did a study that is most interesting in view of Keys’ findings. For about 15 years they had been running a weight loss clinic using a low-carb dietary approach. The patients did well, but Yudkin received the usual criticisms faced by those who treat obese patients by restricting carbohydrates. His peers also said his diet didn’t provide vitamins and minerals required for health. So he decided to do a study to see if there were in fact inadequacies.
Yudkin recruited 11 subjects, instructed them in the basics of low-carb dieting, and followed them up for 2 weeks. The subjects were told to consume between 300 and 600 ml milk daily and as much meat, fish, eggs, cheese, butter, margarine, cream and leafy vegetables as they wanted. The amount of carbohydrates in other food was limited to 50 g a day. Not only the subjects’ food intake but their mental status was evaluated.
None of the subjects complained of hunger or any other ill-effects; on the other hand, several reported an increased feeling of well-being and decreased lassitude. Their macronutrient intake was 83 g protein, 105 g fat and 67 g carbohydrate (21.3% protein, 60.6% fat and 17.1% carbohydrate). Energy intake was 1 560 calories per day, almost exactly the same as in the Keys study.
These people were given all the food they wanted. They weren’t forced to drop their calories to 1 560 per day – they did it spontaneously because they were satiated.
Both studies provided about the same amounts of calories, but with huge differences in outcome. In the Keys’ semi-starvation study (high-carb, low- fat) the subjects starved and obsessed about food constantly. In the Yudkin study (low-carb, high-fat) the subjects, who had no restriction on the amount of food they ate, voluntarily consumed the same number of calories as the semi-starvation group, yet reported an increased feeling of well-being. Instead of the lethargy and depression that plagued the Keys subjects on their low-fat, high-carb 1 570 calories, those on the same number of low-carb, high-fat calories experienced decreased lassitude. Maybe it’s not the number of calories that makes the difference, but their composition.
In the end, don’t use calorie counting as the main criterion when you choose food. Eat food high in nutrients. Much nutrient-dense food is in fact ‘diet food’: fish, fruit, vegetables, seafood. ‘If Americans choose foods based on nutrient density,’ says Eileen Kennedy, dean of the Friedman School of Nutrition Science and Policy at Tufts University, ‘they will, essentially, be choosing foods based on quality.’
You can make a perfect diet plan with nutrient-dense food. A diet based on the concept of nutrient density will help you lose weight and get all the nutrients your body needs for health.
1. Baker SM. Detoxification & Healing. Keats, 1998.