For this reason, the first meaningful report on the efficacy of carbohydrate restriction for weight loss was one published in 1936, by Per Hanssen of the Steno Memorial Hospital in Copenhagen. Hanssen reported treating twenty-one obese patients over two years with an 1,850-calorie diet that contained only 450 calories of carbohydrates, or a little less than 25 percent. Nearly 60 percent of the calories came from fat: 65 grams of cream, 65 grams of butter, and 25 grams of olive oil every day, along with two eggs, cheese, and a liberal portion of meat or fish. Some of his patients, Hanssen reported, were so fat initially that they “could scarcely move when they arrived at the hospital, and were unable to work.” On the diet from one to four months, the patients lost an average of two pounds a week. “During the stay in the hospital the patients never felt hungry,” he reported. “The fatigue, a prominent and disturbing symptom, improved often very rapidly, and before the occurrence of any considerable reduction in weight.” Hanssen compared his results with those reported five years earlier by physicians at the nearby University Clinic using a diet consisting of half the calories but twice the proportion of carbohydrates (over 50 percent). “At Steno Memorial Hospital,” Hanssen noted, “a diet of 1,850 calories will reduce weight as quickly as a diet of 950 calories at the University Clinic of Copenhagen.”

If obese individuals can lose weight and keep it off, without hunger, on a diet of 1,850 calories, it’s a reasonable assumption that they will find it easier to sustain such a diet than one that allows only 950 calories, or even less, and assumes, as Evans put it, that the obese “should be hungry most of the time as this is normal.” A diet “relatively poor in carbohydrates,” Hanssen suggested, might “not be so difficult to adhere to as the diets commonly used.”

What additionally complicates any assessment of the role of carbohydrate restriction in reducing diets is that the composition of a diet is never quite so simple as merely being high or low in carbohydrates or refined carbohydrates. Proteins, fats, and calories assume different roles depending on the diet. Also, carbohydrates in these diets can be restricted, but the standard thinking is that they have to remain sufficiently high so that the brain and central nervous system derive all their necessary fuel from this dietary source of glucose. Nutritionists will often insist that 130 grams a day of carbohydrates are the minimal safe amount in a human diet.