For more than a century, fasting has been used as a weight loss treatment.
I have speak about the benefits of calorie restriction. Well, the biggest calorie restriction is not consuming any calories. Fasting has been brand “the next big weight loss fad,” but it has a long history throughout various spiritual traditions, expert by Moses, Jesus, Muhammad and Buddha. In 1732, a prominent doctor wrote, “He who eats until he is sick, must fast until he is healthy.” About one in seven American adults today report following that advice, “using fasting as a means to control body weight”, as I explain in my video Benefits of fasting for weight loss put to the test.
Case reports of the treatment of obesity by fasting. date more than a century ago in medical literature. In 1915, two Harvard doctors indelicately described “two extraordinarily fat women,” one of whom “was a real pig.” Their success led them to conclude that “successive moderate periods of starvation constitute a perfectly safe, harmless and effective method of reducing the weight of those suffering from obesity.”
The longest fast on record, published in 1973, reached Guinness Book of World Records. To achieve his ideal body weight, a 27-year-old man on an empty stomach For 382 days in a row, he lost 276 pounds and managed to keep it off almost all of it. He was given vitamin and mineral supplements so he wouldn’t die, but no calories for over a year. In the researchers’ acknowledgments, they thanked him for “his cheerful cooperation and his firm application to the task of achieving a normal physique.”
In a U.S. Air Force study, more than 20 people at least 100 pounds overweight and most “unable to lose weight with previous diets” were fasting for up to 84 days. Nine dropped out of the study, but the 16 who remained “were unequivocally successful” in losing between 40 and 100 pounds. In the first four days, subjects were observed losing up to four pounds per day, which “probably represents primarily liquid weight,” mostly water, as the body begins to adapt. But, after a few weeks, they were steadily losing about a pound a day of mostly pure fat. The researcher described the anti-hunger program as “a spectacular and exciting treatment for obesity.”
Of course, the most successful diet for weight loss (i.e. no diet) is also the least sustainable. What other diet can cure morbid obesity in a matter of months but practically guarantees death within a year if you follow it? The reason diets don’t work, almost by definition, is that people go on them and then quit. Permanent weight loss is only achieved through a permanent lifestyle change. So what’s the point of fasting if you’re just going to go back to your regular diet and regain all the weight you lost?
Advocates of fasting quote the psychological benefit of realigning people’s perceptions and motivation. Some people have resigned themselves to the belief that losing weight is somehow impossible for them. Which can think “who are ‘built differently’ than normal weight people” in some way, and no matter what they do, the pounds don’t go away. But the rapid and unequivocal weight loss during fasting shows them that with a sufficiently large change in eating habits, this is not only possible, but inevitable. This moral impulse can then embolden to make better food choices once they eat again.
The meal break can allow for some, the opportunity to “pause and reflect” on the role food plays in their lives: not just the power it has over them, but the power they have over it. In a fasting study entitled In “Correction and Control of Intractable Obesity,” a patient’s personality was described as changing “from a personality of despair, with abandonment of hope, to that of an anxious extrovert full of plans for a promising future.” He realized that he could control his weight. The researchers concluded: “This highly intellectual social worker has regained a full degree of exceptional usefulness.”
After a fast, the new commitment to healthier eating can be facilitated by a reduction in overall appetite reported after fasting, compared to before fasting, at least temporarily. Even during a fast, hunger can begin to subside. dispel within the first 36 hours. So, challenging People’s delusions about being exceptional from the laws of physics (thinking they are “made differently”) with “short periods of total fasting” may seem barbaric. “In fact, this method of weight reduction is remarkably well tolerated by obese patients.” This appears to be a recurring theme in this series of published cases. In the influential article “Treatment of obesity by total fasting for up to 249 days,” researchers commented that “the most surprising aspect of this study was the ease with which prolonged fasting was tolerated.” All of his patients “commented spontaneously on their increased sense of well-being and, in some, this amounted to downright euphoria.” They went on to say that, although “treatment by total fasting should only be prescribed under close medical supervision,” “they are convinced that it is the treatment of choice, especially in cases of severe obesity.”
Fasting for a day can do irritable people and feel moody and distracted, but after a few days of fasting, many report feeling clear, euphoric and alert, even euphoric. This may be due in part to the significant increase in endorphins that accompanies fasting, as you can see in the graph below and at 5:48 in my video. Improved mood during fasting is thought perhaps representing an adaptive survival mechanism to motivate foraging. This positive outlook toward the future can facilitate the behavioral change necessary to secure some of the benefits of weight loss.
But is that what happens? Is long-term fasting really effective? There are articles with titles like “Death during therapeutic starvation for obesity.” Is fasting even safe? We will find out below.
This is the sixth in a 14-part series on fasting for weight loss. In case you missed any of the others, check out the related videos below.
My book How not to diet It’s about losing weight. You can learn more about it and order it here.