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More on Fasting

Caloric restriction has its charms for many people. It also has a dizzying array of side effects.

This episode features audio from Fasting to Reverse Diabetes, Fasting to Treat Depression, and Fasting for Post-Traumatic Brain Injury Headache. Visit the video pages for all sources and doctor’s notes related to this podcast.


There is a lot of demand for information about fasting. And – as luck would have it – more and more research is released every day. Today, we look at the practice of fasting to reverse type 2 diabetes. 

Currently, nearly half a billion adults have diabetes, and a 50 percent increase is expected in another generation. I’ve got tons of videos on the best diets for diabetes, but what about no diet at all?

More than a century ago, fasting was said to bring about the cure of diabetes, speedily arresting its development, and causing complete disappearance of all its manifestations in several days or weeks. Even so, starvation is guaranteed to lead to the complete disappearance of you, if kept up long enough. What’s the point of fasting it away if it’s just going to come raging back as soon as you restart the diet that caused it in the first place? Might it be useful to kind of kickstart a healthier diet? Let’s see what the science says.

Type 2 diabetes has long been recognized as a disease of excess, a disease of the idle rich, by which they mean anyone that doesn’t practice sustained vigorous bodily exertion every day, and earning enough to regularly eat more than they need, so diabetes is preventable, but then maybe it’s also treatable. If we are dying of overeating, maybe we can be saved by undereating. Remarkably, this was suggested about 2,000 years ago in an Ayurvedic text. Diabetics were encouraged to live like a saint, walk for oh, 800 to 900 miles, dig a pond, or live only on cow dung and cow urine.

That reminds me of the Rollo Diet for diabetes proposed in 1797, composed of a diet of rancid meat. That was on top of the ipecac-like drugs he used to produce severe sickness and vomiting. Anything that produces sickness has a temporary effect in relieving diabetes by diminishing the quantity of food eaten—and his diet plan, congealed blood for lunch and spoiled meat for dinner, certainly had that effect.

Similar benefits were seen in diabetics during the siege of Paris in the Franco‐Prussian War, leading to the advice to “Mangez le moins possible;” eat as little as possible. This was formalized into the Allen Starvation Treatment, considered to be the greatest medical advance in the treatment of diabetes prior to the discovery of insulin. Before insulin, there was The Allen Era

He noted reports in the clinical literature of even severe diabetes clearing up on wasting diseases like tuberculosis; so, he decided to put it to the test. He found that even in the most severe type of diabetes, he could clear sugar from people’s urine within 10 days. Of course, that’s the easy part—it’s maintaining it once you start eating again, for which he stuck to two principles: keeping them underweight, and restricting the quantity of fat. A severe diabetic can be symptom-free for days or weeks, but add some butter or olive oil, and the disease can come raging back.

As I’ve covered before, diabetes is a disease of fat toxicity. Infuse fat into people’s veins through an IV, and, by using a high-tech type of MRI scanner, you can show in real time the buildup of fat in muscle cells within hours, accompanied by an increase in insulin resistance. The same thing happens when you put people on a high-fat diet for three days, or even just one day…or even just a single meal can increase insulin resistance within six hours. Acute dietary fat intake rapidly increases insulin resistance. Why do we care? Because insulin resistance in our muscles in the context of too many calories leads to a buildup of liver fat, which leads to the buildup of fat in the pancreas, which is eventually what causes diabetes. Type 2 diabetes can now be understood as a state of excess fat in the liver and pancreas, and remains reversible for at least 10 years in most individuals.

Put people on a very low-calorie diet, 700 calories a day, and fat can get sucked out of your muscle cells, and you get a corresponding boost in insulin sensitivity. Fat is then sucked out of your liver, and if you keep it up the fat gets sucked out of your pancreas, and if you catch it early enough, that means a reversal of your type 2 diabetes, meaning normal sugars on a normal diet.

With the loss of 15 percent of body weight, nearly 90 percent of those who’ve had type 2 diabetes for less than four years can achieve remission, whereas it may only be reversible in 50 percent of those who’ve lived with the disease for longer than eight years. That’s better than bariatric surgery, where those losing even more weight only got 62 and 26 percent remissions. Your forks are better than surgeon’s knives. Here’s how much weight you have to lose to achieve various remission rates for those who’ve had diabetes for an average of three years. Lose about 30 pounds, and most newly-diagnosed type 2 diabetics can reverse their disease. So, an extended bout of physician-supervised, water-only fasting could get you there, but you have to maintain that weight loss. One of the things we can say with certainty is that if you regain the weight, you regain your diabetes.

To bring it full circle, the initial euphoria about “medicine’s greatest miracle,” the discovery of insulin in 1921, soon gave way to the realization that while it was literally a life-saver for type 1 diabetics, the use of insulin on its own in type 2 diabetics would not be enough to prevent the later onset of complications like kidney failure, blindness, stroke, amputations; so, as argued by one the most famous diabetes pioneers, Elliot Joslin, self-discipline on diet and exercise, as it was in the days prior to insulin, should be central to the management of diabetes.

Did you know that caloric restriction can boost levels of brain-derived neurotrophic factor – otherwise known as BDNF? In fact, I just wrote a chapter on it in my upcoming book “How Not To Age.” Anyway, here’s the story.

For over a century, fasting has been espoused as a treatment of supposed “great utility in the preservation of health,” especially rejuvenating the body, but above all the mind. But fast people even just 18 hours, and they get all hungry and irritable. After one or two days, positive mood goes down, negative mood goes up, and by 72 hours people can feel sad, self-blaming, and suffer a loss in libido. But then, something strange starts to happen. After a few days, people experience a “fasting-induced mood enhancement…decreased anxiety, depression, fatigue, and improved vigor.” And that’s what studies tend to show across the board. Once you get over the hump, fasters frequently experience “an increased level of vigilance and…mood improvement, a subjective feeling of well-being, and sometimes [even] euphoria.” And no wonder, as by then your endorphin levels may shoot up nearly 50 percent.

This enhancement of mood, alertness, and calm makes a certain amount of evolutionary sense. Yeah, your body wants you to feel crappy initially so you continue eating day to day when food is available, but if you go a couple days without food, your body realizes it can’t have you moping back in the cave—you’ve got to get motivated to get out there and find some calories.

So, can fasting be used for mood disorders like depression? Yeah, it’s great that you can get people to feel better after a few days of fasting, but the critical question revolves around “the persistence of mood improvement over time,” once you start eating again. You don’t know until you put it to the test.

Interestingly, the little published evidence we have comes out of Japan and the former Soviet Union, and some of it is just ridiculous. Ten days of fasting, but they also kept them in bed all day completely isolated, with no contact with the outside world. So, if people got better or worse, it would be impossible to tease out the effects of just the fasting component. But they did apparently get better, with efficacy supposedly demonstrated in 31 out of 36 patients suffering from depression. They conclude that fasting therapy may provide an alternative to the use of antidepressant drugs, considering it “a kind of shock therapy.” People are so relieved to just be eating again, to get out of solitary confinement, to even just get out of bed, they report feeling better. Yeah, but that was at the time of discharge. How did they feel the next day, the next week, the next month? Fasting is by definition unsustainable; so, ideally what we want to see are some kind of longer-lasting effects.

So, what the researchers did was follow-up with a few hundred patients, not just a few months later, but a few years later. Of the 69 who were evidently suffering from depression, 90 percent reported feeling good or excellent results at the end of the 10-day fast, and remarkably, years later, 87 percent of the 62 that replied claimed that they were still doing good. Now, there was no control group; so, we don’t know if they would have done just as well or better without the fast, and it was just self-reports, so maybe there was response bias where you try to please the researchers, or maybe they were afraid otherwise they’d get sent back to the hole. We have no idea, but we do have good evidence for the short-term mood benefits. The question is why.

In addition to the endorphins when you fast and the surge in serotonin––the so-called happiness hormone––there is a bump in BDNF, brain-derived neurotrophic factor, considered to play a crucial role in mood disorders. And it’s not just because you perk up rodents with it. Humans with major depression have lower levels circulating in their bloodstream. Autopsy studies of suicide victims show only about half the BDNF in certain key brain regions compared to controls, suggesting it may play an important role in suicidal behavior.

You can boost BDNF with antidepressant drugs and electroshock, or with calorie restriction—a 70 percent boost in levels after three months cutting 25 percent of calories out of their daily diet.

But is there anything we can add to our diets to boost BDNF levels so we can get the benefits without the hunger? We’ll find out next.

What effect does fasting and a plant-based diet have on Traumatic Brain Injury and migraines?  Let’s find out.

An uncontrolled and unpublished study purported to show a beneficial effect of fasting on migraine headaches, but fasting may be more likely to trigger a migraine than help it. In fact, skipped meals are among one of the most consistently identified dietary triggers of headaches in general. In a review of hundreds of fasts at the TrueNorth Health Center in California, the incidence of headache was nearly one in three. But TrueNorth also published a remarkable case report on posttraumatic headache.

The CDC estimates that more than a million Americans sustain traumatic brain injuries every year, and chronic pain is a common complication, as in like three-quarters suffering such an injury. There are drugs, of course, to treat it. There are always drugs. And if that doesn’t work, surgery—cutting the nerves to your head to stop the pain.

What about fasting and plants? In a highly debilitating condition, difficult to manage, a 52-year-old woman presents with unremitting, chronic post-traumatic headache. And when I say chronic, I mean chronic—pain for 16 years—but who then achieved long-term relief following fasting, followed by an exclusively plant-based diet, free of added sugar, oil, or salt.

Before then, she had tried drug after drug, after drug, after drug, after drug with no relief, suffering in constant pain her entire life. She started out in constant pain, but then, after the fast, the intensity of the pain was cut in half, and though she was still having daily headaches, at least there were some pain-free periods. Six months later, she tried it again, and eventually her headaches were mild, under 10 minutes, and infrequent. And she continued that way months and even years later.

Now, of course, it’s hard to disentangle the effects of the fasting from the effects of the whole food plant-based diet she remained on those ensuing years. You’ve heard of analgesics (painkillers). Well there are some foods that may be pro-algesic (pain-promoting), such as foods high in arachidonic acid, which includes include meats, dairy, and eggs. So, the lowering of arachidonic acid, from which our body makes a range of pro-inflammatory compounds, may be accomplished by eating a more plant-based diet.

So, maybe that contributed to the benefit in the fasting case, whereas many plant foods are high in anti-inflammatory components. So, in terms of migraine headaches, more plant foods and less animal foods may help. But you don’t know until you put it to the test.

The researchers figured a plant-based diet may offer the best of both worlds; so, they designed a randomized, controlled crossover study where those with recurrent migraines were randomized to eat a strictly plant-based diet or to take a placebo pill. And then, the groups switched. During the placebo phase, half said the pain got better; half said the pain remained the same or got worse. But during the dietary portion, they almost all got better.

During that first block, the diet group experienced significant improvements in headache number, pain intensity, days with headaches, and a reduction in the amount of painkillers they needed to take. In fact, it worked a little too good. Many individuals were unwilling to complete the study by returning to their previous diets. Remember, they were supposed to go back to their regular diets and take a pill instead, but they felt so much better they were like, “No way, José.” And we’ve seen this with other trials, where those trying plant-based diets felt so good, they often refused to abandon them, screwing up the study. So, plant-based diets can sometimes work a little too well.

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