Neuroscientist Shows What Fasting Does To Your Brain & Why Big Pharma Won’t Study It!
Below is a TEDx talk given by Mark Mattson, the current Chief of the Laboratory of Neuroscience at the National Institute on Aging. He is also a professor of Neuroscience at The Johns Hopkins University, and one of the foremost researchers of the cellular and molecular mechanisms underlying multiple neurodegenerative disorders, like Parkinson’s and Alzheimer’s disease.
I’d like to address the Big Pharma issue first, since there have been countless examples of research manipulation at the hands of pharmaceutical companies in recent years. This is why Harvard Professor of Medicine Arnold Symour Relman told the world that the medical profession has been bought by the pharmaceutical industry. It’s why Dr. Richard Horton, Editor in Chief of The Lancet, recently stated that much of the sceintific literature published today is false. It’s why Dr. Marcia Angell, former Editor in Chief of The New England Journal of Medicine, said that the “pharmaceutical industry likes to depict itself as a research-based industry, as the source of innovative drugs. Nothing could be further from the truth.” And it’s why John Ioannidis, an epidemiologist at the Stanford University School of Medicine, published an article titled “Why Most Published Research Findings Are False,” which subsequently became the most widely accessed article in the history of the Public Library of Science (PLoS).
Dr. Mattson also addresses this issue toward the end of his video:
Why is it that the normal diet is three meals a day plus snacks? It isn’t that it’s the healthiest eating pattern, now that’s my opinion but I think there is a lot of evidence to support that. There are a lot of pressures to have that eating pattern, there’s a lot of money involved. The food industry — are they going to make money from skipping breakfast like I did today? No, they’re going to lose money. If people fast, the food industry loses money. What about the pharmaceutical industries? What if people do some intermittent fasting, exercise periodically and are very healthy, is the pharmaceutical industry going to make any money on healthy people?
Mark and his team have published several papers that discuss how fasting twice a week could significantly lower the risk of developing both Parkinson’s and Alzheimer’s disease.
“Dietary changes have long been known to have an effect on the brain. Children who suffer from epileptic seizures have fewer of them when placed on caloric restriction or fasts. It is believed that fasting helps kick-start protective measures that help counteract the overexcited signals that epileptic brains often exhibit. (Some children with epilepsy have also benefited from a specific high-fat, low-carbohydrate diet.) Normal brains, when overfed, can experience another kind of uncontrolled excitation, impairing the brain’s function, Mattson and another researcher reported in January in the journal Nature Reviews Neuroscience.” (source)
Basically, when you take a look at caloric restriction studies, many of them show a prolonged lifespan as well as an increased ability to fight chronic disease. According to a review of fasting literature conducted in 2003, “Calorie restriction (CR) extends life span and retards age-related chronic diseases in a variety of species, including rats, mice, fish, flies, worms, and yeast. The mechanism or mechanisms through which this occurs are unclear.” The work presented below, however, is now showing some of these mechanisms that were previously unclear.
Fasting does good things for the brain, and this is evident by all of the beneficial neurochemical changes that happen in the brain when we fast. It improves cognitive function and stress resistance, increases neurotrophic factors, and reduces inflammation.
Fasting is a challenge to your brain, and your brain responds to that challenge by adapting stress response pathways that help your brain cope with stress and disease risk. The same changes that occur in the brain during fasting mimic the changes that occur with regular exercise — both increase the production of protein in the brain (neurotrophic factors), which in turn promotes the growth of neurons, the connection between neurons, and the strength of synapses.
As he explains in the video, “Challenges to your brain, whether it’s intermittent fasting [or] vigorous exercise . . . is cognitive challenges. When this happens neuro-circuits are activated, levels of neurotrophic factors increase, that promotes the growth of neurons [and] the formation and strengthening of synapses.”
Fasting can also stimulate the production of new nerve cells from stem cells in the hippocampus. He also mentions how fasting stimulates the production of ketones, an energy source for neurons, and that it may also increase the number of mitochondria in neurons. Fasting also increases the number of mitochondria in nerve cells, since neurons adapt to the stress of fasting by producing more mitochondria.
By increasing the number of mitochondria in the neurons, the ability for nerons to form and maintain the connections between each other also increases, thereby improving learning and memory ability.
“Intermittent fasting enhances the ability of nerve cells to repair DNA.”
He also goes into the evolutionary aspect of this theory, explaining how our ancestors adapted and were built for going long periods of time without food.
A study published in the June 5 issue of Cell Stem Cell by researchers from the University of Southern California showed that cycles of prolonged fasting protect against immune system damage and, moreover, induce immune system regeneration. They concluded that fasting shifts stem cells from a dormant state to a state of self-renewal, triggering stem cell based regeneration of an organ or system (source).
Human clinical trials were conducted using patients who were receiving chemotherapy. For long periods of time, patients did not eat, which significantly lowered their white blood cell counts. In mice, fasting cycles ‘flipped a regenerative switch,’ changing the signalling pathways for hematopoietic stem cells, which are responsible for the generation of blood and immune systems.”
This means that fasting kills off old and damaged immune cells, and when the body rebounds, it uses stem cells to create brand new, completely healthy cells.
“We could not predict that prolonged fasting would have such a remarkable effect in promoting stem cell-based regeneration of the heatopoietic system. . . . When you starve, the system tries to save energy, and one of the things it can do to save energy is to recycle a lot of the immune cells that are not needed, especially those that may be damaged. What we started noticing in both our human work and animal work is that the white blood cell count goes down with prolonged fasting. Then when you re-feed, the blood cells come back. ”
– Valter Longo, corresponding author (source)
A scientific review of multiple scientific studies regarding fasting was published in The American Journal of Clinical Nutrition in 2007. It examined a multitude of both human and animal studies and determined that fasting is an effective way to reduce the risk of cardiovascular disease and cancer. It also showed significant potential in treating diabetes. (source)
Before You Fast
Before you fast, make sure you do your research. Personally, I’ve been fasting for years, so it is something that comes easy for me.
One recommended way of doing it, which was tested by the BBC’s Michael Mosley in order to reverse his diabetes, high cholesterol, and other problems associated with his obesity, is what is known as the “5:2 Diet.” On the 5:2 plan, you cut your food down to one-fourth of your normal daily calories on fasting days (about 600 calories for men and about 500 for women), while consuming plenty of water and tea. On the other five days of the week, you can eat normally.
Another way to do it, as mentioned above, is to restrict your food intake between the hours of 11am and 7pm daily, while not eating during the hours outside of that time.
Ultimately, a proper diet remains critical to good health, and how you think about what you are putting in your body is an important piece of that puzzle, which I believe will eventually be established in the unbiased and uninfluenced medical literature of the future.
Below is a video of Dr. Joseph Mercola explaining the benefits of intermittent fasting, and here is a great article by him that explains how he believes intermittent fasting can help you live a healthier life.
In the featured documentary, Eat, Fast, and Live Longer,1 British author and journalist Dr. Michael Mosley documents his journey as he decides to try fasting, to see if it might improve his health.
At the outset, his blood work revealed he was borderline diabetic and his cholesterol was high, which his doctor wanted to treat with medication.
Concerned by this diagnosis—especially as he considers himself somewhat of an expert on conventional health strategies—Dr. Mosley sets out to investigate his alternatives.
“I have always been interested in self-experimentation as a research device because so many of the most important discoveries came from scientists and doctors who used themselves as test subjects,” he says, “but I had never before performed a series of trials on my own health.”
His journey takes him across the United States, where he meets with both long-lived, healthy folk, and health and longevity experts, to learn the secrets of their success.
Your Body Was Built for Periodic Cycles of ‘Feast and Famine’
Fasting, it turns out, has a number of health benefits that most people seek: from improved cardiovascular health and reduced cancer risk, to gene repair and longevity.
In short, he discovers that part of what appears to be driving the disease process is the fact that we’re eating too frequently. When you’re in constant “feast mode,” your body actually forgoes much of its natural “repair and rejuvenation programming.”
It’s true that severe calorie restriction promotes both weight loss and longevity in animal models, but this kind of “starvation diet” is not a very appealing strategy for most people.
However, newer research shows that you can get most if not all of the same benefits of severe calorie restriction through intermittent fasting, i.e. an eating schedule where you feast on some days, and dramatically cut calories on others.
This effectively mimics the eating habits of our ancestors, who did not have access to grocery stores or food around the clock. They would cycle through periods of feast and famine, and modern research shows this cycling produces a number of biochemical benefits. In short, by altering what and when you eat, you can rather dramatically alter how your body operates. And that’s great news.
Health Benefits of Intermittent Fasting
Fasting is historically commonplace as it has been a part of spiritual practice for millennia. But modern science has confirmed there are many good reasons for fasting, including the following:
Normalizing your insulin and leptin sensitivity, and boosting mitochondrial energy efficiency: One of the primary mechanisms that makes intermittent fasting so beneficial for health is related to its impact on your insulin sensitivity.
While sugar is a source of energy for your body, it also promotes insulin resistance when consumed in the amounts found in our modern processed junk food diets. Insulin resistance, in turn, is a primary driver of chronic disease—from heart disease to cancer.
Intermittent fasting helps reset your body to use fat as its primary fuel, and mounting evidence confirms that when your body becomes adapted to burning FAT instead of sugar as its primary fuel, you dramatically reduce your risk of chronic disease
Normalizing ghrelin levels, also known as “the hunger hormone”
Promoting human growth hormone (HGH) production: Research has shown fasting can raise HGH by as much as 1,300 percent in women, and 2,000 percent in men,2 which plays an important part in health, fitness, and slowing the aging process. HGH is also a fat-burning hormone, which helps explain why fasting is so effective for weight loss
Lowering triglyceride levels and improving other biomarkers of disease
Reducing oxidative stress: Fasting decreases the accumulation of oxidative radicals in the cell, and thereby prevents oxidative damage to cellular proteins, lipids, and nucleic acids associated with aging and disease
There’s also plenty of research showing that fasting has a beneficial impact on longevity in animals. There are a number of mechanisms contributing to this effect. Normalizing insulin sensitivity is a major one, but fasting also inhibits the mTOR pathway, which plays an important part in driving the aging process.
Intermittent fasting is by far the most effective way I know of to shed unwanted fat and eliminate your sugar cravings. Since most of us are carrying excess fat we just can’t seem to burn, this is a really important benefit. When sugar is not needed as a primary fuel, your body will also not crave it as much when your sugar stores run low.
As mentioned above, the other mechanisms that makes fasting so effective for weight loss is the fact that it provokes the secretion of HGH—a fat-burning hormone that has many well-recognized “anti-aging” health and fitness benefits.
Last but not least, intermittent fasting has also been identified as a potent ally for the prevention and perhaps even treatment of dementia. First, ketones are released as a byproduct of burning fat, and ketones (not glucose) are actually the preferred fuel for your brain.
In addition to that, intermittent fasting boosts production of a protein called brain-derived neurotrophic factor (BDNF), which activates brain stem cells to convert into new neurons, and triggers numerous other chemicals that promote neural health. It also protects your brain cells from changes associated with Alzheimer’s and Parkinson’s disease. Research by Dr. Mark Mattson, a senior investigator for the National Institute on Aging, suggests that alternate-day fasting (restricting your meal on fasting days to about 600 calories), can boost BDNF by anywhere from 50 to 400 percent, depending on the brain region.3
The 5:2 Intermittent Fasting Plan
Intermittent fasting is an umbrella term that covers a wide array of fasting schedules. As a general rule, it involves cutting calories in whole or in part, either a couple of days a week, every other day, or even daily. Dr. Mosley became so convinced of the health benefits of intermittent fasting he wrote a book on the subject, called The Fast Diet: Lose Weight, Stay Healthy, and Live Longer with the Simple Secret of Intermittent Fasting.4
The fasting schedule he ultimately suggests in the book (after trying a couple of variations in the film), is to eat normally for five days a week, and fast for two. This schedule is sometimes referred to as the “5:2” intermittent fasting plan. On fasting days, he recommends cutting your food down to one-fourth of your normal daily calories, or about 600 calories for men and about 500 for women, along with plenty of water and tea. Dr. Mosley claims to have lost 19 pounds in two months by following this 5:2 intermittent fasting plan.
Alternate-Day Fasting—Another Alternative
Yet another variation that is quite common is the alternate-day fast. This fasting protocol is exactly as it sounds: one day off, one day on. When you include sleeping time, the fast can end up being as long as 32-36 hours. The drawback is that it requires you to go to bed with an empty stomach every other day, which can be tough for most people—at least initially.
However, according to Dr. Krista Varady, author of The Every-Other-Day Diet: The Diet That Lets You Eat All You Want (Half the Time) and Keep the Weight Off, the alternate-day fasting schedule does have a much higher compliance rate than many other fasting schedules. In the end, the best fasting schedule is the one that you will comply with. If you’re constantly cheating, it won’t work.
Dr. Varady’s research shows that alternate-day fasting, where you consume about 500 calories on fasting days and can eat whatever you want on non-fasting days, works equally well for weight loss as complete fasting, and it’s a lot easier to maintain this type of modified fasting regimen.
In her study, which was recently completed, participants ate their low-calorie fasting day meal either for lunch or dinner. Splitting the 500 calorie meal up into multiple smaller meals throughout the day was not as successful as eating just one meal, once a day. The main problem relates to compliance. If you’re truly eating just 500 calories in a day, you will lose weight. But when eating tiny amounts of food multiple times a day, you’re far more inclined to want more, so the cheat rate dramatically increases.
My Personal Recommendation
A third version of intermittent fasting, and the one I recommend and personally use, is to simply restrict your daily eating to a specific window of time, such as an eight hour window. I have experimented with different types of scheduled eating for the past three years, and this is my personal preference as it’s really easy to comply with once your body has shifted over from burning sugar to burning fat as its primary fuel.
Fat, being a slow-burning fuel, allows you to keep going without suffering from the dramatic energy crashes associated with sugar. And, if you’re not hungry… well, then not eating for several hours is no big deal! You do this every day until your insulin/leptin resistance improves (weight, blood pressure, cholesterol ratios, or diabetes normalizes). Then you continue to do it as often as you need to maintain your healthy state. I used a six hour window until I was burning fat for fuel, and now eat in a 9-10 hour window, and will snack on macadamia nuts during that period. I rarely eat anything for four or more hours before going to bed.
Compliance is always a critical factor in any of these approaches and it seems this is one of the easiest intermittent fasting schedules to implement. It really is beyond amazing to me how the food cravings literally disappear once you have regained your ability to burn fat for fuel. You don’t need iron willpower or enormous levels of self-discipline to maintain this eating schedule. Yes, you will get hungry, but your hunger will be appropriate and you will be surprised at how much less food will completely satisfy you once you regain your metabolic flexibility and no longer need to rely on stored sugar in your body for your primary fuel.
What Should You Eat on Non-Fasting Days?
In the featured documentary, Dr. Krista Varady takes Dr. Mosley out for lunch at a local fast food restaurant, noting that it doesn’t seem to matter what you eat on your non-fasting day, as long as you’re fasting properly every other day. I would caution against versions of intermittent fasting that gives you free reign to eat all the junk food you want when not fasting, as this seems awfully counterproductive. From my perspective, I simply cannot agree with or promote this idea.
I view intermittent fasting as a lifestyle, not a diet, and that means making healthy food choices every time you eat. Your goal is to seek to emulate the eating patterns of your ancient ancestors, which was a constant feast and famine pattern. Besides, if alternating between feasting on junk food and fasting can produce favorable metabolic results as in the video, just imagine the health benefits you’d get if you were actually making healthy food choices each time you ate!
Unfortunately, Dr. Varady doesn’t appreciate the dangers of processed foods and trans fats in particular. She focuses mostly on the quantity, not the quality, of the calories. A healthy diet includes minimizing non-starchy, carb-rich processed foods and replacing them with healthy fats like coconut oil, olive oil, olives, butter, eggs, avocados, and nuts (macadamia are particularly beneficial, as they are high in fat and low in protein). I also recommend being moderate in your protein consumption, and making sure meat and other animal products like dairy and eggs come from organic, pasture-raised animals.
I would also caution against eating enormous amounts of fruit, like Joe Cordelli, the calorie restricter at the beginning of the film. He starts out his day with a supersized bowl of fruit, and even though he tosses out certain parts that are particularly high in fructose, I believe most people would be wise to refrain from excessively large amounts of fruit—at least until your weight and health has normalized. While a fruit-rich diet may work for some people, in the end you need to pay close attention to your metabolic parameters, and getting your vitamins and antioxidants from vegetables would be a more appropriate strategy for most.
Speaking of sugar, if you have a sweet tooth, don’t despair. It typically takes several weeks to shift to burning fat as your primary fuel, but once you do, your cravings for unhealthy foods and carbs will automatically disappear. Again, this is because you’re now actually able to burn your stored fat and don’t have to rely on new fast-burning carbs for fuel. Once you are at your ideal body weight, and do not have diabetes, high blood pressure, or abnormal cholesterol levels, you can be less rigid with your fasting. However, it is probably best to resume some type of scheduled eating regimen once in a while, to make sure you don’t slip back into old habits.
Who Should Use Extra Caution When Fasting, or Avoid It Altogether?
Intermittent fasting is appropriate for most people, but if you’re hypoglycemic or diabetic, you need to be extra cautious. People that would be best served to avoid fasting include those living with chronic stress (adrenal fatigue), and those with cortisol dysregulation. Pregnant or nursing mothers should also avoid fasting. Your baby needs plenty of nutrients, during and after birth, and there’s no research supporting fasting during this important time.
My recommendation would be to really focus on improving your nutrition instead. A diet with plenty of raw organic foods and foods high in healthy fats, coupled with high-quality proteins, will give your baby a head start on good health. You’ll also want to be sure to include plenty of cultured and fermented foods to optimize your—and consequently your baby’s—gut flora. For more information, please see this previous article that includes specific dietary recommendations for a healthy pregnancy, as well as my interview with Dr. Natasha Campbell-McBride.
Hypoglycemia is a condition characterized by an abnormally low level of blood sugar. It’s commonly associated with diabetes, but you can be hypoglycemic even if you’re not diabetic. Common symptoms of a hypoglycemic crash include headache, weakness, tremors, irritability, and hunger. As your blood glucose levels continue to plummet, more severe symptoms can set in, such as:
Confusion and/or abnormal behavior
Visual disturbances, such as double vision and blurred vision
Loss of consciousness
One of the keys to eliminating hypoglycemia is to eliminate sugars, especially fructose from your diet. It will also be helpful to eliminate grains, and replace them with higher amounts of quality proteins and healthy fats. You can use coconut oil to solve some of these issues as it is a rapidly metabolized fat that can substitute for sugar, and since it does not require insulin, it can be used during your fast. However, it will take some time for your blood sugar to normalize. You’ll want to pay careful attention to hypoglycemic signs and symptoms, and if you suspect that you’re crashing, make sure to eat something, like coconut oil. Ideally, you should avoid fasting if you’re hypoglycemic, and work on your overall diet to normalize your blood sugar levels first. Then try out one of the less rigid versions of fasting.