In recent years, researchers have been working to pin down the mechanics of how fasting affects the brain, using lab mice given treadmill exercises during a fasting regimen:. In lab animals, fasting, as well as exercise, stimulates the production of a protein in nerve cells called brain-derived neurotrophic factor, or BDNF.
This protein plays critical roles in learning, memory, and the generation of new nerve cells in the hippocampus. BDNF also makes neurons more resistant to stress. Fasting also triggers a process called autophagy, where cells remove damaged molecules and dysfunctional mitochondria, and turns off cell growth.
But could fasting just add to the stress in our lives? A writer and researcher on fasting asks us to distinguish between types of stress:. First we have to talk about how stress can be both bad and good. So under good stress, your brain increases the production of certain molecules, such as glucocorticoids, catecholamines, and glucose levels, which prepare your tissues for responsiveness to challenges or danger.
One of the effects of this stress response is sharpened senses and heightened awareness. There is reason to believe that fasting can provide some protection against serious late-life health disorders, cognitive disorders, including Alzheimer syndrome, says a diet specialist:. Certainly fasting may have significant benefits in reducing weight, type 2 diabetes along with its complications — eye damage, kidney disease, nerve damage, heart attacks, strokes, cancer.
The method of protection may also have to do with autophagy — a cellular self cleansing process that may help removed damaged proteins from the body and brain. Since AD may result from the abnormal accumulation of Tau protein or amyloid protein, fasting may provide a unique opportunity to rid the body of these abnormal proteins.
But what happens to your brain when you forgo food? Mark Mattson , a neuroscientist at the National Institute on Aging and a professor at Johns Hopkins University, reveals the surprising brain benefits of fasting. The way we as scientists who study fasting define it is not consuming food for a long enough period of time to elevate the levels of compounds called ketones. This metabolic switch — going from using glucose to using ketones as an energy source — happens after about 10 to 14 hours of not consuming food, depending on how active you are.
Exercise will accelerate the onset of the switch. There are different types of fasting regimens. In lab animals, the main regimen we use is alternate-day fasting where the rats or mice have no food for a hour period, followed by a hour period where they can eat, and so on. In the case of the brain, cognitive function, learning, memory, and alertness are all increased by fasting.
And in the body, we recently found that mice maintained on an alternate-day fasting diet during a month of treadmill training have better endurance than mice fed every day. In lab animals, fasting, as well as exercise, stimulates the production of a protein in nerve cells called brain-derived neurotrophic factor, or BDNF. This protein plays critical roles in learning, memory, and the generation of new nerve cells in the hippocampus.
BDNF also makes neurons more resistant to stress. Fasting also triggers a process called autophagy, where cells remove damaged molecules and dysfunctional mitochondria , and turns off cell growth. Plus it lowers your blood sugar, reduces your insulin levels, and helps you lose weight by reducing total calories. Consider our prehistoric ancestors, the hunters and gatherers who survived through feast and famine, abundance and scarcity.
Many were the days and weeks they failed to catch an auroch or boar and went to sleep hungry. But with the hunger pangs come benefits. Evolution designed our bodies and brains to perform at their peak as hybrid vehicles. Metabolic switching between glucose and ketones is when cognition is best and degenerative diseases are kept at bay.
So how do you do it? Not by overloading on glucose or ketones [the energy source produced when the liver burns fat], but by altering the cadence of eating and letting the body do what it was designed to do during times of food scarcity.
People who follow a serious caloric restriction diet, eating as little as a thousand calories per day, are always hungry. The exhaust from this, ketones, will not only keep your brain going during those periods of fasting and hunger but will actually improve cognition, grow the connections between neurons, and stave off neurodegeneration.
0コメント