Fasting on purpose might not sound like a good idea but going without food for more than a few hours between meals may be the key to safeguarding brain functions over the long term.
Mark Mattson is a professor of neuroscience at John’s Hopkins School of Medicine and has researched the brain extensively. He points out that humans originally evolved to go without food for extended periods of time.
“Individual brains had to function very well in a food-deprived state. Otherwise, they’re not going to be successful in acquiring food,” Mattson says.
Fasting triggers a shift in the resources your body uses for energy. Your metabolism moves from using glucose to ketones to power the body. Ketones are a type of acid produced by the liver from fat – interestingly, ketogenic diets rely on this shift, too.
But it’s not just fat-burning – the increased use of ketones during fasting periods and the switch back to use glucose following eating is known as “metabolic switching”. In turn, this triggers a biological cascade in the body which scientists believe may build the brain’s resilience and productivity and boost its support system.
It is thought cells go into a survival and repair mode during the fasts, followed by growth and regeneration during the refeeding phase.
Evidence suggests four brain health effects linked to fasting:
- Fasting May Help Create More Baby Brain Cells
Ghrelin, the hormone which prompts us to eat, dials up during periods without food. There is evidence to suggest this increase also spurs the creation of new brain cells.
The findings of many studies suggest that fasting-induced boosts in ghrelin play a crucial role in brain health.
Although most of the studies are not on humans, Mattson suspects the same processes might be at play in human brains too, but there isn’t enough evidence so far to know this for sure.
- Fasting May Improve Cognition and Mood
One has only to scan the web to find plentiful, anecdotal evidence of fasting’s head-clearing, intelligence-boosting effects.
In humans, some fasting studies looked specifically at people who fast as part of their religious practice. One study involving 13 people that did control for sleep (sleep schedules) found that, after a week of fasting, participants’ sleep, concentration, and emotional balance improved.
- Fasting Could Help Treat Brain Conditions
Aside from brain diseases associated with old age, fasting could help manage other brain and nervous-system conditions.
Fasting was prescribed as a treatment for people with epilepsy more than 2,000 years ago. The ancient technique is still used today to treat people with the condition, as are ketogenic diets, which echo some of the effects of fasting on the body.
A rat study from 2008 found that just one day of fasting after a serious brain injury helped save brain tissue. In yet another mouse study from 2014, mice on an intermittent fasting diet also showed lower than expected cell death following a stroke.
- Fasting Could Slow A Decline in Brain Function
Intermittent fasting may also be a way to protect against conditions marked by a decline in brain function – like Alzheimer’s, Parkinson’s’, and Huntington’s’ diseases – although the evidence here, too, stems mainly from mouse studies.
The evidence suggests the switch between eating and fasting periods, which acts like a hard reset on the body, may be the key.
There are tentative signs people with Parkinson’s may see some benefits from following a keto diet, including decreased pain, sleepiness, and cognitive impairment.
If the preliminary animal studies hold up in future research done on people, then fasting may significantly affect cognition, alertness, and learning.
That’s it for now; see you all the next time my friends.