How Fasting Improves Your Brain

Intermittent fasting has become popular lately in health and fitness circles, but it’s generally talked about as a way to lose weight or otherwise achieve results focused on the appearance of the body. What’s often lost in these conversations is actually one of the most profound benefits of intermittent fasting: improved brain function.

Your brain is the most metabolically demanding part of your body. One cubic centimeter of brain tissue requires ten times as much energy as one cubic centimeter of muscle. That means that when your metabolic fitness starts to slip, the brain is one of the first organs to suffer. But, conversely, it also means that as your metabolic health improves, your brain is quick to see improvements, too. That’s exactly what happens when fasting.

In this article, we’ll run through the various ways that fasting can benefit your brain, from the moment you start doing it to when it transforms into a long-term habit.

Short Term Benefits of Fasting

As quickly as your first fast, your brain will start to see some of the advantages of fasting. You may start to notice that you feel sharper, maybe clearing some brain fog that you didn’t even know you were carrying around. This is because when you’ve gone without food for a few hours, your body starts to release a chemical called orexin. 

Orexin, also known as hypocretin, is a neuropeptide that regulates arousal, wakefulness, and appetite. One of the many things orexin does is make you more alert and vigilant. This helps you to maintain purposeful activities and motivated behaviors. To put it simply, higher orexin levels support your ability to do things like work, focus, and get stuff done.

Medium Term Benefits of Fasting

When you practice intermittent fasting for a period of weeks or months, you’ll start to notice a new type of benefit: improved mood coming from better hormone and monoamine signaling. This is because fasting results in increased activation of hypothalamic monoamine oxidase (MAO). MOA is an enzyme with a number of important roles throughout the body, including helping to regulate communication between neurons.

One of MOA’s most most important functions is to inactivate monoamine neurotransmitters, including dopamine, norepinephrine, and serotonin. You may recognize these as the names of neurotransmitters that play a big role in mood and motivation; when out of balance, these neurotransmitters are linked to many types of mental illness, including psychiatric and neurological disorders such as depression, anxiety, schizophrenia, and Parkinson’s disease.

In fact, one of the main types of drugs used to treat depression are monoamine oxidase inhibitors (MAOIs). These work by inhibiting monoamine oxidase, elevating mood by allowing monoamine neurotransmitters to stick around just a little longer and increase effect. 

Because fasting decreases the activity of MAO, it can almost be thought to serve as a natural antidepressant; functioning similarly to how MAOIs do by allowing your body to maximize  the “feel good” impact of dopamine and serotonin.

Long Term Benefits of Fasting

One of the most exciting advantages of fasting is one that comes in the long term, compounding over years of metabolic fitness. Essentially, fasting helps to keep your brain clean by encouraging neural autophagy, or the natural, regulated mechanism of the brain cells that removes unnecessary or dysfunctional components, AKA clearing out the junk. This is a vital process and when it doesn’t work properly, the result can be various neural diseases such as Alzheimer’s, Parkinson’s, and Huntington’s disease. In this way, fasting can potentially protect you from neurological disorders, including those we sometimes think of as inevitable consequences of aging.

Additionally, intermittent fasting results in increased production of brain-derived neurotrophic factor (BDNF). BDNF is a critical protein for the long term survival of neurons and underlies the continued growth of new neurons throughout our lives. This means BDNF plays an especially large role in maintaining the parts of the brain responsible for memory and learning. Essentially, fasting can increase the resistance of brain cells to dysfunction and degeneration. This means that your brain will stay healthier for longer, continuing to function properly as you age.

While the research still hasn’t reached the point of supporting fasting as a medical intervention for neurological diseases, it certainly does suggest that it may be a valid prevention strategy.

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The Bottom Line

There are many things that may initially attract somebody to looking into or trying fasting, including aesthetic, religious, or ceremonial reasons. But if fasting is something you are curious about, it’s important to know that it serves you in more ways than just helping you achieve a slim figure. From helping you feel more focused and alert to improving your mood to promoting brain health, fasting proves to be a practice with multiple positive outcomes well worth considering trying out.

No matter what age you are, fasting can help you keep your brain sharper and healthier. We’re here to make getting started with your fasting practice as easy as possible, and help build it into an effortless habit.

Interested in trying intermittent fasting but not sure where to start? Check out our fasting style quiz to find a style of intermittent fasting that works for you.