Intermittent fasting is a popular nutrition trend now, and I’m getting asked a lot of questions about it. So I want to unpack the science and give you my take on it. And in case you’re wondering: yes, I’ve tried it personally and quite like it but no, it is not part of our standard NeuroTrition Rx (more on why not below).

Basically, people are using Intermittent Fasting (or IF, for short) to lose weight, help reduce high blood pressure, help their asthma, and even manage rheumatoid arthritis. It may also help protect against diabetes, heart disease, and cancer. And it may even help you live longer.

And, of course, there is a neuroscience angle, too.

Intermittent fasting, or IF, may help your brain in a few different ways.

Who would have thought “un-fueling” your brain (just temporarily, though!) can help it stay healthy for longer?

Let’s have a look at what the science is saying about the brain-boosting powers of intermittent fasting — as well as get answers to some of my most frequently asked questions on this topic.

WHAT IS INTERMITTENT FASTING?

IF is not a diet, but rather an eating pattern that involves short periods of fasting. It does not recommend what to eat, but more so when to eat.

IS IT HARD TO DO?

Many people actually find IF easy to follow because eating fewer meals in a shorter time frame can simplify their life. However, if you have blood sugar issues (and most of our clients in the brain and mental health space do!) then IF isn’t for you, until we get you off the blood sugar rollercoaster. Got that? We don’t want any hypoglycemia (i.e. low blood sugar) or subsequent fainting, if you try IF when you have blood sugar issues.

HOW DOES INTERMITTENT FASTING AFFECT YOUR BODY AND BRAIN?

Because of the restricted eating times, IF reduces the amount of calories consumed for short periods of time. Hence the “un-fueling” aspect. This helps drive the body and brain health benefits.

Another effect is that IF helps burn fat. When your body doesn’t get enough calories from food, it uses the calories stored as fat.

Intermittent fasting increases your metabolism, reduces your risk of heart disease, and reduces both oxidation and inflammation.

Fasting also affects your hormones in a way that reduces blood sugar and improves insulin resistance. IF increases your metabolism, reduces your risk of heart disease, and reduces both oxidation and inflammation. Not to mention that (in animal studies, so far) it can also reduce the risk of diabetes, cancer, and even extend lifespan.

If you read NeuroTrition blogs regularly, then you most likely know, reducing oxidation (i.e. free radicals!), reducing inflammation (including that nasty neuro-inflammation), and stabilizing blood sugar levels also benefit your brain.

How exactly does IF help your brain? I thought you’d never ask! Here are the top 5 ways, as supported by the neuroscience research.

TOP 5 WAYS INTERMITTENT FASTING HELPS YOUR BRAIN

1. Intermittent fasting for more brain proteins

One of the main ways IF benefits the brain is by increasing one of my Fave proteins that the brain makes, brain-derived neurotrophic factor (BDNF).

I love BDNF because it is very beneficial to brain cells by being a growth factor. It grows new neurons (nerve/brain cells), allows them to talk to one another, and is a natural antidepressant.

In animal studies, BDNF also helps neurons stay healthier longer and helps them resist common brain diseases (like dementia) and injury (from strokes). All by maintaining proper neuron structure and function.

Way to go, BDNF. Love ya!

2. Intermittent fasting to help grow new nerve cells

Intermittent fasting actually helps to grow new nerve cells.

Fun Factoid: Severe fasting results in a reduction in size in most organs…except for the brain. You already knew your body goes to great lengths to preserve your uber-important noggin, right? (Please note that I’m not talking about “severe fasting” with IF.)

Yes, mammalian brains grow new nerve cells when intermittently fasting!

So, how does more brain hormone and new nerve cells translate into better neuro-health, you ask?

Well, they help with brain aging, brain damage from strokes, and epilepsy.

Here’s how (and I’m so excited for this part!).

3. Intermittent fasting for better brain aging

Intermittent fasting seems to keep our brains staying younger. It may even protect against neurodegeneration (loss of structure and function of neurons) from Alzheimer’s disease, Parkinson’s disease and Huntington’s disease.

One small study, for example, showed that IF improved cognitive ability (ability to think) in people with cognitive impairment. Ten people with early signs of Alzheimer’s started several lifestyle improvements including a 12-hour fast each night. Within 3-6 months, nine of the ten patients had improved cognition.

Preclinical animal studies also show that IF may delay the onset, or reduce severity of Alzheimer’s, Parkinson’s, and Huntington’s diseases.

4. Intermittent fasting to protect against brain damage from strokes

Studies show that animals who get strokes have less brain damage if they’ve been intermittently fasting. They also have more BDNF along with antioxidant and anti-inflammatory brain compounds.

In addition, not only did they have less brain damage, but fewer of them died because of the stroke. I think this is important research because it suggests that IF could possibly protect us against both brain damage and death from having a stroke.

5. Intermittent fasting for epilepsy

Many studies show that when a brain uses less of its main fuel, carbohydrates, as it does in the fasting state (and the ketogenic diet), the number of epileptic seizures reduces.

Interestingly, while both the ketogenic diet and IF seem to reduce seizures, the types of seizures that each reduced were different. More research is needed in this area.

HOW DO I INTERMITTENTLY FAST?

There are a few common ways to intermittently fast and I have personally tested two of the best ways on myself. I quite like IF (but again, I can’t say this enough: if you’re riding that blood sugar roller coaster PLEASE get off it before you attempt intermittent fasting).

THE BEST 2 WAYS TO INTERMITTENLTY FAST

Method 1:

Some people eat all their calories within 8 hours per day, fasting for the other 16 hours. This can work, for example, by skipping breakfast and eating only between 12:00 p.m. until 8:00 p.m.

During the fasting times, you can drink water, coffee (only 1 please, and high quality) or tea, provided they don’t contain any sugar.

Method 2:

Another way to do IF is by eating normally five days of the week. On two non-consecutive days that week, eat no more than 600 calories.

For people who start IF, there is a transition period of 3-6 weeks. During this time the body and brain adapt to the new eating pattern, and I find some people even notice improved mood.

SHOULD I INTERMITTENTLY FAST?

One recent study says:

“...we conclude that there is great potential for lifestyles that incorporate periodic fasting during adult life to promote optimal health and reduce the risk of many chronic diseases, particularly for those who are overweight and sedentary.” (Longo et al., 2014)

In my opinion though, IF is not for everyone (I think this will be my third time saying it so hear me! Fix your hypoglycemia before you try intermittent fasting!)

IF should also be avoided in children, the elderly, and adults who are underweight. We also know that it can be harmful for people with certain medical conditions, such as amyotrophic lateral sclerosis (ALS, i.e. Lou Gehrigs Disease). Even as a healthy adult there may be times when IF makes you super hungry, or physically and mentally fatigued. If you attempt IF a few times and repeatedly feel really crummy, then just eat (a complex carb with a fat or protein). IF just might not be right for you at this time, and you can try it again in a few months.

My two cents on IF is that it’s a beneficial way of eating with some good emerging evidence to back it up. Like I said, I’ve tried it and like it (but I’ve also spent years working on fixing my blood sugar). However, I’m hesitant to recommend it to clients as part of their NeuroTrition Rx because, while the science is cool, so far it is mostly in rodents or really small samples with humans. But I think if your blood sugar is stable, and you’re really itching to try it, then give it a go. Try one of the ways I recommend above and see if it’s something that works for you.