How Fasting is Beneficial for Brain Health & Inflammation

Everyone knows the benefits Fasting has weight loss and energy but many people do not know the considerable benefit it has on our brain health & inflammation in the body.

Research has shown the Fasting may reduce Autoimmunity of the body and in 1 study showed that it can reduce the risk of developing Parkinson's and Alzheimer's Disease. This occurs by stimulating neural messaging chemicals such as Brain Derived Neurotrophic Factor (BDNF). BDNF plays an important role in creation of new brain cells.

Other research has shown that Fasting may reduce overall inflammation in the body. A 24 hour Fast has been shown to deactivate the human NLRP3 Inflammasome. This inflammasome is a part of the bodies immune system and is responsible for activating a inflammatory response. Studies and research suggest that fasting may create mitachondrial resiliance and prevent inflammation.

Why should you care about your BDNF? As mentioned earlier, BDNF is responsible for Nueroplasticity, which is the brains ability to rewire itself creating new neural pathways and reinforce familiar neural connections. This is particularly important in learning or trying to create new habits and overwrite old habits that do not serve us or our health. You can control your BDNF through Nutrition, some examples of this are reducing sugar, as sugar reduces our BDNF, increasing our Omega 3 Fatty acids which supports BDNF. Sleep also affects our BDNF, if its is inadequate or poor in quality, many of us do not consider how sleep or lack of could be affecting our health goals and in reality it can be one of the most simplest things to change. Moving our bodies at any age will help to improve our BDNF & chronic stress which increased our cortisol levels and affects our adrenals decreases our BDNF levels.

What type of Fasting do you need to do to increase BDNF? A minimum of 3 days Fasting is recommended. Yes that is 72 hours and you would be surprised at actually how easy it is. Extended periods of fasting is natural for the body. Our ancestors went days without food as food wasn't always readily available. Today we live in a society of convenience, our cupboards are packed full of readily accessible food, majority being high in processed carbs and trans fats. We tend to eat with our eyes or because we know it is there. Imagine if we reduced the amount of food we have on hand how much healthier we would be, how more in control of our appetite we would be, not to mention the $$$ we would save. "Food for thought" pardon the pun.

When food is always available we need to do intentional fasting (we make the decision to fast) to reduce the stress on our body and digestive system. Whilst a 3 day fast will bring benefits to your body, physically, mentally and some spiritually, it also is a form of stress on the body, therefore some may experience some unwanted symptoms. Here's a breakdown of what you could expect.:

Day 1 - Unless your are already keto and or practice keto in conjunction with fasting, your body is unfortunately use to using sugar as its primary energy source. Over the 3 days of fasting your body will adapt and swing over to using fat for fuel. You may experience your typical detox or cold/flu symptoms, you may be lethargic, hungry, have cravings, experience headaches, have bad breath or feel dehydrate & even feel generally unwell. Do not stress this is quite normal and is happening because your body is transitioning from burning sugar to burning fat, its cleansing and detoxing and starting the repair process from months or years of damage.

Day 2 - Is all about the Gut, the body is getting rid of the bad bacteria and balancing out your gut microbiome. Your hunger and craving start to diminish but emotionally you may feel out of wack, you may be a little more fatigued, experience brain fog and you may be a little moodier. Your body is working hard to detox, removing fungi, bad bacteria and toxins. Your tongue may have and yellow or white coating and some may have black. Others may experience skin rashes.

The body also starts deregulating the thyroid, so you may feel cold or get shivers, this is normal and means that the fasting is helping to hormone sensitivity telling the body it needs less hormones and insulin to function. The body is now experiencing autophagy, that cellular clean up of dis-functional cells and repairing damaged cells, we also have an increase in Human Growth Hormone production which supports maintaining muscle, improves strength and increase bone density.

Day 3 - The body experiences a large rise in ketones. HGH, Stem Cell production and Autophagy also increases. Your blood sugar starts to stabilise and you will start to feel better. You may notice more energy, less pain, and you should feel mentally sharper, more clarity and alert. If you were not keto adapted before, you may still experience fatigue, brain fog and some of the other symptoms, but do not fear, your body is still working hard and by the time you are ready to break your fast, chances are you will be feeling better than ever.

How should you prepare? Whilst doing a 3 day fast is super beneficial. It is recommended to prep yourself before going into it. This can reduce the symptoms and increase the benefits. It is recommended a 2-3 days before the fast to cut back or preferably stop all processed and refined carbs, things like cakes, biscuits etc... if it doesn't come out of the ground or is in a packet off a shelf do not eat it. This will help you get into ketosis quicker.

Start drinking plenty of water and gradually increase, water will be your friend during the fast and will also help move toxins out of the body and reduce symptoms, aim for 2-3 Lt a day but gradually over the day, you do not want to stress your kidneys if you are not use to drinking a lot of water.

Have some good salt on hand, Himalayan or Rock Sea Salt is great, this will help to balance your electrolytes during your fast and can also help with headaches.

Pre-prepare meals for the family during your fast, try to minimise the time in the kitchen, especially if this is new to you, the less temptation the better. Explain to your family what and why you are doing this. If you have impressionable kids that you are concerned about telling them about fasting or why you are not eating, if they are old enough explain the science, if not simply explain you are eating later. Fasting should never have a negative impact on anyone but considering others especially if they have a negative relationship with food is important as fasting is not recommended in this circumstance unless under medical supervision.

Create a low key schedule over the 3 days you are fasting and set up your bed time routine, aim to get 8 hours of sleep each night and plan some me time. This could be taking a bath, having a spa treatment, doing some gentle yoga, do what ever makes you feel good but wont add additional stress to your body. Honour yourself and what you are experiencing.

Get a journal and record what you're experiencing, this is a great reflection for future reference.

Who should not Fast? Fasting is not recommended for everyone, those with eating disorders, pregnant or lactating women, young children, athletes in season, those that are severely underweight, those on medications and individuals with Type 1 Diabetes. It is recommended that everyone that is new to fasting, seek medical advise first or a general health check up to ensure there is no underlying conditions.

How to Correctly break a 3 day Fast! Breaking your fast is just as important and preparing. Your body and digestive system has been resting, repairing and detoxing with no food for 3 days. Eating too much too soon can put the body at stress creating some uncomfortable symptoms and digestive discomfort. Refuelling with heavy foods, too much sugar or junk food is counterproductive to what you've just done. The re-feeding phase after a 3 day fast should be gentle and aim to reduce any symptoms of re-introducing food back into your body. For every 2-3 days of fasting you should have a recovery day of gradually increasing calories without over stressing the system. The first day after the fast you should consume 50% of your recommended caloric intake and the second day be back to your normal caloric intake. But calories are not all the same!! The quality of the food you eat matters, keep it fresh avoiding unhealthy food, ingredients and additives. Whats the point of putting the chemical toxins back into your body when you've worked so hard to remove them! On that first day be gentle, aim for liquid foods, bone broth, green smoothies, protein shakes and soup are all ideal. Once you feel you are ready to move onto solids, aim for steamed vegetables, fermented foods, healthy fats like avocado's. Once back to your normal calorie intake then start eating meats, nuts, dairy, eggs and starches.

In summary - the immune system is meant to protect you against bacteria, viruses, parasites, toxins and other harm. For your immune system to function optimally you must support it through optimal nutrition and lifestyle. Research has shown a 3 day fast can reboot your immune system creating a big difference to your health and wellbeing.

References for the BLOG:

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Wu, S. Fasting triggers stem cell regeneration of damaged old immune system. USC News.

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