Fasting for Immunity
Trying to avoid getting sick during cold and flu season may seem like trying to dodge raindrops in a rainstorm. Boosting your body’s immune system is critical in helping to fight off various illnesses. Fasting comes with a variety of health benefits; but did you know that studies are suggesting that it may also help give your immune system an upper hand in keeping those nasty viruses at bay?
What Is Fasting?
Fasting is intentionally abstaining from eating for a certain period of time. People choose to fast for a variety of therapeutic, spiritual or political reasons.
There are various forms of fasting which can include:
- Intermittent fasting: involves the combination of periods of eating and periods of fasting.
- Time restricted fasting: aligns mealtimes with your natural circadian rhythm and encourages eating the majority of meals as early in the day as possible.
- Fasting with water: abstaining from eating and drinking with the exception of water.
- Fasting with juice: abstaining from eating and drinking with the exception of fruit and/or vegetable juice.
- Alternate day fasting: eating one day while abstaining from eating the next day.
- Prolonged fasting: abstaining from eating for 48 hours or more.
- Dry fasting: abstaining from eating or drinking anything for a period of time.
Each of these methods has different pros and cons. The one you choose will depend on your health and goals.
How Fasting Boosts Your Immune System
Your immune system is constantly bombarded with foreign invaders which may try to weaken it. From stress and unhealthy foods to exposure to viruses and bad bacteria, your body is constantly under “attack”. These attacks can wreak havoc on your immune system leaving you more vulnerable to illness. Thankfully, what you eat (or don’t eat) may help defend your immune system against various invaders.
Encourages White Blood Cell Production
Keeping your white blood cells in tip-top shape can help strengthen your immune system making it easier for your body to fight foreign invaders. Your white blood cells, also known as leukocytes, are the cells that fight against viruses and bacteria.
Laboratory and animal research suggests that fasting not only prompts your body to use stored glucose and fat, it also breaks down white blood cells. Breaking down white blood cells triggers the production of new, robust white blood cells that are more efficient in fighting viruses. Fasting can essentially help to regenerate a new, more effective immune system. 
Produces Ketones that Suppress Inflammation
Another way in which fasting may boost your immunity is through the production of a specific ketone known as beta-hydroxybutyrate (BHB). During fasting your body will start to break down fat as a fuel source. The process of fat breakdown produces ketones which your body can use for energy.
BHB is a ketone that may benefit the immune system by decreasing inflammation. In laboratory studies of human tissue, researchers found that BHB may block a part of the immune system that is involved in autoimmune diseases, type 2 diabetes, the buildup of arterial plaque, and Alzheimer’s disease. 
Fasting can also activate autophagy.  Autophagy is your body’s system of cleaning out old, damaged cells, and replacing them with newer, healthier ones. Autophagy plays an important role in your body’s immune system by clearing out toxins and dangerous bacteria. Additionally, autophagy may play a role in encouraging immune-mediated cells to release antibodies and cytokines (proteins that help regulate the immune system), further enhancing the efficacy of the immune system. 
Potential Health Benefits of Fasting
No matter which form of fasting you choose, fasting comes with health benefits beyond that of boosting your immune system. These may include slowing the aging process, decreasing risk of heart disease, and improving cognition. 
Reduced Risk of Heart Disease
According to recent research intermittent fasting can improve heart health. Fasting limits many risk factors for the development of cardiovascular diseases, which intuitively may help to reduce the occurrence of these diseases. Intermittent fasting has been shown to decrease blood pressure, resting heart rate, cholesterol levels, triglycerides, and blood sugar. 
In animal studies, alternate-day fasting may delay the onset and progression of Alzheimer’s and Parkinson’s disease. 
Additionally, research suggests that intermittent fasting may enhance cognition including spatial memory, associative memory, and working memory. 
In a 2017 study, researchers were able to show that fasting may increase lifespan and slow aging by changing the activity of mitochondrial networks inside cells. Within cells, the mitochondrial network is constantly reshaping itself to adapt to lifestyle and environmental changes. During the aging process, the mitochondrial network activity tends to decline. Fasting can help maintain “mitochondrial fitness” which helps combat the aging process. 
Other Ways to Boost Your Immune System
During cold and flu season it’s nice to have a variety of things you can do to help bolster your immune system. In addition to fasting, there are other steps you can take to help keep your immune system strong and working efficiently.
General healthy-living strategies to help your immune system healthy may include:
Eating a well-balanced diet that includes a variety of fruits and vegetables.
Fruits and vegetables are chock full of powerful antioxidants. Antioxidants can help decrease inflammation by reducing the levels of free radicals in your body. Chronic inflammation can leave your body more susceptible to viruses and is also linked to various health conditions, including heart disease, Alzheimer’s, and diabetes. 
Water can support your immune system by ensuring that your lymphatic system is working efficiently. The lymphatic system relies on lymph which is made up of mostly water. Being dehydrated may lead to less lymph production. A robust lymphatic system helps to remove toxins, pathogens, and dead cells from the body. Additionally, the lymphatic system helps to circulate infection-fighting white blood cells throughout the body.
Getting plenty of sleep.
While it may be easier said than done, aiming for 7 or more hours of sleep will help to strengthen your immune system naturally. One study showed that healthy adults who slept for less than 6 hours per night were more likely to catch a cold than study participants that slept more than 6 hours per night. 
Participating in physical activity on a regular basis.
Moderate exercise can give your immune system a nice boost. Try aiming for 150 minutes of exercise per week. Examples of moderate exercise include walking, bicycling, swimming, and dancing.
Fasting may help to bolster your immunity by increasing healthy white cell production, creating helpful ketones that may suppress inflammation, and by cleaning out toxins and harmful bacteria. In addition to fasting, there are several dietary and lifestyle changes that may reinforce your body’s natural defenses. Giving your immune system the upper hand against fighting harmful pathogens will keep you feeling great all year long.