Can Intermittent Fasting Boost Your Immune System?

What is intermittent fasting?


Intermittent fasting has become a popular practice among the health and fitness industries. It is a practice of cycling between phases of fasting and eating. 


This diet practice emphasizes when you can eat, rather than what you can eat – contrary to many other diet fads. 


The goal of intermittent fasting is not simply to just restrict calories, but rather, to enable the body to focus its energy towards maintenance and recovery instead of towards digestion. 


Empty plate with a knife and fork against a blue table


The different types of intermittent fasting 


There are several patterns of intermittent fasting that people may choose to adopt. Common practices involve fasting for 16 hours daily, or even 24 hours a couple of times per week. 


In the 16-hour fast practice, each day would have an 8-hour eating window – for example, a person could eat between the hours of 10 am and 6 pm, while fasting the other hours of the day.


Others may choose to skip breakfast, having their first meal at noon and their last meal at 8 pm. This pattern of fasting is also referred to as the 16/8 method. 


Knife and fork on a wooden plate forming a clock


Some people choose to complete a 24-hour fast once or twice per week. Others may choose to have a significant calorie restriction to 500-600 calories daily for 2 days each week. 


While all of these methods count as intermittent fasting, the most popular and simple method to adopt is the 16/8 method. 


What happens to your body when you do intermittent fasting?


There are significant changes that occur in the body during intermittent fasting. Cells become more efficient at important repair processes.


Here is a list of some important changes that occur in the body with intermittent fasting:


Reduced insulin resistance


Intermittent fasting, or fasting in general, causes insulin levels to decrease. 


A recent study showed that intermittent fasting significantly reduced insulin resistance, even when total calories were not reduced. When the body has less insulin resistance, and therefore greater insulin sensitivity, the immune system is one of the physiological systems that benefits. 


In fact, clinical evidence shows that immune cell responses to pathogens are negatively altered in those individuals with insulin resistance (1).


Reduced inflammation


It is widely acknowledged that inflammation in the body is often a root cause of aging and the development of many chronic diseases. People may even be more susceptible to the common cold with increased levels of inflammation. 


Graphic showing the health problem links to chronic inflammation


Intermittent fasting may play a vital role in reducing inflammation, which in turn damages cells through what is known as oxidative stress (2). 


Reduced cellular waste 


Short-term fasting increases cell autophagy, which is essentially the cell’s cleansing process. In this process, damaged cells are cleaned out in order for new, healthy ones to regenerate. 


Intermittent fasting may in fact be one of the best practices to encourage this cell cleansing process. Plus, the more cellular waste that is disposed of, the stronger the immune system will be (3, 4).


Why do people practice intermittent fasting?


People are using intermittent fasting for weight-loss and to improve overall health. If done correctly, intermittent fasting can improve many biological systems such as muscle growth, immune function, mental clarity, cardiovascular health, blood sugar regulation, and improving the health gut microbiome. 


One of the most widely supported areas of research about intermittent fasting is its ability to significantly boost the immune system. 


Can intermittent fasting boost your immune system?


As a result of the physiological changes that occur with intermittent fasting, the immune system strengthens. Periods of fasting improve insulin sensitivity, reduce inflammation, reduce cellular waste, as well as enhance the action of immune cells and cytokines (5).


Intermittent fasting creates an eating pattern that aligns with our circadian rhythms. Circadian rhythms regulate much of our physiology, and the immune system is trained to fluctuate in accordance with them.


The intermittent fasting pattern of fasting for 16 hours and eating for 8 hours, aligns with the body’s sleep and wake cycles, which in turn aligns with the optimal functioning of the immune system (6). 


Fasting also reduces levels of insulin-like growth factor 1, or IGF-1, as well as reduces levels of protein kinase A, or PKA, which is a key regulator of immune responses in the body. In fact, lower levels of IGF-1 are associated with improved health and a longer lifespan (78). 


What is the best food to eat after fasting?


After coming out of a fasting period, it is best to consume highly nutritious foods that are easy to digest and also contain some protein. 


For example, some great meals to break a fast might be a smoothie, soup, eggs, or oatmeal for example. It is important to break your fast with nutrient-dense foods to replenish nutrients and ensure you are meeting your needs. 


Naked Collagen product next to a collagen berry shake


Break your fast with collagen protein


Specifically, consuming a collagen protein after intermittent fasting may be one of the best types of proteins to use. Collagen peptides are easily digested and absorbed, and the amino acids are then readily used by the body (9). 


Additionally, collagen protein may have an added effect of strengthening the lining of the gut, which in turn makes for a stronger immune system. 


Our collagen protein powder is sourced from grass-fed and pasture-raised animals and has no other added ingredients. Also, it does not change the taste or texture of the food it’s added to, making it super versatile. 


The following gut-friendly collagen smoothie is the perfect combination of nourishing ingredients to consume when breaking a fast. 

For added muscle benefits you can also add some BCAAs to the smoothie to break your fast

Gut-Friendly Collagen Smoothie:



  • 1 banana
  • 1 handful spinach 
  • ½ cup frozen raspberries
  • ½ cup plain Greek Yogurt 
  • 1 cup of milk (cow’s milk or your favorite non-dairy alternative)
  • 1 scoop of Naked Collagen
  • 2-3 few ice cubes


Directions: Blend all ingredients together and enjoy!