Fasting has long been a part of many religious traditions, including the Jewish and Muslim holidays of Yom Kippur and Ramadan, respectively. As you read this, billions of Muslims around the world are participating in this act of faith, which involves fasting from dawn to dusk. While fasting for Ramadan is based on spiritual beliefs, many of us fast because we believe it benefits our health. However, what happens to our bodies when we fast?
The primary source of energy for a person is glucose, which is obtained from carbohydrates such as grains, dairy products, fruits, certain vegetables, beans, and even sweets.
The glucose is stored in the liver and muscles and released into the bloodstream when the body requires it. This process, however, changes during fasting. The liver will deplete its glucose reserves after about 8 hours of fasting. At this point, the body enters a state known as glucogenesis, which marks the transition into fasting mode.
Glucogenesis has been shown in studies to increase the number of calories burned by the body. Without carbohydrates, the body burns its own calories. When there is no carbohydrate available, the body produces its own glucose, primarily from fat.
The body eventually runs out of these energy sources as well. Fasting mode then transitions into the more serious starvation mode. A person's metabolism slows down at this point, and their body begins to burn muscle tissue for energy. Although it is a well-known term in the dieting world, true starvation mode occurs only after several days or even weeks without food. So, unless other health conditions exist, it is generally safe to go without eating for a day after breaking their fast after 24 hours. (1)
“A detoxification process also occurs, because any toxins stored in the body’s fat are dissolved and removed from the body,” he adds, noting that after a few days of fasting, higher levels of endorphins – “feel-good hormones” are produced in the blood, which can have a positive impact on mental well-being. As mentioned previously, the study by Dr.Longo and colleagues suggests prolonged fasting may also be effective for regenerating immune cells. “When you starve, the system tries to save energy, and one of the things it can do to save energy is to recycle a lot of the immune cells that are not needed, especially those that may be damaged,” Dr.Longo explains. In their study, publish in the journal Cell Stem Cell, the team found that repeated cycles of 2 – 4 days without food over a 6-month period destroyed the old and damaged immune cells in mice and generate new ones.
Furthermore, the team discovered that cancer patients who fasted for three days prior to chemotherapy were protected against immune system damage caused by the treatment, which they attribute to immune cell regeneration. "The good news is that the body got rid of the parts of the system that might be damaged or old, the inefficient parts, during the fasting," says Dr. Longo. "Now, if you start with a system that has been heavily damaged by chemotherapy or ageing, fasting cycles can literally generate a new immune system." (2)
Intermittent fasting, on the other hand, is associated with numerous health risks, according to the UK's National Health Service (NHS).
People who fast frequently become dehydrated, owing to their bodies' inability to obtain fluid from food. As a result, it is advised that Muslims consume plenty of water prior to fasting periods during Ramadan. Other people who follow fasting diets should stay hydrated during their fasting periods.
On the other hand, according to the UK’s National Health Service (NHS), there are numerous health risks associated with intermittent fasting.
Fasting can also cause heartburn; lack of food leads to a reduction in stomach acid, which digests food and destroys bacteria. But smelling food or even thinking about it during fasting periods can trigger the brain into telling the stomach to produce more acid, leading to heartburn.(2)
Finally, to sum up, moderation is the key. Know the precaution step to avoid the potential risk. A person must understand his or her current health condition before proceeding to any sort of diet plan.
Fasting can also cause heartburn because a lack of food reduces stomach acid, which digests food and destroys bacteria. However, smelling food or even thinking about it during a fast can cause the brain to tell the stomach to produce more acid, resulting in heartburn. (2)
To summarize, moderation is essential. Understand the precautionary measure to avoid the potential risk. Before beginning any diet plan, a person must first understand his or her current health situation.
Medical News Today (n.d). What Happens If You Don’t Eat For A Day? Timeline And Effects. [online] Available at: https://www.medicalnewstoday.com/articles/322065#can-fasting-promote-weight-loss [Accessed 29 April 2020].
Medical News Today (n.d). Fasting: Health Benefits And Risks. [online] Available at: https://www.medicalnewstoday.com/articles/295914 [Accessed 29 April 2020].