Not so FAST: The significance, benefits, and hazards of intermittent fasting

As Ramadan started this week, Muslims around the world fast from dawn to sunset, and some European Muslims restrain from eating or drinking for up to 21.02 hours. Muslims fast during Ramadan, Christians during Lent, Jews during Yom Kippur and Tisha B’Av, Jains during Paryushana, and Hindus fast several times a month. While fasting is a common ritual in many religions, it is also used as a means of fitness. There are both physical benefits and risks to fasting, as well as spiritual and mental advantages.

Intermittent fasting is a hot fad in the fitness world. It limits a person’s eating periods rather than food choices, requiring a person to abstain from caloric intake for a certain period of time, and then indulging. The idea of intermittent fasting traces to theories of the way humans dealt with famines and surpluses before agricultural advances popularized. Our hunter-gatherer ancestors were unable to eat substantial meals for prolonged periods of time, and when they acquired food, they had to eat it quickly, before it spoiled. Therefore, the human body adapted to handle a cycle of starvation followed by feasting, and there are both health benefits and health hazards to this kind of physical strain.

A study by the Intermountain Medical Center Heart Institute shows that fasting stimulates the production of HGH, the Human Growth Hormone, and may prevent against coronary heart disease and insulin-resistant diabetes. Another study by the National Institute on Aging Intramural Research Program shows that fasting may improve the health of overweight subjects by enhancing cardiovascular and neurological function. It supports the idea that fasting may help in reducing blood pressure and increasing insulin sensitivity. However, it also shows that simply reducing caloric intake may result with the same health perks. Verily, fasting is not the only route to exceptional health. In addition, fasting is not the best way to lose weight because it only does so through fluid loss. A study by Sadeghirad et al. shows that the weight typically lost through intermittent fasting is often gained shortly after the fasting period ends. Fasting may in fact hinder weight loss as it slows the rate of metabolism; when a pre-fasting diet is reintroduced after fasting, it may be more fattening that it was before. The evidence for whether or not fasting detoxes the body is ambiguous, with some claiming that the body’s liver, two kidneys, colon, and skin already do an extremely effective job at detoxification, and the other side claiming that ketosis, or the burning of fat, abolishes toxins consumed through unhealthy, processed foods.

Fasting may be hazardous to those with preexisting health issues such as diabetes, liver or kidney problems, immune system complications, a history of cardiac arrhythmia, malnutrition or wasting diseases, eating disorders, or those who use certain medications including Tylenol. Moreover, Islamic teachings forbid pregnant women from fasting during Ramadan because it is dangerous for the health of the woman and the fetus.

Since intermittent fasting does not provide any guidelines for the types of food to avoid and eat, it is dangerous to assume that it is a healthy route to fitness. A person can fast intermittently and still have a diet of predominantly fried foods, red meats, processed snacks, and sugary drinks. A person who fasts intermittently may not even consume any fruits, vegetables, nuts, or whole grains. A study that followed thirty six healthy males before and after Ramadan indicates that their caloric consumption per day had no significant differences when they were fasting versus when they were not fasting. Intermittent fasting does not restrict calories or unhealthy foods, so it is not evident that fasting provides more health benefits than simply eating balanced meals, sleeping adequately, exercising regularly, and avoiding smoking and alcohol. As dietitians and other health experts repeatedly recommend, balance is key. Although fasting does have health benefits and is a “natural” human activity, it is not a viable way to lose weight and comes with many health risks.

While the health benefits of fasting can also be achieved through other means of reducing caloric intake, the spiritual and mental benefits are one-of-a-kind. A study by Fond et al. shows that fasting may help ease depression symptoms and may be associated with improved mood, a feeling of wellbeing, increased alterness, and sometimes euphoria. Fasting also aids in anti-aging mechanisms. A study by Alirezaei et al. shows that fasting increases neuronal autophagy in mice, a process in which the brain rids and repairs itself of dysfunctional neuronal cells. Low neuronal autophagy is linked to increased risk of neurodegenerative diseases, so boosted neuronal autophagy resulting from fasting is a phenomenal health reward. Not only does fasting provide mental benefits in regards to decreased depression symptoms and neurological anti-aging methods, but the joy of breaking a fast during Ramadan with friends and family is immeasurable.

While fasting may be easy for people with access to comfortable living and working conditions as well as an abundant amount of food and water, it can be very arduous for those who perform intense work for minimal wages in bad climate circumstances, with low access to food to break their fasts with. Yet, people all over the world continue to fast for tradition and faith. The human body is indeed very strong and resilient, and while there are health risks to fasting, the spiritual benefits are mysterious and unknown until one engages in the activity.