Through intermittent fasting and controlling calorie intake, the human body can increase the number and function of stem cells, which are important for slowing down our aging process and reducing inflammation. What is intermittent fasting? What are the benefits of intermittent fasting? How do we know if we are suitable for intermittent fasting?
“Fasting” means not eating or drinking anything containing calories for a period of time. One can drink water, black coffee, or other calorie-free drinks.
Types of Fasting Methods
Founder and former CEO of Twitter Jack Dorsey told the press that he only eats once a day between 6 pm and 9 pm, which consists of protein and vegetables. Fasting helps him feel more focused and able to concentrate more on his daily life.
Skipping breakfast and lunch, Jack gets more time to focus on important things. This method of intermittent fasting is known as “samurai fasting,” or OMAD (one meal a day). In ancient times, samurai did not eat three meals a day but had a large dinner instead. This method allows people to drink water, black coffee and low-calorie items for 20 hours and consume high-calorie foods during the remaining four hours of the day.
However, the evening may not be the healthiest time to eat a big meal.
Chris Pratt, star of Guardians of the Galaxy, tells his fans that intermittent fasting is a “must try.” Pratt claims fasting helps him play superheroes well in his films. He says he usually drinks coffee and exercises before noon and doesn’t eat anything after 8 p.m. His intermittent fasting method is called 16/8 intermittent fasting or “time-restricted eating.” This method involves limiting food and drink intake to a set window of eight hours a day. Some suggest that 18 hours, rather than 16 hours, produces better results.
Jimmy Kimmel, the American late night talk show host, lost excess weight by fasting two days per week. Although he consumed little food and drink for two days (Monday and Thursday) he kept his intake within 500 calories.
Jimmy said he got the idea from a BBC documentary about a 138-year-old Indian man whose secret to staying young was limiting his calorie intake through fasting. He introduced the fasting method as the 5:2 diet: eat five days regularly and eat less than 500 calories for two days.
There are many celebrities, bodybuilders and online influencers sharing and promoting their intermittent fasting experiences.
Although they may not be experts in medicine or health, they have a great influence on people by sharing their personal experiences.
Is celebrity endorsement making intermittent fasting just a healthy trend? Or is it scientifically supported? How are real experts on the topic considered?
Recently, the New England Journal of Medicine released a collaborative review titled “Effects of Intermittent Fasting on Health, Aging, and Disease.” The article comprehensively summarizes the results of intermittent fasting research.
Three types of intermittent fasting have been studied, including Alternate Day Fasting (ADF), the 5:2 diet, and OMAD.
Benefits of Intermittent Fasting
What are the benefits of intermittent fasting?
1. Anti-aging
Eating less can help our bodies produce fewer harmful metabolites, including free radicals. More importantly, it can increase the reactivity of cells and organs, promote blood sugar regulation and stress resistance, and at the same time suppress the inflammatory response.
Free radicals are unstable molecules created during normal cell metabolism (chemical changes that occur in cells). Free radicals can accumulate in cells and cause damage to other molecules, such as DNA, lipids, and proteins. This damage can increase the risk of cancer and other diseases.
A lifestyle of eating three meals a day, occasional snacks in between, and mostly sitting, is harmful to our bodies. More exercise and consuming adequate or limited calories is beneficial for health. Intermittent fasting protects and heals our body.
2. Weight loss.
Normally the body offers energy through converted glucose from the consumption of carbohydrates, fruits and vegetables. In overeating, the liver will convert excess glucose into fat and store it. Overeating, not enough exercise, and sitting too much, cause stored fat to be stored in our body. Fasting for more than 16 hours causes the body to use stored glycogen first, then burn fat. The dissolution of fat will produce ketone bodies that offer energy to our brain and play an important role in sending signals between organs and participating in cell and organ functions.
3. Turn on autophagy
During fasting, a series of chemical reactions occur in the body, including promoting antioxidant mechanisms, restoring inherited DNA material, improving protein quality, increasing ATP synthase in mitochondria, cell self-renewal functions, and reducing inflammation. The function of cell self-renewal is performed by a mechanism called autophagy. It is very important for the recovery of our body.
4. Improve chronic diseases
Intermittent fasting not only helps weight loss, but can also increase the body’s sensitivity to insulin to reduce blood lipids, blood sugar, and blood pressure thus improving chronic inflammatory diseases.
Researchers divided 100 obese women into two groups—one group reduced food consumption by 25 percent, and the other group underwent a 5:2 diet. After six months, both groups lost the same amount of weight, but the 5:2 diet group had greater sensitivity to insulin and a clear loss of belly fat.
5. Increase endurance and exercise performance
Researchers compared the level of physical activity of mice that underwent ADF and had a normal diet. ADF rats had significantly better running endurance than rats fed regularly and showed better balance and coordination ability. In addition, young men, who fasted for 16 hours, lost fat without losing muscle.
6. Prevention of cancer
Most animal research has found that restriction of caloric intake and ADF can reduce tumor risk, inhibit tumor growth, and increase tumor sensitivity to chemotherapy and radiotherapy. The curative effect is shown to be significantly increased.
7. Reduce the development of Alzheimer’s and Parkinson’s disease
Through animal research, it has been found that both the occurrence and progression of Alzheimer’s and Parkinson’s can be delayed through ADF. Intermittent fasting brings many benefits to our brain, including promoting neuronal remodeling to cope with nutritional stress, strengthening brain mitochondrial function, stimulating cell renewal and generation of neuroprotective factors, antioxidant function, and restoring inherited genes.
8. Reduces immune diseases
Recent research has found that if multiple sclerosis (MS) patients continue intermittent fasting, disease symptoms improve within two months. This may have something to do with the function of reducing inflammation.
Therefore, it can also benefit rheumatoid arthritis and other immune diseases. MS is a potentially disabling disease of the brain and spinal cord. In MS, the immune system attacks the protective sheath (myelin) that covers nerve fibers and causes communication problems between your brain and the rest of your body.
9. Reduction of damage caused by tremors
This may come as a surprise—repairing damage such as memory loss, poor concentration, increased irritability, and hypersomnia from concussions is an unexpected boon for people with brain injuries.
One important benefit of intermittent fasting is that it can directly activate the anti-aging tunnels in our body and thus reduce the aging process.
Three Notes to Consider in Intermittent Fasting
What type of intermittent fasting is right for you? In learning about the various benefits of intermittent fasting, many people are willing to give it a try. Here are some things to consider.
- While there are many benefits to fasting, it can be challenging. Many people are used to eating three meals a day and also have snacks. The influence of advertisements that attract consumers with an endless variety of tempting foods makes abstinence difficult. To fast, absolute determination is required.
- Many people feel misaligned when they start fasting. During fasting, a person feels hungry, may be irritable, and lack concentration, but these symptoms will gradually disappear within a month. One has to be mentally prepared to fast.
Fasting through breakfast may be an easier option than fasting through dinner—however, since dinner tends to be a larger meal, skipping a meal may yield better results. Also, skipping dinner doesn’t tend to affect sleep quality like skipping breakfast. It is not recommended to fast every day in the beginning. You can gradually increase the fasting time from day to day starting from 12 hours and gradually increase to 18 then 20 hours.
- If you have any current medical conditions such as diabetes, do not attempt fasting without first consulting your doctor. Just control your eating habits under the supervision of a doctor. You may want to try a few weeks on the Mediterranean Diet before fasting.
According to the Taiwan Society for Nutritional Psychiatry Research, the Mediterranean Diet is a comprehensive eating habit. It encourages consumption of fruits, vegetables, nuts, whole grains, fish, and healthy oils, and choosing natural foods over processed foods to reduce inflammation.
How to Practice Intermittent Fasting
If you have read the article up to this point, you probably feel ready to fast. There is a correct approach recommended for safe and effective fasting.
For ADF, a person eats a normal, nutritious meal one day then eats less than 500 calories the next day.
For the 5:2 fast a person eats a normal meal on weekdays then consumes less than 500 calories on each weekend day. In addition to both, a person has 16 hours a day between meals.
Westerners sometimes promote skipping breakfast and finishing their meals between noon and 8pm but eating between 7am and 3pm is more compatible with our biological clock. When you have a late dinner, the body releases melatonin, affecting the quality of sleep— and the digestive system does not work well during sleep.
Be careful not to overeat during non-fasting hours. Continue to enjoy regular sized meals and a balanced diet with two parts fruits and vegetables, one part animal or plant protein, one part carbohydrates and some healthy fats. In addition, slow down your meal times to allow for greater satiety and healthy digestion.
Depending on your own situation, you can start intermittent fasting with one weekend day and gradually increase to make sure you reach your goal.
Dr. Jingduan Yang is a faculty member at the University of Arizona Center for Integrative Medicine, former assistant professor of psychiatry and director of the Oriental Medicine and Acupuncture Program at the Jefferson-Myrna Brind Center for Integrative Medicine at Thomas Jefferson University. He completed a research fellowship in clinical psychopharmacology at Oxford University, residency training in psychiatry at Thomas Jefferson University in Philadelphia, and a Bravewell Fellowship in integrative medicine at the University of Arizona. You can learn more about Dr. Yang at its website www.YangInstitute.com.
