Could Eating Less Actually Be Good For You? The Science of Fasting

Vocabulary Review

Deliberately (adv.) – doing something on purpose, not by accident.

Example: She deliberately left her phone at home so she could relax during her vacation.

Fast (v.) – to choose not to eat for a certain period of time.

Example: Some athletes fast for a short time before medical tests.

Conscious (adj.) – done with awareness and intention.

Example: He made a conscious effort to drink more water every day.

Kidding (v./expression) – saying something as a joke and not seriously.

Example: “You owe me a million dollars,” she said, then laughed, “I’m just kidding.”

Intermittent fasting (n.) – a way of eating where you only eat during certain hours of the day.

Example: Many people try intermittent fasting by only eating between 10 a.m. and 6 p.m.

Window (n.) – a limited period of time when something is allowed or possible.

Example: We only have a short window to register for the course before it closes.

Extended fasting (n.) – fasting for a longer period of time, usually more than a full day.

Example: Some people attempt extended fasting during health retreats.

Rumors (n.) – information or stories that people talk about but that may not be true.

Example: There were rumors that the company was going to close, but nothing was confirmed.

Fatigued (adj.) – very tired physically or mentally.

Example: After working a 12-hour shift, the nurse felt completely fatigued.

Foggy (adj.) – when your mind feels unclear or slow and it’s hard to think.

Example: I felt mentally foggy after staying up all night studying.

Sharp (adj.) – quick and clear in thinking.

Example: Even at 80 years old, his memory is still very sharp.

Suddenly (adv.) – quickly and unexpectedly.

Example: The lights suddenly went out during the storm.

Bypass (v.) – to avoid or go around something.

Example: The driver used a side road to bypass the traffic jam.

Inevitable (adj.) – certain to happen and impossible to avoid.

Example: After hours of arguing, it seemed inevitable that they would cancel the meeting.

Boost (v./n.) – to increase or improve something.

Example: A short walk outside can boost your mood.

Stem-cell (n.) – a special type of cell that can develop into different kinds of cells in the body.

Example: Scientists study stem cells to better understand how the body repairs itself.

Limb (n.) – an arm or a leg of a person or animal.

Example: The athlete injured his limb during the soccer game.

Chronic (adj.) – a health problem that lasts a long time or keeps coming back.

Example: She suffers from chronic back pain.

Viable (adj.) – able to work successfully or be a good option.

Example: Starting an online business can be a viable way to earn income from home.

Could Eating Less Actually Be Good For You? The Science of Fasting

For most people, eating 3 meals a day is one of the most routine parts of life. However,  a popular trend of intentionally breaking this routine has become extremely popular.  It’s called fasting; almost everyone today has either tried or at least heard of fasting. Essentially, fasting is when you deliberately stop yourself from eating for some amount of time. While it might sound challenging, the health benefits are impossible to ignore.

What Is Fasting?

Fasting is not the same as starving yourself. Starvation is when you are forced to go without

food against your will, often for a long time. Fasting, on the other hand, is a conscious (intentional) choice not to eat for a certain amount of time. People fast for many reasons; some want to lose weight, some want better focus, some do it for religious reasons, and others simply like to suffer (kidding).

Two main types of fasting are popular today. The most common type is called intermittent fasting, which is when you set a schedule of when you are and are not allowed to eat. One of the most common versions is the 16:8 method, which is when you fast for 16 hours and only allow yourself to eat during an 8-hour window. For example, you might decide that you will only eat between noon and 8 pm, after which you cannot eat again until noon the next day. Many people find this surprisingly manageable because a large portion of the fasting window happens while they are asleep. 

The second type is extended fasting, which happens for a much longer period of time, often 48 to 72 hours, although some people even fast for a whole month. While this may sound impossible (and unlike anything a doctor would recommend), it comes with some seriously remarkable health benefits, and they are not just rumors.

Why Do People Fast? The Benefits

One of the most common benefits of fasting might sound a bit counterintuitive. While you might assume that fasting would lead to feeling fatigued, weak, and a bit foggy, most people agree that the opposite is true. Fasting usually makes people feel more alert, mentally sharp, and energized than they usually do.

The reason fasting works so well is that eating food, especially the sugar and carb-loaded food that is ubiquitous today, causes our blood sugar and insulin levels to rise very quickly and then drop suddenly. We often refer to this drop in blood sugar as a “crash,” and it usually leaves us feeling hungry, tired, emotional, and not focused. Therefore, fasting aims to bypass this inevitable crash that comes when we eat.

What happens during a fast is that the body relies on fat as its energy source rather than glycogen (which comes from sugar and carbohydrates). When the body is relying on fat, it is much more stable and allows our brains to work better and faster, making us clear-minded and more productive. 

However, the benefits don't stop there. Fasting also helps us to rebuild our body and stay young by replacing our damaged and aged cells much faster than normal, a process called autophagy. Another benefit is the boost of Brain-Derived Neurotrophic Factor (BDNF) proteins, which improve and fortify the neurons in the brain. The BDNF proteins can actually make us more intelligent and prevent brain disease. Both autophagy and the increase of BDNF proteins happen after about 12 hours, which can be achieved through intermittent fasting.

One major benefit can only come from extended fasting - it’s called stem-cell regeneration. Stem cells are a big topic; they are normally only produced during the fetal stages, which is before we are born. Stem cells can become anything; it's what helps us grow limbs and organs. So when doctors discovered that stem cells can actually be produced again naturally in the body, it was a breakthrough. The benefit is that researchers have observed people with chronic illnesses and diseases being cured from fasting for longer than 72 hours, which is due to stem cell production.

Tips If You Want to Try Fasting

If fasting sounds like something you would like to give a try, here are some practical things to keep in mind:

Drink plenty of water. During a fast, you should aim to drink much more water than normal, at least 2 to 3 liters of water per day. You can also drink coffee and green tea (without milk or sugar), which can help reduce hunger and improve focus.

Eat well before you fast. Focus on nutrient-dense foods, not just breads and junk food. You need a lot of nutrients and minerals to make fasting easier, so many people also try to eat healthier while fasting.

Sleep! Getting quality sleep while fasting is very important. The purpose of fasting is to help our body repair itself and operate better, all of which the body does while asleep. Also, you can avoid late-night food cravings by going to bed early.

Start small. If you have never fasted before, begin with a simple 12-hour overnight fast before attempting anything longer. It will help you gain confidence, and it is also much easier to just skip breakfast or dinner in the beginning than to commit to an intense new eating routine.

For those who want to get healthier, smarter, or just lose some weight, it looks like fasting might be a viable choice.

Conversation Questions

• Had you heard of fasting before reading this article? What did you think of it?

• Do you think it is difficult to skip meals? Why or why not?

• In the article, it says that eating normally may actually be bad for your health. Does this surprise you?

• The article mentions that the brain can function better when you are fasting. Have you ever noticed feeling more or less focused depending on what you have eaten?

• Do you think people in your country eat too many processed foods? Can you give examples?

• What does a typical day of eating look like for you? Do you think it is healthy?

• Dr. Jason Fung argues that the modern diet is very different from how humans ate historically. Do you agree that modern eating habits are a problem?

• The article explains that fasting helps the body "clean itself" through a process called autophagy. Does this change how you think about eating and health?

• Do you think fasting would be easy or difficult for you personally? What would be the biggest challenge?

• Some religions require fasting — for example, Ramadan in Islam or certain periods in Christianity and Buddhism. Do you think religious fasting and health fasting are similar or different?

• Would you ever try intermittent fasting? Why or why not?

• Do you think children should learn about nutrition and fasting in school?

• Is it more important to focus on what you eat or when you eat?

• Do you think people in the future will eat very differently from how we eat today?