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Intermittent Fasting: Benefits & How Does It Work?

Mitchelle Morgan

Updated on - Written by
Medically reviewed by Kathy Shattler, MS, RDN

benefits of intermittent fasting

Weight loss is essential for the health and well-being of every person. However, it’s important to find healthy and safe ways to lose weight. One way to gain these many health benefits is intermittent fasting (IF).

While taking part in intermittent fasting, you eat healthy foods during the eating window. There is also a fasting window where you don’t take in any food. The eating window allows you to maintain a healthy diet and shed excess weight while improving overall health.

Other health benefits of intermittent fasting include reducing insulin resistance, oxidative stress, and inflammation. IF also lowers the risk factors of heart disease, induces cellular repair process, and improves brain health. 

Let’s find out more about IF.

What is Intermittent Fasting?

Intermittent fasting is an eating pattern that guides you on what time to eat and when to start the fasting duration. Intermittent fasting isn’t a restrictive diet pattern since it doesn’t dictate what foods to eat during the eating window. But, it’s essential to have an eating plan that consists of healthy foods.

Fasting has been around for centuries, and it’s a practice that many people still engage in. Intermittent fasting involves a fasting period where you can’t eat any food even if you feel hungry. The benefits of fasting can help you overcome[1] some health problems such as obesity, cardiovascular disease, and even some cancers.

Intermittent fasting focuses on the eating period.

Below are 5 IF plans that you can work with:

The 5:2 Diet

The 5:2 Diet involves normal eating 5 days a week. However, for the remaining 2, you have to restrict your calorie intake to below 600gm.

Time-Restricted Eating

This eating pattern means you have to fast for 12 hours 7 days a week. You can even fast for longer periods and eat the remaining time. One of the most popular time-restricted eating patterns is 16/8. 

You fast for 16 hours in a day and eat for 8 hours, allowing you to eat 2 to 3 meals.

Alternate-Day Fasting

With alternate-day fasting, you eat today and skip meals the next day. It requires skipping calorie intake every other day.

Eat Stop Eat

In a week with 7 days, you have to fast for 1 or 2 days. Fasting lasts 24 hours, after which you can eat.

The Warrior Diet

In intermittent fasting, you can work with the Warrior Diet. This involves eating small portions of raw vegetables and fruits during the day. At night, you can have one large meal. 

How Does It Work?

IF works to reduce body fat and leave you healthier. Excess body fat can cause numerous health problems like poor cardiovascular health. However, with fasting, some changes start to happen in your body.

Intermittent fasting affects your body’s cells and molecules, making it possible to utilize body fat. The process happens when certain hormones[2] like HGH (Human Growth Hormone) increase in the body. Thus IF may aid with fat reduction[3] and better cholesterol levels.

At the same time, your overall health improves when cellular repair begins. Autophagy, the body’s way of cleaning out damaged cells, begins when bad cells and old proteins are removed during this period. In their place are better cells that benefit the human body.

As these changes take place, your body needs energy. Your body burns fat since there’s less glycogen intake hence low blood sugar levels may occur. When the body burns fat, you start to notice a weight reduction.

When you pick an eating pattern, it requires lowering your calorie intake for a specific period. The body begins to use fat stored in cells as fuel, so even when you eat, you burn the fat instead of storing it in your body. 

For example, in the 16/8 IF regimen you abstain from food for 16 hours and eat in the 8 hours window. Intermittent fasting works when you restrict eating food during the fasting window, but drinking water is essential. Hydration helps your body[4] in many ways. Plus, there are other fluids like plain coffee and coconut water that you can take.

Fasting benefits the body in many ways, but you must be cautious if you suffer from eating disorders. If you have eating disorders, it is best to consult with a Registered Dietitian before engaging in this type of diet. A combined behavioral approach may be the best route to take in this case.

What are the Health Benefits of Intermittent Fasting?

There are many health benefits of intermittent fasting worth noting.

1.     Weight Loss

For many people, weight loss[5] is a huge motivation for taking part in intermittent fasting since your body gets to burn fat. Since you’re fasting for certain hours in a day, you eat less food. As a result, you eat fewer calories and have the chance to incorporate healthy fats and other good food into meals when you are in your eating window. Don’t forget to hydrate during your fasting window.

In addition, the body secretes hormones that help you lose weight while lowering blood sugar levels. An increase in human growth hormone levels will help your body get rid of harmful fat. You need an eating plan and stick to a specific intermittent fasting cycle for this to happen.

Intermittent fasting leads to loss of weight which has numerous health benefits, including lower insulin levels and increased insulin sensitivity. Also, you have a better metabolic rate, making it possible to burn more calories each day. IF allows your gastrointestinal system to rest and burn fat for fuel rather than storing it.

Fasting causes fat loss, which is important, especially if you have visceral fat. Having fat around the stomach[6] can lead to health issues like cardiovascular illnesses and diabetes, among other diseases. Fasting makes it possible to lose more abdominal weight and this is accelerated by incorporating an exercise routine into your fasting cycles. Weight loss improves your inward appearance, not just how you look on the outside. Having a better body image[7] is great for your mental health and general well-being. Plus, you get more confidence and can live a more productive life every day.

2.     Reduction of Insulin Resistance

Insulin intolerance puts you at risk of getting type 2 diabetes because of high blood sugar levels. The good news is intermittent fasting can help tackle[8] insulin intolerance by lowering sugar levels.

People with high-risk factors for type 2 diabetes can benefit from IF. A study[9] done on diabetic mice involved periods of IF. The results showed that intermittent fasting helped improve the mice’s chance of survival. Also, they were at a lower risk of getting diabetic retinopathy.

In another study[10], a group of people took part in intermittent fasting to prevent type 2 diabetes. The researchers noted that 12 weeks of fasting led to the reduction of blood sugar by up to 6%. Insulin was also lowered by up to 31%.

3.     Fight Inflammation and Reduce Oxidative Stress

A fasting diet can help you lower inflammation in the body. Inflammation is vital since it helps the body heal itself. However, cases of chronic inflammation[11] can lead to lots of discomfort and pain. Chronic diseases like heart disease, diabetes, high blood pressure (BP), and cancer can cause chronic inflammation.

IF can help fight inflammation in the body. It’s possible when you eat specific foods during the eating period. Food like vegetables, fruits, healthy fats, fatty fish, and nuts are excellent when fighting inflammation[12] in the body. Many of these are lower-calorie food options as well. Apart from fighting inflammation, IF can reduce oxidative stress, which involves free radicals. These are unstable molecules[13] that react with DNA and protein causing damage. There’s a study[14] that shows intermittent fasting can help reduce oxidative stress in the body.

4.     Reduce Poor Heart Health Risk Factors

Having lots of fat in the body and high cholesterol levels puts you at risk of heart disease and high BP. Currently, cardiovascular problems are a leading cause of mortality[15] worldwide. This is because of certain factors that increase the probability of heart disease, such as-

  • Presence of bad cholesterol (low-density lipoproteins or LDL)
  • High blood pressure
  •  Chronic inflammation
  • High blood sugar levels

There’s more need for research on the benefits of IF on heart health. However, losing weight[16] is crucial for getting rid of bad cholesterol.

5.     Improve Brain Health

Among the benefits of IF is better brain health. As the body’s health improves, so does the brain. Intermittent fasting helps your body with oxidative stress, chronic inflammation, and insulin resistance.

A study[17] done on mice showed that intermittent fasting is good for brain health. This happens when fasting facilitates the growth of new nerve cells.

In addition, you experience an increase in BDNF (Brain-Derived Neurotrophic Factor), a brain hormone. When you have a deficiency of BDNF, you may experience mental health problems such as depression[18].

6.     May Prevent Alzheimer’s Disease

Among the worst chronic illnesses is Alzheimer’s, a neurodegenerative disease. It has no cure, so it’s best to find prevention methods. A study[19] done on rats showed that IF may slow down the onset of Alzheimer’s.

But, there’s still a need for more human studies to show the benefits of IF on Alzheimer’s patients.

7.     Help You Live Longer

There are many health benefits of intermittent fasting for women. Among the top motivations for people choosing to fast is to live longer. IF helps to extend your lifespan[20] and also slow down aging. As you fast, you are on a calorie restriction, which affects the health and longevity of mitochondria, the powerhouse of the cell. A decrease in the health of mitochondria leads to aging-related diseases. In a study[21] done on rats, the researchers had them on alternate days fasting. This led to rats that took part in IF living 83% longer than those that didn’t. In another study[22], some mice took part in fasting, and they had a 13% increase in their lifespan.

Fasting benefits the body by reducing the onset of illnesses and other conditions that lower the lifespan of living things. Aging leads to the body experiencing lots of changes that can increase the rate of mortality. However, you can experience cell regeneration and overall better health with IF.

The Bottomline

Intermittent fasting involves periods of fasting and eating. You can’t eat any food during the fasting period, even when you feel hungry. This helps start processes that cause the body to burn fat. When you experience fat loss, you can enjoy numerous health benefits.

Having fat in the body, especially visceral fat, can lead to health issues like chronic diseases. One of the best ways to prevent this is weight loss through intermittent fasting.

As a result, you can enjoy the health benefits of intermittent fasting like a healthy heart, less oxidative stress and inflammation, and other health benefits like better brain health. While you won’t eat during the fasting, drinking water is crucial. All in all, consult a doctor for guidance before starting IF


+ 22 sources

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Mitchelle Morgan

Medically reviewed by:

Kathy Shattler

Mitchelle Morgan is a health and wellness writer with over 10 years of experience. She holds a Master's in Communication. Her mission is to provide readers with information that helps them live a better lifestyle. All her work is backed by scientific evidence to ensure readers get valuable and actionable content.

Medically reviewed by:

Kathy Shattler

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