Fasting has been in practice for centuries all over the world. Limiting or completely eliminating food for a certain period of time is more natural than many of us imagine. Even so, questions still remain regarding fasting and the effects it can have on your health.
Is fasting good for you? There have been numerous studies conducted on the effects of fasting on your health. Evidence has been found that fasting can improve overall health, including heart health and immune system function. However, fasting isn’t for everyone and may not always result in the benefits you are hoping for.
If you’re on the fence about incorporating fasting into your lifestyle, read below to learn more about the potential benefits and side effects that could come along with it.
Different Types of Fasting
There is no set structure to fasting that everyone follows. The ways you can fast are only limited by your own imagination. As long as you are abstaining from food for a period of time, you’re technically fasting.
Some people only do occasional fasting. They eat normally most of the time, but every so often they decide to spend anywhere from 12 to 24 hours fasting. There’s no plan set in place. It all comes down to convenience.

However, there are proofs showing some types of fasting is more effective than others. Despite that most studies shows that fasting can lead to positive results such as boosted metabolism, brain stimulation and weight loss, there are potential negative consequences that must to be taken into consideration.
With that being said, choosing a good fasting method can make some differences.
Effective Fasting methods include:
- Several versions of 24-hour fasting
- Whole-day fasting
- Several versions of intermittent fasting
One of the most popular kinds of fasting today is intermittent fasting. You can hardly read anything related to fasting without this term coming up. It’s become a big hit because many people claim it works. Look online, and you’ll find a seemingly countless number of positive testimonials about it.
What Is Intermittent Fasting?
Intermittent fasting is defined as a recurring pattern of fasting where you spend a certain period of time eating normally and then a certain period of time fasting. Unlike a spur of the moment fast, intermittent fasting is set on a schedule.

Types of Intermittent Fasting:
- 16/8 Method
- Alternate Day Fasting
- 5:2 Fasting
- Eat-Stop-Eat
- The Warrior Diet
The 16/8 method of intermittent fasting is one of the most used variations. It is also called time-restricted fasting because you can tweak it to meet your needs.
This kind of fasting works by separating your day into 8-10 hours of eating time and 14-16 hours of fasting.
Alternate day fasting is another extremely popular form of intermittent fasting. With this method, you would normally eat for one day and then fast the next day.
However, instead of a full fast, you simply limit your calories to around 500 on fasting days.
With 5:2 fasting, you are splitting your week into normal and fasting days. For 5 days a week, you eat normally.
On the remaining 2 days, you only consume 500-600 calories. These small bursts of fasting can fall on any 2 days of your choosing.
The eat-stop-eat method is similar to the 5:2 method of fasting, but the fasting days are complete fasts. On either 1 or 2 days during the week, you would fast for a full 24 hours.
This method isn’t the easiest. 24 hours of fasting can be rough on the body.
The Warrior Diet was at the forefront of popularizing a type of intermittent fasting. During this diet, you only eat small amounts of fruits and vegetables all day long.
Then, at night, you consume one huge meal within a 4-hour period.

The Results of Fasting in Your Body
After you finish eating, your body uses glucose for energy. This is a normal process that happens every day when you’re eating normally.
The point of fasting is to make it to a point where there is no more glucose to burn, so your body switches to using stored fats instead.
The true results of fasting begin around 6-8 hours after the last time you eat. That’s when you start to feel the most hungry and tired and even irritated. The longer you draw out the fast, the more intense the effects of it become.
After a few days of fasting, your body may enter a state called Ketosis. This process forces your body to use fat for energy rather than other means, aiding in weight loss and providing other health benefits.
Important note: Prolonged fasting isn’t recommended without seeking advice from a medical professional first. Going long periods of time without food, such as a juice fast, can cause harmful effects on the body.
The Health Benefits of Fasting
While fasting is still a hotly debated topic, there have been several studies done over the years on the benefits it has on your health.
There are many proven claims of positive things that can be achieved through fasting, especially intermittent fasting.
Let’s take a look at what you can potentially gain through fasting.
1. Improved Heart Health
Heart health is a huge issue in today’s world, and there are significant findings to suggest that fasting can decrease the risk of heart disease.
Several studies, such as this one, have been done that show fasting has a dramatic effect on reducing the level of triglycerides and bad cholesterol in the body. It can even lower these things by up to 30%.

There is also evidence to suggest that fasting reduces your risk of developing coronary artery disease. It’s hard to argue that fasting isn’t beneficial to the health of your cardiovascular system.
2. Greater Insulin Sensitivity
Intermittent fasting can be a powerful tool in preventing sudden spikes and crashes in blood sugar levels. Keeping your blood sugar steady is especially important for people who are at a greater risk for developing Type 2 Diabetes.
Raising your body’s natural sensitivity to insulin through fasting helps it to move glucose from your bloodstream to your cells much more efficiently.
This can keep your pancreas from overloading on how much insulin it makes, preventing it from wearing out entirely.
Despite these benefits, there have been some studies that suggested these effects could be different in women than they are in men.
This study found that alternate-day fasting actually impaired blood sugar control in women rather than improving it.
3. Help with Inflammation
Inflammation is normal in the body to help in fighting off illnesses. For some people suffering from conditions such as heart disease and arthritis, chronic inflammation can be a big part of the problem.

Research has provided a lot of evidence pointing to the benefits of fasting on inflammation. It has proven in study after study to decrease the level of inflammation, improving health overall.
This connection to reducing inflammation is a big key to the benefits of fasting when it comes to your health. It has a connection to many of the other benefits on this list, making it one of the most important of them.
4. Boost in Brain Function
By fasting, you may be increasing the level of brain functioning while also protecting it against certain degenerative diseases.
Your brain can become overactive after eating, using the energy provided to go into overdrive.
During fasting, your body is placed in a much more conservative setting. Energy reserves are low, and your brain must slow down and focus on being efficient.
There have been studies in animals that show the positive effects on the brain-derived from fasting.
This study on mice shows improved brain function in mice after extended intermittent fasting. Others have shown that fasting can promote the growth of new nerve cells in the brain.

The effect of fasting on inflammation connects to the possibility that fasting can protect your brain against degenerative diseases like Alzheimer’s and Parkinson’s. There is also some evidence that indicates it might improve life for people already suffering from these diseases.
Research into the benefits of fasting for the brain are still early and limited, but the results so far are promising.
5. Immune System Support
Greater cell regeneration associated with fasting can greatly improve the function of your immune system. Abstaining from food when you’re suffering from an illness can benefit your body a lot more than eating because of this.
The effects on certain immune cells in mice during intermittent fasting were shown in one study to be incredibly beneficial.
The cells seemed to become optimized by the fasting and were better able to clear the body of a familiar infection than mice who weren’t fasting.
Because fasting is linked to reduced inflammation, it also has a promising outlook for people suffering from immune disorders.
Many doctors have noticed that periods of fasting seem to improve such people’s conditions, noting that they seem to look and feel healthier.
6. A Helping Hand Against Cancer
Because fasting is connected to higher metabolism and immune system function, there is a link between fasting and helping to prevent the formation of cancer in the body. Fasting has also shown promising effects on the treatment of cancer cells.

There have been studies conducted on mice and on cancer cells in test tubes that show the effectiveness of fasting in preventing tumor growth. It may even be just as effective in preventing growth as chemotherapy.
For people undergoing chemotherapy, fasting can reduce the severity of their side effects. It may even work with chemotherapy in preventing further formation of cancer in the cells.
7. Promotion of a Longer Life
You may not believe this but fasting has been linked to delayed aging and increased longevity.
Research shows that fasting increases how much human growth hormone your body makes. This hormone is linked to growth, metabolism, and muscle strength, all of which help delay the effects of aging.
As you age, your metabolism slows, and your muscles begin to deteriorate. Increasing your natural level of human growth hormone can help in limiting these effects and keep you feeling younger and healthy later into life.
During fasting, your body also triggers a process in the body that breaks down old cellular material, which builds up more as you age.
Though the evidence of fasting leading to a longer life span is still in the early stages, there are promising results popping up in animal studies.
This study on mice showed that the mice who were only fed every other day had a lifespan 83% longer than mice who were fed every day.
Fasting and Weight Loss
No matter the benefits that fasting has on your health, the most popular reason for fasting is for dietary reasons.
Cutting out food for a period of time is a tried and true method to drop some unwanted pounds. That’s why it’s included as a part of many different diets.

Fasting is one of the most popular ways to lose weight, and one of the most effective. There’s a good reason that it’s used by so many people to lose and manage their weight over long periods of time. It can even be more effective than other forms of dieting.
The reason fasting works so well for weight loss is the fact that it forces your body to use up fat stores in your body for energy when it runs out of food. This usually happens around 6 hours after you begin your fast.
How to Fast for Weight Loss
Incorporating a form of intermittent fasting is a great way to continually manage your weight without worrying about it all coming back when your diet is done.
It is more of a lifestyle change than a diet, making it more effective over a longer period of time due to the increase in your metabolism.
While prolonged fasting is good for fast weight loss, it also comes with more complications. Fasting for days at a time will certainly help you drop weight, but it often isn’t permanent.
The weight you lost during your fast will usually return as soon as you go back to eating normally.
The Effects of Ketosis on Your Body
While ketosis is usually associated with a ketogenic diet, it can also be achieved through prolonged fasting. If you eat fewer than 50 grams of carbs a day for 2-4 days, your body will more than likely enter ketosis.
Ketosis is a process in the body where energy typically derived from carbs comes from ketones instead.
These ketones are produced from fat in the body. This makes ketosis an ideal state for weight loss, as well as providing other benefits to your health.

The health benefits associated with ketosis are much the same as the health benefits of fasting. There have been studies conducted that show evidence that a state of ketosis can lead to things such as:
- Lower risk of heart disease
- Prevent or improve the effects of Type 2 Diabetes
- Improve the symptoms of neurodegenerative disorders such as Alzheimer’s and Parkinson’s
- Aid in fighting cancer
Though ketosis is safe and even good for healthy people, it may make you feel a bit sick in the beginning. You may experience headaches, fatigue, and constipation in the early days, but these symptoms should subside.
Potential Dangers of Fasting & Who Shouldn’t Fast?
In certain situations, fasting can do more harm than good. Intermittent fasting can be detrimental for some people, even with all the benefits it shows. Fasting can lead to dehydration, an increase in stress levels, disrupted sleep, and headaches.
You Should Not Start Fasting If:
- You are taking medication that requires food
- You suffer from malnutrition
- You have a metabolic disorder
- You are pregnant
- You are under 18
- You are at risk for developing an eating disorder
Fasting isn’t well-suited to everyone. If you have concerns about whether or not fasting is right for you, you should consult a medical professional before starting. If you notice any adverse effects during fasting periods, it’s best to stop until you can get professional medical advice.

What You Should and Shouldn’t Do When Fasting
If you are serious about fasting, you should know how to go about it in a way that is safe and healthy.
Everyone’s body is different, but there are a few good rules you should follow while fasting to get the most out of it. Your health should always come first.
What to Do When You Are Fasting:
Do make sure fasting fits your lifestyle. You should be ready and willing to take on fasting as a lifestyle change. It’s best to begin fasting when you aren’t experiencing a great level of stress in your life. It could only add more stress on top of the rest.
Do keep yourself distracted. Fasting is made much easier when you aren’t thinking about how long it is until you can eat again. You should do things that you enjoy, treat yourself to something new, or just go for a walk to keep your mind occupied.
Do drink plenty of water. Dehydration isn’t fun and should be avoided at all costs while fasting. You will lose 20-30% of your normal water intake while fasting, so it’s essential to replace it by drinking plenty of water on fasting days.

Do inform your doctor of your fast. This is especially true if you have any concerns about the effects it will have on your health. Even something like low blood sugar can cause you to have an adverse reaction to a fast.
Do ask for help. If you feel like you’re going crazy, reaching out to friends and family is a great way to keep you on track. It’s even better if you can find someone that’s willing to do the fast with you. Even an online support group can make the hours easier.
What Not to Do When You Are Fasting
Don’t fast if you aren’t fit for it. People who fall into the category of avoiding fasts are people who are pregnant, young kids, and those on time-sensitive medication. Fasting can be hard on the body and could present dangers to those who are already compromised in some way.
Don’t feast right before a fast. Eating a large amount of food just before a fast won’t help your energy levels. You may end up feeling even worse. It’s best to eat a meal that is well-balanced and includes protein and a carb like a starchy vegetable.
Don’t engage in any high-intensity exercise while fasting. You should limit yourself to light exercise on fasting days to avoid burning up all your energy. If you do something intense, you may end up ruining your fast or harming your body in the process.
Don’t forget to take your vitamins. Some vitamins can only be taken with food, while others should be taken on an empty stomach. Keeping up with your nutrients is important during a fast so that your body doesn’t become deficient in anything.

Don’t binge after a fast. While it’s incredibly tempting, you shouldn’t have a feast after you’ve finished fasting. There are better ways to celebrate your success. Instead, have a healthy, well-balanced meal and pat yourself on the back.
Tips for Fasting Safely
Fasting, like most major lifestyle changes, should be carried out properly to avoid any serious complications. To get any benefits from your fast, you need to do it safely. The following tips will help you stay out of the danger zone.
1. Start Out Small
It’s not easy to go from a normal eating schedule to a full-blown fast at the snap of your fingers. Sometimes, it’s best to gradually ease your way into it. Especially if you plan to fast for long periods of time, you want your body to be prepared.
At first, you can still incorporate some food into your fasting periods. Some forms of fasting allow you to eat around 500-600 calories on fasting days, which keeps your body from being entirely shocked by the lack of food.
Intermittent fasting is a great way to start out your fasting journey, as the fasting periods are much shorter than fasts that last full or multiple days.
Start by setting aside a certain number of hours in the day to fast. 12 is the best place to start.
When you are fasting, it’s also a good idea to keep exercise to a minimum. Going for walks and doing yoga are all acceptable ways to keep yourself active when you have no food in your system. Try not to use up too much energy.

2. Hydration Is Crucial
Dehydration is a very real danger associated with fasting. Your body gets some of its water supply from food, and you’re taking that away for a while. It’s essential that you replace the water you’re missing out on during your fast.
You should be drinking no less than 8 cups of water a day, especially on fasting days. Listening to your body is key.
Mild dehydration may cause headaches, dizziness, and thirst. If you start to notice you’re feeling thirsty, drink some water.
3. Protein Is Your Best Friend
Fasting eats up your body’s fat, but it can also turn on your muscles as well. To avoid losing muscle mass during fasts, you should incorporate plenty of protein into your diet on days when you eat.
Additionally, if you are eating a small amount on fasting days, protein can drastically improve any side effects. A meal made up of 30% protein can do incredible work at reducing your appetite, making the fast easier to complete.

4. Supplement Your Fast with Vitamins
Restricting your calorie intake in any way runs the risk of depriving your body of essential nutrients. One way you can combat this is by taking vitamins while doing your fast. Even a good multivitamin could do you wonders.
Make sure to check the instructions for any vitamins you decide to take. Some vitamins are meant to be taken with food and could make you feel sick if you take them on an empty stomach. Taking them during eating periods may be the best option.
5. End Your Fast If Necessary
During a fast, listening to your body is one of the most important things you can do. Sometimes, a fast just isn’t working out, even if it has before. Battling your way through sickness may only make things worse.
Stop Fasting If Your Experience:
- Dizziness
- Nausea and Vomiting
- Diarrhea
- Loss of Consciousness
- Burning in the Stomach
- Chest Pain
- Stomach Pain

Feeling hungry, fatigued, or irritated are common during fasting and aren’t serious symptoms. Most of the time, these will pass.
However, if you begin to show more serious signs of illness, you should end your fast right away until you regain your energy.
Fasting Is a Natural Process
If you think about it, most of us already fast every single night. Sleeping for a healthy period of time provides you with a short 8 hour fast that is normally ended at breakfast time. While these small fasts aren’t long enough to be highly beneficial, they are still a form of fasting.
Fasting has been on the rise as a way to lose weight and improve health for years. The studies of all the benefits that can come from fasting are a great support for the popularity of fasting as more than just a fad.
Weight loss, reduced risk of disease, improvement of chronic disease symptoms, and the delay of the effects of aging give you very good reason to include fasting in your life.
It’s not suitable for everyone, but you can’t deny that it has the potential to be very good for you.