There are many different ways to lose weight. One that has become popular in recent years is called intermittent fasting. This is a way of eating that involves regular short-term fasts.

Fasting for short periods helps people eat fewer calories, and also helps optimize some hormones related to weight control. There are several different intermittent fasting methods. Three popular ones are:

The 16/8 Method: Skip breakfast every day and eat during an 8-hour feeding window, such as from 12 noon to 8 pm. Eat-Stop-Eat: Do one or two 24-hour fasts each week, for example by not eating from dinner one day until dinner the next day.

The 5:2 Diet: Only eat 500-600 calories on two days of the week, but eat normally the other 5 days.

As long as you don't compensate by eating much more during the non-fasting periods, then these methods will lead to reduced calorie intake and help you lose weight and belly fat.

-How Intermittent Fasting Affects Your Hormones

Body fat is the body's way of storing energy (calories).

When we don't eat anything, the body changes several things to make the stored energy more accessible.

This has to do with changes in nervous system activity, as well as a major change in several crucial hormones.

Here are some of the things that change in your metabolism when you fast:

Insulin: Insulin increases when we eat. When we fast, insulin decreases dramatically. Lower levels of insulin facilitate fat burning.

Human growth hormone (HGH): Levels of growth hormone may skyrocket during a fast, increasing as much as 5-fold. Growth hormone is a hormone that can aid fat loss and muscle gain, among other things.

Norepinephrine (noradrenaline): The nervous system sends norepinephrine to the fat cells, making them break down body fat into free fatty acids that can be burned for energy.

Interestingly, despite what the 5-6 meals a day proponents would have you believe, short-term fasting may actually increase fat burning.

Two studies have found that fasting for about 48 hours of boosts metabolism by 3.6-14%. However, fasting periods that are longer can suppress metabolism.

-How Intermittent Fasting Affects Your Hormones

Body fat is the body's way of storing energy (calories).

When we don't eat anything, the body changes several things to make the stored energy more accessible.

This has to do with changes in nervous system activity, as well as a major change in several crucial hormones.

Here are some of the things that change in your metabolism when you fast:

Insulin: Insulin increases when we eat. When we fast, insulin decreases dramatically. Lower levels of insulin facilitate fat burning.

Human growth hormone (HGH): Levels of growth hormone may skyrocket during a fast, increasing as much as 5-fold. Growth hormone is a hormone that can aid fat loss and muscle gain, among other things.

Norepinephrine (noradrenaline): The nervous system sends norepinephrine to the fat cells, making them break down body fat into free fatty acids that can be burned for energy.

Interestingly, despite what the 5-6 meals a day proponents would have you believe, short-term fasting may actually increase fat burning.

Two studies have found that fasting for about 48 hours boosts metabolism by 3.6-14% . However, fasting periods that are longer can suppress metabolism.

-Intermittent Fasting Helps You Reduce Calories and Lose Weight

The main reason that intermittent fasting works for weight loss, is that it helps you eat fewer calories.

All of the different protocols involve skipping meals during the fasting periods. Unless you compensate by eating much more during the eating periods, then you will be taking in fewer calories.

According to a recent review study, intermittent fasting can lead to significant weight loss. In this review, intermittent fasting was found to reduce body weight by 3-8% over a period of 3-24 weeks.

When examining the rate of weight loss, people lost about 0.55 pounds (0.25 kg) per week with intermittent fasting, but 1.65 pounds (0.75 kg) per week with alternate-day fasting.

People also lost 4-7% of their waist circumference, indicating that they lost belly fat.

These results are very impressive, and they do show that intermittent fasting can be a useful weight loss aid.

All that being said, the benefits of intermittent fasting go way beyond just weight loss. It also has numerous benefits for metabolic health, and may even help prevent chronic disease and expand lifespan.

Although calorie counting is generally not required when doing intermittent fasting, the weight loss is mostly mediated by an overall reduction in calorie intake.

Studies comparing intermittent fasting and continuous calorie restriction show no difference in weight loss if calories are matched between groups.

Intermittent Fasting May Help You Hold on to Muscle When Dieting

One of the worst side effects of dieting, is that the body tends to burn muscle as well as fat.

Interestingly, there are some studies showing that intermittent fasting may be beneficial for holding on to muscle while losing body fat.

In one review study, intermittent calorie restriction caused a similar amount of weight loss as continuous calorie restriction, but with a much smaller reduction in muscle mass.

In the calorie restriction studies, 25% of the weight lost was muscle mass, compared to only 10% in the intermittent calorie restriction studies.

However, there were some limitations to these studies, so take the findings with a grain of salt.

Intermittent Fasting Makes Healthy Eating Simpler

In my opinion, one of the main benefits of intermittent fasting is the simplicity of it.

I personally do the 16/8 method, where I only eat during a certain "feeding window" each day.

Instead of eating 3+ meals per day, I eat only 2, which makes it a lot easier and simpler to maintain my healthy lifestyle.

The single best "diet" for you is the one you can stick to in the long run. If intermittent fasting makes it easier for you to stick to a healthy diet, then this has obvious benefits for long-term health and weight maintenance.

-How to Succeed With an Intermittent Fasting Protocol

There are several things you need to keep in mind if you want to lose weight with intermittent fasting:

Food quality: The foods you eat are still important. Try to eat mostly whole, single ingredient foods.

Calories: Calories still count. Try to eat "normally" during the non-fasting periods, not so much that you compensate for the calories you missed by fasting.

Consistency: Same as with any other weight loss method, you need to stick with it for an extended period of time if you want it to work.

Patience: It can take your body some time to adapt to an intermittent fasting protocol. Try to be consistent with your meal schedule and it will get easier.

Most of the popular intermittent fasting protocols also recommend strength training. This is very important if you want to burn mostly body fat while holding on to muscle.

In the beginning, calorie counting is generally not required with intermittent fasting. However, if your weight loss stalls then calorie counting can be a usefulness

Fasting is an age-old practice, often done for religious reasons, but fasting for weight loss is still capturing the public imagination. You can find dozens of do-it-yourself plans touting the unproven benefits of fasting, ranging from flushing "poisons" from the body to purging 30 pounds of fat in 30 days

It's true that fasting -- that is, eating little to no food -- will result in weight loss, at least in the short term. But the risks far outweigh any benefits, and ultimately, fasting can cause more harm than good.

-Typical Fasting Weight Loss Plans

Fasting regimens vary, but the basic premise usually starts with a strict regimen allowing only water, juice and/or some kind of laxative concoction. Some plans allow a few solid foods, but are still called fasts because they provide so few calories.

Not all fasts are created equal. Some can be perfectly safe, such as medical fasts supervised by a physician. Religious and cultural fasts are typically undertaken as an act of devotion, last from 24-48 hours, and are not intended to promote weight loss.

Fasts lasting a day or two are unlikely to be dangerous for most healthy adults. But high-risk people, the elderly, anyone with a chronic disease, pregnant women, and children are advised against any type of fasting.

The real danger lies in staying on the fast for prolonged periods, anywhere from three days to a month.

-Dangers of Fasting for Weight Loss

When you dramatically reduce your calorie intake, you will lose weight. But it can also cause all kinds of health problems, including muscle loss. Further, when you start fasting, your body goes into conservation mode, burning calories more slowly.

Keep in mind that the initial weight lost on a fast is primarily fluid or "water weight," not fat. And when you go back to eating, any lost weight usually gets a return ticket back. Not only do most people regain weight lost on a fast, they tend to add a few extra pounds because a slower metabolism makes it easier to gain weight. Worse, the weight that is regained is likely to be all fat -- lost muscle has to be added back at the gym.

Side effects of fasting include dizziness, headaches, low blood sugar, muscle aches, weakness, and fatigue. Prolonged fasting can lead to anemia, a weakened immune system, liver and kidney problems, and irregular heartbeat. Fasting can also result in vitamin and mineral deficiencies, muscle breakdown, and diarrhea. When you drink laxative concoctions during a fast, there is an increased risk of fluid imbalance and dehydration.

The risks get more complicated and severe the longer you stay on a fast, or if you repeatedly go on fasts.