IF: The Complete Idiot’s Guide for Newbies
Explained: What It Is, How It Works, and What It Does
Weight-Reducing Advantages
Less Complicated Way of Life
Why Wouldn’t They?
In Case You Had Any Questions About Potential Dangers
Should You Jump Right In?
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Fasting at specific times of the day, or “intermittent fasting,” is a popular way to diet. There’s evidence to suggest it could boost your mental and cardiovascular health in addition to helping you trim down.

Presently, intermittent fasting (IF) is one of the most well-liked approaches to health and fitness all over the globe.

People are adopting it as a means to slim down, get healthier, and streamline their routines.

Several studies show that it has beneficial effects on your body and brain, and it may even extend your life (1Trusted Source, 2Trusted Source, 3Trusted Source).

If you’re new to intermittent fasting, you won’t find a better resource than this.

Photographed by Aya Brackett
How Does IF Work?
Fasting for extended periods of time and then eating normally again is known as intermittent fasting (IF).

It doesn’t tell you what to eat, just when to eat it.

In this regard, it is more accurately referred to as an eating pattern than a diet.

Fasting for 16 hours once a day or for 24 hours twice a week are two examples of common intermittent fasting schedules.

As a species, we evolved with the practice of fasting. There were no such things as supermarkets, refrigerators, or year-round availability of food for ancient hunter-gatherers. There would be times when they would have nothing to eat.

As a result, our species adapted to go for days, even weeks, without eating.

In fact, intermittent fasting is more physiologically appropriate than the constant consumption of three to four meals per day.

Fasting is practiced for religious and spiritual purposes in many religions and cultures, including but not limited to Islam, Christianity, Judaism, and Buddhism.

Fasting for extended periods of time and then eating normally again is known as intermittent fasting (IF). It’s currently very popular in the health and fitness community.

Methods of Intermittent Fasting
Alternating periods of eating and fasting throughout the day or week is one of the most common forms of intermittent fasting, though there are many other variations.

For the duration of the fasting periods, you consume either a very small amount of food or none at all.

The most common approaches are:

The 16/8 approach, also known as the Leangains protocol, entails skipping breakfast and limiting daily eating to an 8-hour window, such as 1-9 p.m. After that, you’ll need to go without food for 16 consecutive hours.
Eat-Stop-Eat is a method of intermittent fasting in which you go without food for 24 consecutive hours once or twice a week.
The 5:2 diet Two days out of the week, you eat very little (between 500 and 600 calories) while the other five days you eat normally.
Weight loss should result from any of these strategies because they all reduce calorie intake, provided that you don’t make up for it during the eating windows.

The 16/8 approach is popular because it is thought to be the least complicated, longest-lasting, and least difficult to maintain. Furthermore, it is the most widely used.

SUMMARY Intermittent fasting can be carried out in a number of distinct fashions. Each of them consists of alternating periods of eating and fasting throughout the day or week.

The Impact on Your Body’s Hormones and Cells
Several physiological changes occur at the cellular and molecular levels during a fast.

Your body may alter hormone levels, for instance, to facilitate easier access to fat reserves.

Furthermore, your cells start crucial repair processes and can alter gene expression.

When you fast, your body goes through the following changes:

The growth hormone levels in the body can increase by as much as five times when HGH is administered. Numerous health and fitness goals, including weight loss and muscle gain, can be advanced by doing this (4Trusted Source, 5Trusted Source, 6Trusted Source, 7Trusted Source).
Improvements in insulin sensitivity coincide with a precipitous decrease in fasting insulin concentrations. Increased access to fat stores occurs at lower insulin levels (8Trusted Source).
When you go without food for an extended period of time, your cells begin a repair process. Included in this category is autophagy, a process by which cells eat and dispose of their own old, broken proteins (9Trusted Source, 10Trusted Source)
Alterations in gene expression: variants in genes involved in longevity and disease resistance (11Trusted Source, 12Trusted Source).
The health benefits of intermittent fasting can be traced back to the aforementioned changes in hormone levels, cell function, and gene expression.

Human growth hormone increases and insulin decreases during fasting. The cells in your body can alter gene expression and kick off crucial cellular repair processes.

A Highly Effective Means of Slimming Down
The majority of people who try intermittent fasting do so in an effort to lose weight (13Trusted Source).

Intermittent fasting can help you lose weight simply by requiring you to eat fewer meals per day.

The use of a fasting schedule with defined “feeding” windows can boost the effectiveness of weight loss by regulating hormone levels.

Norepinephrine, a fat-burning hormone, is released at a higher rate, which complements the decrease in insulin and increase in growth hormone (noradrenaline).

As a result of these hormonal shifts, short-term fasting has been shown to boost metabolic rate by 3.6-14%. (14Trusted Source, 15Trusted Source).

Intermittent fasting causes weight loss by adjusting both the number of calories consumed and burned.

Intermittent fasting has been shown to be an effective method of weight loss.

When compared to other studies on weight loss, the 3-8% weight loss that can be achieved following this eating plan in just 3-24 weeks is striking (1).

Also, participants lost an average of 4.7 inches from their waist size, a significant amount of the dangerous belly fat that collects around your organs and increases your risk of disease, as reported in the same study (1).

Another study conducted in 2011 found that compared to the conventional method of continuous calorie restriction, intermittent fasting results in less muscle loss (16Trusted Source).

Keep in mind that the main reason it works is because it encourages you to consume fewer calories on a daily basis. You might not lose any weight at all if you eat excessively during your eating windows.

Fasting at irregular intervals can help you lose weight by reducing your calorie intake. You can expect to lose weight and abdominal fat quickly and easily by doing this.

Health Advantages
Intermittent fasting has been the subject of numerous studies in both animals and humans.

Evidence from these studies suggests that it may have significant effects on both weight management and general physical and mental well-being. Potentially, it can extend your life.

Health-wise, intermittent fasting has many advantages, including the following:

As was previously mentioned, intermittent fasting can aid in weight loss and the reduction of belly fat without the need for strict calorie counting (1Trusted Source, 13Trusted Source).
Type 2 diabetes risk can be mitigated by intermittent fasting due to its effect on insulin resistance, which results in a 3-6% drop in blood sugar and a 20-31% rise in fasting insulin (1).
Some research has shown a decrease in inflammatory markers, a major contributor to many chronic diseases (17Trusted Source).
Heart health: Intermittent fasting has been shown to lower cardiovascular risk factors such as “bad” LDL cholesterol, blood triglycerides, inflammatory markers, blood sugar, and insulin resistance (20Trusted Source).
Cancer: Intermittent fasting has shown promise in animal studies for reducing cancer risk (22Trusted Source, 23Trusted Source, 24Trusted Source, 25Trusted Source).
The brain hormone BDNF is increased during intermittent fasting, which may help promote new nerve cell growth. Perhaps it can even prevent Alzheimer’s (26Trusted Source, 27Trusted Source, 28Trusted Source, 29Trusted Source).
Intermittent fasting has anti-aging benefits and can increase rat lifespan. Rats that went without food for 36 hours had a 36-83% longer lifespan than those who ate normally (30, 31).
Consider that study is still in its preliminary stages. Small, short-term, or animal studies dominated. Higher quality human studies still have many questions to answer (32Trusted Source).

There are many potential health benefits to intermittent fasting, especially for the brain and body. There is some evidence that it can help people lose weight and thereby lower their risk of developing diabetes type 2, cardiovascular disease, and cancer. It could also increase your longevity.


Increasing Your Viewing of Healthy Lifestyle Shows Simpler
Eating well is easy to do, but it’s not always easy to stick with.

The time investment needed to prepare nutritious meals is a major barrier.

If you’re planning on doing intermittent fasting, you may find that it simplifies your life by reducing the number of meals you need to prepare, cook, and clean up after.

The health benefits and time savings of intermittent fasting have made it a hit among the “life-hacking” community.

CONCLUSION Intermittent fasting is advantageous because it simplifies the process of eating healthily. With fewer meals to make, cook, and clean up after, your workload is reduced.

Who Ought to Exercise Caution?
Of course, not everyone can or should practice intermittent fasting.

Fasting should not be attempted by anyone who is underweight or who has a history of eating disorders without first seeking advice from a medical professional.

Especially in these circumstances, it may even be harmful.

Do Women Need to Fast?
Some research suggests that women may not reap the same health benefits from intermittent fasting as men.

One study from 2005 found that while it increased insulin sensitivity in men, it decreased it in women, leading to worse blood sugar control in women (33Trusted Source).

While there are no available studies on the effects of intermittent fasting on fertility in humans, studies conducted on rats have shown that it can lead to emaciation, masculinization, infertility, and missed cycles in female rats (34Trusted Source, 35Trusted Source).

Several anecdotal reports have surfaced of women whose menstrual periods having stopped when they began intermittent fasting and returning to normal when they went back to their previous eating pattern.

Because of these concerns, women should use caution when intermittent fasting.

Different rules, such as starting slowly and stopping cold turkey if symptoms like amenorrhea appear, apply to these individuals (absence of menstruation).

Put off intermittent fasting for the time being if you’re having fertility problems or trying to conceive. If you are expecting or nursing, you should probably avoid this diet as well.

SUMMARY Those with a history of eating disorders or who are underweight should not fast. It has also been suggested that intermittent fasting may have negative effects on some women.

Effects and Risks
Intermittent fasting has one major drawback, and that is hunger.

You may also experience a decrease in mental capacity and general weakness.

It may just take some time for your body to adjust to the new meal schedule, so this may be a temporary problem.

Intermittent fasting may be beneficial, but it’s not recommended for people with certain health conditions without first talking to their doctor.

This is especially crucial if:

suffer from diabetes.
Have issues maintaining a healthy blood sugar level.
suffer from hypotension.
Use prescribed remedies.
Are too thin.
Previous experience with an eating disorder.
you’re a woman trying to have a baby.
You have a history of not having periods (amenorrhea).
tend to be pregnant or nursing mothers.
Having said that, the safety profile of intermittent fasting is exceptional. If you are otherwise healthy and well-nourished, going without food for a period of time poses no risk.

To sum up, hunger is the most common negative effect of intermittent fasting. Fasting should not be attempted by those who have certain medical conditions without first talking to their doctor.

Questions Often Asked
The most frequently asked questions about intermittent fasting have been answered below.

Can I have liquids before, during, or after my fast?
Yes. Drinks like water, tea, and coffee that are low in calories are acceptable. Coffee is not improved by sugar. There may be a safe threshold for milk and cream.

Because it reduces hunger, coffee is helpful during a fast.

Isn’t it bad for you to not eat breakfast?
No. Most people who never eat breakfast fit the stereotype of leading unhealthy lives. It’s perfectly healthy as long as you balance it out with a healthy diet the rest of the day.

Can I take vitamins and minerals during my fast?
Yes. It’s important to keep in mind that some supplements, like fat-soluble vitamins, may be more effective when taken at mealtime.

Can I Exercise on a Full Stomach?
Training while fasted is acceptable. Before a fasted workout, some experts suggest taking branched-chain amino acids (BCAAs).

In case you’re looking for BCAA supplements, Amazon has a lot of options.

In what ways, if any, does fasting lead to muscle atrophy?
Muscle loss is inevitable when dieting, so making sure you keep up with your weight training and eat plenty of protein will help you maintain your gains. Intermittent fasting was found to reduce muscle loss compared to sustained caloric restriction in a study published in 2011. (16Trusted Source).

Will I Experience a Metabolism Slump If I Fast?
No. Short-term fasting has been shown to increase metabolism in older studies (14Trusted Source, 15Trusted Source). However, fasts of 3 days or more can cause metabolic suppression (36Trusted Source).

Should Young People Abstain from Food?
It’s probably not a good idea to let your kid fast.

The First Steps
You’ve probably done many intermittent fasts already.

You have probably already fasted for 16 hours or more if you have ever eaten dinner, then slept in and not eaten again until lunch the next day.

It’s how some people’s bodies naturally crave food. They wake up in the morning and just aren’t hungry.

You may want to start with the 16:8 method of intermittent fasting because it is widely regarded as the easiest and most maintainable approach.

If you find the fast to be manageable and you feel good while doing it, you might want to try a more advanced fast, such as a 24-hour fast once or twice a week (Eat-Stop-Eat) or a fast in which you consume only 500 to 600 calories once or twice a week (5:2 diet).

Another option is to fast on your own time, whenever it is most practical, by skipping meals when you aren’t hungry or when you don’t have the time to prepare them.

If you want to reap some of the benefits of intermittent fasting, you don’t even have to do it the “right” way.

Try out a few different methods until you find one you like and can fit into your routine.

The 16:8 method is suggested as a starting point before progressing to longer fasts. Find what works best for you through trial and error.

What Do You Think?
In general, nobody has to try intermittent fasting.

It’s just one of many healthy habits that can make a difference. Real food, exercise, and adequate rest remain the cornerstones of a healthy lifestyle.

You can safely disregard this article and keep doing what works for you if the idea of fasting is repulsive to you.

When it comes to diet, there is ultimately no universally applicable rule. What’s best for you is a diet that you can follow for the long haul.

Some people benefit greatly from intermittent fasting, while others do not. You’ll never know for sure unless you give it a try, but there are four distinct groups to choose from.

Fasting can be an extremely effective method for weight loss and health improvement if you enjoy your experience and find it to be a sustainable way of eating.

Learn more about the topic by reading the article in Spanish.