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Intermittent fasting (IF) is one of the most popular health and fitness trends in the world right now.
It is being used to help people lose weight, improve their health, and simplify their lives. Many studies have shown that it has powerful effects on your body and brain, and that it may even help you live longer (1, 2, 3). This is the ultimate beginner’s guide to intermittent fasting..
This is the ultimate beginner’s guide to intermittent fasting.
Intermittent fasting (IF) is a type of eating that alternates between fasting and eating periods. It doesn’t say which foods you should eat, but rather when you should eat them ( $0 In this sense, it’s more accurately described as an eating pattern than a diet in the traditional sense.
The most common intermittent fasting methods are daily 16-hour fasts or 24-hour fasts twice a week.
Fasting has been a part of human evolution for thousands of years. Supermarkets, refrigerators, and year-round food were not available to ancient hunter-gatherers. They couldn’t always find something to eat. As a result, humans have evolved to be able to function for long periods of time without food. In fact, fasting from time to time is more natural than eating three to four (or more) meals per day. Fasting is commonly practiced for religious or spiritual reasons in Islam, Christianity, Judaism, and Buddhism. Intermittent Fasting Methods
The 16/8 method: Also known as the Leangains protocol, it entails skipping breakfast and limiting your daily eating period to 8 hours, such as 1–9 p.m. After that, you fast for 16 hours.
- Eat-Stop-Eat: This entails fasting for 24 hours once or twice a week, such as not eating from dinner one day to dinner the next. The 5:2 diet: This method involves eating only 500–600 calories on two nonconsecutive days of the week, but eating normally on the other five. All of these methods should cause weight loss by reducing your calorie intake, as long as you don’t compensate by eating much more during the eating periods. Many people believe that the 16/8 method is the simplest, most sustainable, and easiest to follow. It’s also the most well-known.
There are several different ways to do intermittent fasting. All of them split the day or week into eating and fasting periods.
Your body, for example, changes hormone levels to make stored body fat more accessible. Your cells also initiate important repair processes and alter gene expression.
Here are some of the physiological changes that occur when you fast:
- Human Growth Hormone (HGH): Growth hormone levels skyrocket, sometimes up to 5-fold. This has a number of advantages, including fat loss and muscle gain (4, 5, 6, 7). Insulin:
- Insulin sensitivity improves and insulin levels drop dramatically. Insulin levels that are lower make stored body fat more accessible (8).
- Cellular repair: When you fast, your cells begin to repair themselves.
- Gene expression: There are changes in the function of genes related to longevity and disease protection (11, 12).
Intermittent fasting’s health benefits are due to changes in hormone levels, cell function, and gene expression.
When you fast, human growth hormone levels go up and insulin levels go down. Your body’s cells also change the expression of genes and initiate important cellular repair processes.
The most common reason for people to try intermittent fasting (13). Intermittent fasting can result in an automatic reduction in calorie intake by forcing you to eat fewer meals. In addition, intermittent fasting alters hormone levels, allowing for weight loss. It increases the release of the fat-burning hormone norepinephrine (noradrenaline) in addition to lowering insulin and increasing growth hormone levels. Short-term fasting may increase your metabolic rate by 3.5% as a result of these hormonal changes. (14, 15) 6–14% Intermittent fasting causes weight loss by changing both sides of the calorie equation by helping you eat fewer and burn more calories. Intermittent fasting has been shown in studies to be a very effective weight loss tool. This eating pattern can cause 3–8% weight loss over 3–24 weeks, which is a significant amount when compared to most weight loss studies (1), according to a 2014 review study. According to the same study, people lost 4–7% of their waist circumference, indicating a significant reduction in harmful belly fat that accumulates around organs and causes disease (1).
In another study, intermittent fasting was found to cause less muscle loss than the more common method of continuous calorie restriction (16). Keep in mind, though, that the main reason for its success is that intermittent fasting allows you to consume fewer calories overall. You may not lose any weight if you binge and eat massive amounts during your eating periods.
Intermittent fasting may slightly boost metabolism while helping you eat fewer calories. It’s a very effective way to lose weight and belly fat.
Intermittent fasting has been studied extensively in both animals and humans.
These studies have shown that it can help you lose weight and improve your physical and mental health. It may even assist you in living a longer life.
The following are the main health benefits of intermittent fasting:
- Weight loss: As previously stated, intermittent fasting can help you lose weight and belly fat without having to restrict calories consciously (1, 13).
- Insulin resistance: Intermittent fasting can lower blood sugar by 3–6% and fasting insulin levels by 20–31%, potentially protecting against type 2 diabetes (1). Inflammation: Some studies show reductions in inflammation markers, which are a key driver of many chronic diseases (17, 18, 19). Intermittent fasting may lower “bad” LDL cholesterol, blood triglycerides, inflammatory markers, blood sugar, and insulin resistance, all of which are risk factors for heart disease (1, 20, 21). Cancer: Animal studies suggest that intermittent fasting may prevent cancer (22, 23, 24, 25).
- Brain health: Intermittent fasting boosts the brain hormone BDNF, which may help new nerve cells grow. It may also help to prevent Alzheimer’s (26, 27, 28, 29).
- Anti-aging: Intermittent fasting has been shown to extend the lifespan of rats. Fasted rats lived 36–83% longer than non-fasted rats (30, 31). Keep in mind that research is still in its early stages.
The majority of the studies were small, short-term, or animal-based. In higher-quality human studies (32) many questions remain unanswered.
Intermittent fasting can have many benefits for your body and brain. It can cause weight loss and may reduce your risk of type 2 diabetes, heart disease and cancer. It may also help you live longer.
One of the biggest roadblocks is the amount of effort required to plan and prepare healthy meals.
Intermittent fasting can make life easier because you don’t have to plan, cook, or clean up as many meals as you used to. As a result, intermittent fasting is extremely popular among the life-hacking crowd, as it improves your health while also simplifying your life. Who Should Be Wary Of Or Avoid It?
One of the major benefits of intermittent fasting is that it makes healthy eating simpler. There are fewer meals you need to prepare, cook and clean up after.
Intermittent fasting is not recommended for everyone.
If you’re underweight or have a history of eating disorders, you shouldn’t fast without first consulting a doctor. It can be downright dangerous in these situations.
Should Women Fast? (
) Intermittent fasting may not be as beneficial for women as it is for men, according to some evidence.
According to one study, it improved insulin sensitivity in men but worsened blood sugar control in women (33). Despite the lack of human studies on the subject, studies in rats have found that intermittent fasting can cause female rats to become emaciated, masculinized, infertile, and miss cycles (34, 35). There have been a few anecdotal reports of women’s menstrual periods stopping when they started doing IF and returning to normal when they resumed their previous eating pattern. Women should be cautious about intermittent fasting for these reasons. They should follow separate guidelines, such as easing into the practice and discontinuing it immediately if they experience any problems, such as amenorrhea (absence of menstruation).
If you’re having fertility problems or trying to conceive, hold off on intermittent fasting for the time being. If you’re pregnant or breastfeeding, this eating pattern is probably not a good idea.
People who are underweight or have a history of eating disorders should not fast. There is also some evidence that intermittent fasting may be harmful to some women.
$0You may also feel tired and your brain may not function as well as it usually does.
This may only be temporary, as your body will need time to adjust to the new meal schedule.
If you have a medical condition, talk to your doctor before attempting intermittent fasting. This is especially important if you have diabetes (
- Are you having trouble controlling your blood sugar? Have a low blood pressure.
- Take your medications.
- You’re overweight. Have a history of eating disorders.
- Are you a woman who is trying to conceive?
- Do you have a history of amenorrhea? Are you pregnant or breastfeeding?
Despite this, intermittent fasting has an excellent safety record. If you’re healthy and well-nourished overall, going without food for a while isn’t dangerous.
The most common side effect of intermittent fasting is hunger. People with certain medical conditions should not fast without consulting with a doctor first.Frequently Asked Questions
$05 Is it permissible to drink liquids during the fast? Yes,
Non-caloric beverages such as water, coffee, and tea are acceptable. Coffee should not be sweetened. It’s possible that small amounts of milk or cream are acceptable.
Coffee can help you stay full during a fast by suppressing your hunger.
$05 Isn’t Skipping Breakfast Unhealthy? No, the issue is that most stereotypical breakfast skippers lead unhealthy lifestyles. The practice is perfectly healthy if you make sure to eat healthy food for the rest of the day.
$05 Is it possible to take supplements while fasting? Yes,
Keep in mind, however, that some supplements, such as fat-soluble vitamins, may work better when taken with food.
$05 Can I Workout While I’m Sleeping? Yes, fasted workouts are acceptable. Before a fasted workout, some people recommend taking branched-chain amino acids (BCAAs). Many BCAA products can be found on Amazon for
$0 Is it True That Fasting Causes Muscle Loss?
Muscle loss can occur with any weight loss method, which is why it’s critical to lift weights and maintain a high protein intake. Intermittent fasting causes less muscle loss than regular calorie restriction, according to one study (16).
$05 Is it True That Fasting Slows Down My Metabolism?
No, studies show that fasting for a short period of time boosts metabolism (14, 15). Longer fasts of three or more days, on the other hand, can slow down metabolism (36).
$05 Is it necessary for children to move quickly? Allowing your child to fast is probably not a good idea.Getting Started
There’s a good chance you’ve done a few intermittent fasts before.
If you’ve ever eaten dinner, then slept late the next day and didn’t eat until lunch, you’ve probably fasted for 16 hours or more. Some people eat in this manner instinctively. In the morning, they simply do not feel hungry.
Many people consider the 16/8 method to be the most simple and long-lasting method of intermittent fasting; you might want to start there.
If you find fasting easy and enjoyable, you could progress to more advanced fasts such as 24-hour fasts 1–2 times per week (Eat-Stop-Eat) or only eating 500–600 calories 1–2 days per week (5:2 diet).
Another option is to simply fast whenever it’s convenient — skip meals when you’re not hungry or don’t have time to prepare them. To reap at least some of the benefits, there is no need to follow a structured intermittent fasting plan.
Experiment with different approaches until you find one that you like and fits into your schedule. Should You Try It?
It’s recommended to start with the 16/8 method, then perhaps later move on to longer fasts. It’s important to experiment and find a method that works for you.
There is no need for anyone to practice intermittent fasting.
It’s just one of many lifestyle changes that can help you live a healthier life. The most important factors to focus on are still eating real food, exercising, and getting enough sleep. If you don’t like the idea of fasting, you can safely disregard this article and continue doing what works best for you.
When it comes to nutrition, there is no such thing as a one-size-fits-all solution. The best diet for you is one that you can maintain over time.
Some people benefit from intermittent fasting, while others do not. The only way to figure out which group you are a part of is to give it a shot. Fasting can be a very powerful tool for losing weight and improving your health if you feel good while fasting and find it to be a sustainable way of eating.
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