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What Fasting Does To Your Body

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Benefits: Mental Strength And Heart Health

What Fasting Does to Your Body: SCIENCE OF RAMADAN

Fasting these first few days can be difficult, but there are mental and physical benefits. Mentally, the act of fasting is an excellent way to exercise your willpower. Similar to the strength runners might feel after pushing their body to run that extra mile, people who choose to fast can feel strength as they fight through those natural urges to eat. Physically, there are incredible cleansing and heart health benefits taking place, too. As BMR lowers, fat in the blood starts to disappear as its metabolized for energy. This process promotes a healthy heart, and for some, improves cholesterol levels by boosting HDL levels.

Muscle Growth And Repair

A study of healthy adults found that 48-hour fasting increased human growth hormone secretion by up to 400%. It also increased the frequency of growth hormone bursts throughout the day.

HGH increases muscle mass and stimulates faster muscle repair. It may also speed up the healing process for wounds and more serious injuries. HGH is so effective that taking it externally is banned in professional sports and is considered doping.

It seems counterintuitive, but occasionally going without food for two days may actually help you build muscle, not lose it.

Why Might Changing Timing Help

But why does simply changing the timing of our meals to allow for fasting make a difference in our body? An in-depth review of the science of IF recently published in New England Journal of Medicine sheds some light. Fasting is evolutionarily embedded within our physiology, triggering several essential cellular functions. Flipping the switch from a fed to fasting state does more than help us burn calories and lose weight. The researchers combed through dozens of animal and human studies to explain how simple fasting improves metabolism, lowering blood sugar lessens inflammation, which improves a range of health issues from arthritic pain to asthma and even helps clear out toxins and damaged cells, which lowers risk for cancer and enhances brain function. The article is deep, but worth a read!

Also Check: What Hours Are Best For Intermittent Fasting

Whats Happening With Your Body: Fat Burning Mode

When you consume a typical diet of carbohydrate rich foods, your body breaks down sugars and starches into glucose. Glucose is the primary source of energy for the body. However, when you fast or go into ketosis glucose becomes limited, and your body must turn to fat stores for the energy it requires. Your body breaks fat down into glycerol and fatty acids. The liver synthesizes ketones using glycerol. The glycerol is broken down by the liver for additional glucose, and finally, those ketones are used by your brain as glucose becomes less available.

Does Fasting Detoxify The Body

What Intermittent Fasting Does To Your Body

Here’s where the debate gets intense.

“There is no scientific evidence it will detox the body. The issue of fasting to cleanse the body has no biological basis because the body is real good at that by itself,” says Fernstrom. “The liver is a natural detox center the lungs, the colon, the kidneys, and the skin get rid of toxins.”

But Fuhrman, who has supervised hundreds of patients’ fasts for medicinal purposes, disagrees.

“We know that the body is unable to rid itself of toxins when we eat a diet low in nutrients,” and that applies to most Americans, even those who think they are healthy, he says.

“Americans eat 51% of their diet from processed foods and foods low in phytochemicals and antioxidants,” he says. “So you see a buildup of waste products in the cells — AGE, advanced glycation end products — that build up in cellular tissues and lead to atherosclerosis, aging, diabetes, nerve damage, and the deterioration of organs. This is basic science and physiology every doctor learns in medical school.”

Along with improving your overall diet, fasting is one solution to that buildup of AGE, according to advocates like Fuhrman.

“Fasting allows the body to most effectively remove these waste products,” he says. “The body is designed to fast we do it every night.”

“And the fat is where the body stores many of the toxins it absorbs from the environment,” Fuhrman says.


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This Is Your Body On Intermittent Fasting

Its no surprise that intermittent fasting is one of the most popular types of eating plans. You dont need to measure out food or buy any prepackaged shakes. There are no required weigh-ins or calorie counting. All you really have to do is not eat during certain hours. Its pretty simple.

There are different ways to go about it, of course. Most people do the 16:8 diet, in which you fast for 16 hours and then eat within an eight-hour window. Theres also the 5:2 diet, where you drastically cut back on calories just two days a week, and there are 24-hour fasts, where you dont eat anything one day each month.

Regardless of the method, significantly restricting when you eat can throw your body for a loop and cause a handful of odd side effects. Intermittent fasting may not be suitable for everyone.

Its important to know what to expect before you jump into any new eating habit. Heres what happens to you mentally, physically and emotionally when youre fasting intermittently.

Fasting And The Keto Diet

You can also combine fasting with a ketogenic diet.

Several of the benefits of intermittent fasting come from your body being in ketosis a state in which you burn fat as your main energy source.

By eating a ketogenic diet, you can get your body into ketosis before you start fasting. A keto diet suppresses hunger and improves your health on its own. Pairing it with fasting provides even more health benefits.

You can start a keto diet today with a quick trip to the grocery store.

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How To Get The Most Out Of Your Intermittent Fasting

To get the most out of your intermittent fasting lifestyle, follow these tips:

  • Keep yourself hydrated by drinking lots of water.
  • Drink cinnamon tea to suppress hunger you can have it during fasting hours.
  • Since exercise triggers hunger, do it just before or during your feeding window.
  • Avoid junk food during feeding hours and stick to wholesome foods.
  • Consume healthy teas during your fasting hours, as low-calorie drinks are allowed during fasting hours.

The Origins Of Fasting

What Fasting Does To Your Body

Despite being popularised by todays diet world, the practice of fasting actually dates back centuries and is thought to be one of the oldest therapies in medicine. In the 5th century BC, Hippocrates, the father of Western medicine, recommended abstaining from food to aid the healing process. In Ayurvedic medicine, fasting once a week is thought to promote digestive clearance.

Fasting plays a central role in cultural and religious practices, with all major religions utilising a fast in one form or another. Christian Lent and Muslim Ramadan are two well-known examples. Whether it involves the abstinence of food and drink or a lighter, lower calorie form of eating, many argue that going without food for periods of time is something we have evolved to do.

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Won’t You Just Eat More Later

You might. Still, you should try to eat a healthy amount of food and not stuff yourself after a fast. Quality still counts. But even among people who eat the same number of calories, those who fast tend to have lower blood pressure, higher insulin sensitivity, more appetite control, and easier weight loss.

How To Get Started

When first trying IF, the transition can be challenging, Mattson admits.

Many fasters report uncomfortable, even painful hunger pangs as they abstain from food. Mattson suggests people take it slow, trying different kinds of IF to see what works with their goals and routine. He advises first narrowing the âfeeding windowâ from an initial unrestricted period down to 12 hours, then 10 hours, then eight hours, before finding a feeding window that is sustainable.

During the first week or two of IF, fasters may notice their stomachs grumbling or feel a sense of hollowness. Some people are exhausted, lightheaded, or shaky from diminished blood sugar on fasting days. Others experience poor concentration, irritability, mood swings, and even dizziness. In particular, people who work in long shifts or with heavy machinery should take more care when fasting to stay hydrated, rested, and alert.

After about a month, people typically feel better and less hungry, says Mattson.

Tello agrees: âThe longer you can go between meals, the less hungry you are. I think a lot of peopleâs hunger levels actually decrease as opposed to the very low calorie diet where youâre constantly feeding yourself small, tiny bits of food. Thatâs like a tease all day long.â

Mattson encourages fasters to be patient and wait for those side effects to pass.

Read Also: How To Do Fasting To Lose Weight

May Aid In Preventing Cancer

It should be no surprise now that fasting can help rid the body of toxins, but cancer?

Now, fasting may not completely prevent you from getting cancer, but it can help in the spreading of it and tumor growth.

For people going through chemotherapy, intermittent fasting can help suppress many of the side effects. The only thing thats worrisome is the small amount of lightheadedness and hunger you will be feeling. Many people seem to not have an appetite with some chemotherapy so the hunger really may not be much of a problem at all.

Since fasting gets rid of a ton of toxins that can sneak their way into your body, it makes sense that it may help prevent certain types of cancer. Cancer attacks your cells, but when there are no toxins in your body that can attack any of your cells, then cancer cant form.

Healing Activity On Day :

What Intermittent Fasting Does To Your Body

Here are some of the really cool things that ramp up on Day 2 of the fast. You get these on Day 1 but in smaller amounts and each successive day up until Day 5, the levels continue to increase.

  • Resets the Microbiome: Fasting helps to de-weed the gut flora and pulls out a lot of good and bad microbes . This is a really good thing as the food abundance we have in our society favors the development of a lot of bad gut microbes.
  • Cellular Autophagy: The body gets to work on intracellular cleansing, breaking down older, weaker cells and cellular components such as mitochondria and using the raw materials to rebuild new cells .
  • Rise in Human Growth Hormone: Human growth hormone goes up significantly in order to help preserve our muscle mass. This also helps to improve immune function, bone tissue and fat burning.
  • Stem Cell Rise: The body creates new white blood cells, repairs the intestinal membrane and increases new and youthful stem cells in joints and tissues that have suffered through damage and need repair .
  • Resets the DNA: We all have certain bad genes turned on that amplify inflammation and lead us down a road to chronic degeneration. Some of these genes promote things like obesity, allergies, autoimmune conditions, etc. Fasting turns these genes off like flicking a light switch off so they go dormant . Depending upon how many of these genes you have turned on, you may need repeated fasts or yearly/biyearly fasts to turn them all off or keep them off.
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    The Five Stages Of Intermittent Fasting

    . In this state, your body starts to break down and burn fat.

    Some of this fat is used by the liver to produce ketone bodies . The two main ketones, acetoacetate and -hydroxybutyrate , serve as an alternative energy source for the cells of your heart, skeletal muscle, and brain, when glucose isnt readily available. Did you know that your brain uses up some 60% of your glucose when your body is in the resting state? During intermittent fasting, ketone bodies generated by your liver partly replace glucose as fuel for your brain as well as other organs. This ketone usage by your brain is one of the reasons that intermittent fasting is often claimed to promote mental clarity and positive mood ketones produce less inflammatory products as they are being metabolized than does glucose, and they can even kick-start production of the brain growth factor BDNF! Ketones have also been shown to reduce cellular damage and cell death in neurons and can also reduce inflammation in other cell types.

    As their level in your bloodstream rises, ketones can act as signaling molecules, similar to hormones, to tell your body to ramp up stress-busting pathways that reduce inflammation and repair damaged DNA for example.

    Within 24 hours, your cells are increasingly recycling old components and breaking down misfolded proteins linked to Alzheimers and other diseases . This is a process called autophagy.

    It Protects Your Ticker

    While were talking about risk factors for heart disease, high cholesterol is another biggie. In a small 2010 study, fasting every other day slashed participants levels of LDL cholesterol and triglycerides by 25 and 32 percent, respectively.

    In fact, long-term findings suggest that routine fasters are more than 70 percent less likely to have heart failure than folks who never fast.

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    The Pice De Rsistance: It May Help You Live Longer

    Fasting seems to help cells repair themselves, which might be why its tied to a lower risk of many diseases. Fasting could reduce the risk of several metabolic and cardiovascular conditions and having better overall health and less likelihood of illness could contribute to a longer life.

    So, will limiting your food intake help you see 100? No guarantees, of course, but back in 1982, a study looking at rats found that rodents who fasted every other day aged at a slower rate and lived a whopping 83 percent longer than rats who didnt fast.

    How Your Body Responds To Fasting

    What Happens To Your Body When Fasting for 24 Hours

    Thebody runs on energy the same way a car runs on fuel. The most important sourceof energy is glucose, its present in carbs.

    Whencarbs are digested, the glucose is stored in your liver and muscles, waiting tobe let into your bloodstream when you need it.

    Intermittent Fasting messes up this process because no carbs are being let into your body. This results in the liver using up all the glucose in it and getting your body in fasting mode.

    Yourbody then begins burning more calories, using the fat as its new source ofglucose. Thats the state your body is in after 24 hours of fasting, which isthe safe zone.

    When your body runs out of fats to burn intoenergy, it gets into survival mode and starts to burn muscle tissue for energy.That only occurs after days and weeks with no food, which is not an option inthe one-day fasting were talking about.

    Read Also: What To Have During Intermittent Fasting

    Health Information You Can Trust

    We pride ourselves on being your source for the best, scientifically-accurate advice for healthy living.

    This article contains references to scientific journals and peer-reviewed research. The numbers in brackets correspond with the list of references at the end of the article.

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    While fasting is nothing new, it is experiencing a resurgence in popularity as many discover its potential health benefits. If you are planning your first fast or looking for ways to improve your next one, there are a few things you should do to prepare. The first step is learning about the different stages of fasting. This knowledge helps you mentally and physically prepare for what happens to your body when you fast.

    The stages of fasting outlined below are based off a water fast, a traditional fast in which you abstain from any food and only drink water for 12-48 hours or longer. Personal experiences can vary depending on the type of fast, age, or health of the individual, but these should give you a general idea of what to expect when you fast.

    The Stages of Fasting- In-depth Interview with Dr. Goldhamer & Dr. Group

    Length: 93 minutes

    You Might Lose Weight

    Many health experts, including personal trainer Jillian Michaels, say that intermittent fasting actually isnt that great for weight loss. Thats because youre not necessarily eating less or cutting back on calories. There are just longer gaps in your day when youre not eating at all.

    That said, many people do lose weight because they consume fewer calories during those restricted food hours.

    Eating for only eight hours a day also makes it less likely that youre having a big meal right before bedtime. Our metabolism goes down when we sleep and we burn fewer calories. Nighttime eating has been linked to both obesity and diabetes.

    Intermittent fasting really does keep you from doing some really bad things, which is to eat a big meal before you go to bed, said Dr. John Morton, a bariatric surgeon with Yale Medicine. Big meals before bed are probably the worst thing you can do when it comes to weight loss, he added.

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    Stage 5 Fasting : Stem Cells And Immune Function

    The final stage of fasting begins after a full three days without food.

    Before you read about the benefits, note that a 72-hour fast is a serious undertaking. If youre going to try it, make sure you drink plenty of water, get plenty of electrolytes like sodium, magnesium, and potassium, and stop fasting if you feel lightheaded or otherwise unwell.

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