How Does Intermittent Fasting Work The Science
There is more emerging scientific evidence for how intermittent fasting works.
Mark P. Mattson, Ph.D. is a leading figure in intermittent fasting. Mattsons studies show that fasting can make the body enter ketosis. This means that you burn fat reserves instead of using glucose for your bodys energy. If you want, you can even track this yourself using a ketone monitor.
Intermittent fasting also drops the levels of insulin in your blood. This further aids weight loss.
Why does our body react in this way? Well, your body doesnt know when your next meal is coming, and it needs to get energy from somewhere. This is the whole reason why bodies store fat.
In a state of fasting, the body starts to use glucose, stored in the liver. Eventually, it will use the fat reserves you have built up for energy. Mattson claims that It takes 10 to 12 hours to use the livers energy stores, then what happens is, fats are used for energy.
Intermittent Fasting Has Plenty of Benefits Beyond Fat Burning
Does fasting work exclusively for weight loss and fat burning? It may surprise you that there are a lot of other medical benefits.
The insulin reduction weve already mentioned helps to reduce your chances of getting type 2 diabetes.
On top of this, intermittent fasting is strongly linked to cellular repair within the body. This study shows how intermittent fasting can help to clear out the waste from cells, promoting quick repair and replenishment.
What Can I Eat While Intermittent Fasting
During the times when youre not eating, water and zero-calorie beverages such as black coffee and tea are permitted.
And during your eating periods, eating normally does not mean going crazy. Youre not likely to lose weight or get healthier if you pack your feeding times with high-calorie junk food, super-sized fried items and treats.
But what Williams likes about intermittent fasting is that it allows for a range of different foods to be eaten and enjoyed. We want people to be mindful and take pleasure in eating good, nutritious food, she says. She adds that eating with others and sharing the mealtime experience adds satisfaction and supports good health.
Williams, like most nutrition experts, regards the Mediterranean diet as a good blueprint of what to eat, whether youre trying intermittent fasting or not. You can hardly go wrong when you pick complex, unrefined carbohydrates such as whole grains, leafy greens, healthy fats and lean protein.
When Should I Exercise
When Varady and her colleagues conducted a study that combined alternate day fasting and exercise, they allowed the participants to pick whether they wanted to exercise on a feasting or fasting day, and found there was no strong preference one way or the other. But the researchers were surprised the dieters actually reported feeling more energetic on fasting days.
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How To Do Intermittent Fasting
As briefly explained above, the best approach to fasting is to fast for a minimum of 16 hours including sleep time and to consume food within an 8-hour eating window. Of course, you could be more aggressive and fast for 18 hours, 20 hours, and even up to and over 24 hours in some cases . The tricky thing about fasting for 20 hours is youll only leave yourself a 4-hour eating window, and depending on your goals/objectives and caloric requirements, it can be difficult to consume all the needed calories and nutrients within a 4-hour window.
Personally, whenever I fasted for more than 20 hours, I found it challenging to eat enough food while leaving time for digestion, and in most cases, I ended up consuming my entire caloric intake within a single massive meal, which would take about an hour to eat.
If you are new to intermittent fasting, I suggest starting with a 14-hour fast and 10-hour eating window, then after a few days , scale up to a 16-hour fast then an 18-hour fast. The sweet spot for many is 18-hour fasting.
You can also get a DNA report from 23andme and submit it to Dr. Rhonda Patricks Genome Analysis Tool, and it will make suggestions for your ideal fasting period. My DNA report revealed that genetically I benefit from a 16hr+ daily fast, among lots of other resourceful information.
This Is How Long It’ll Take For Intermittent Fasting To Work
When it comes to getting healthier and toning up your body, one of the most popular of the countless options out there right now is intermittent fasting . IF includes several different approaches to choose from, but most involve eating for only a short period of time during the day and/or limiting the amount of calories you consume. The results are apparent to those who’ve tried the method, but according to the experts, you need at least 10 weeks of following a few basic rules to see any changes.
Read on for more details about how best to make IF work for you, including whether the time of day you’re eating has an impact on your waistline and what other benefits you can expect from the method, aside from a lower number on the scale.
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What Is Intermittent Fasting
Many diets focus on what to eat, but intermittent fasting is all about when you eat.
With intermittent fasting, you only eat during a specific time. Fasting for a certain number of hours each day or eating just one meal a couple days a week, can help your body burn fat. And scientific evidence points to some health benefits, as well.
Johns Hopkins neuroscientist , has studied intermittent fasting for 25 years. He says that our bodies have evolved to be able to go without food for many hours, or even several days or longer. In prehistoric times, before humans learned to farm, they were hunters and gatherers who evolved to survive and thrive for long periods without eating. They had to: It took a lot of time and energy to hunt game and gather nuts and berries.
Even 50 years ago, it was easier to maintain a healthy weight. Johns Hopkins dietitian Christie Williams, M.S., R.D.N., explains: There were no computers, and TV shows turned off at 11 p.m.; people stopped eating because they went to bed. Portions were much smaller. More people worked and played outside and, in general, got more exercise.
Nowadays, TV, the internet and other entertainment are available 24/7. We stay awake for longer hours to catch our favorite shows, play games and chat online. Were sitting and snacking all day and most of the night.
What Are The Benefits Of Intermittent Fasting
Weight loss isnt the only benefit of IF. Fasting is a practice that dates back to ancient times, and in some cultures is still practiced regularly.;
Health benefits are a pleasant side effect of IF, and many of those perks can affect womens health specifically.;
Musculoskeletal health. This includes conditions like osteoporosis, arthritis, and lower back pain. Fasting has been shown to promote hormone secretion from the thyroid. This can promote bone health and help prevent bone fractures.;
Metabolic health. Some women go through menopause in their 50s. Menopause can cause changes in your body that increase belly fat, insulin, and glucose. Fasting can help you decrease your blood pressure, cholesterol, and belly fat, which can improve insulin sensitivity. Fasting can also keep your metabolism on track as you age.;
Mental health. Fasting has been shown to promote mental health. It may reduce anxiety, depression, and the emotional roller coaster that can go hand-in-hand with menopause. Fasting has also been proven to improve self-esteem and reduce stress.;
Other proven benefits of IF include:;
- Improved memory
- Heart health
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Popular Ways To Do Intermittent Fasting
Intermittent fasting has recently become a health trend. Devotees claim it can cause weight loss, improve metabolic health, and maybe even extend life span.
Every method can be effective, but figuring out which one works best depends on the individual.
Several methods of this eating pattern exist. But before embarking on an intermittent fast or deciding how often to fast, you should speak with a healthcare professional.
Here are 6 popular ways to do intermittent fasting.
Can Other Diets Also Be Whole Food Diets
Heres where it gets confusingyes, other diets can also be whole food diets. Eating a whole food diet is a lifestyle choice, but many other diets can exist within a whole foods construct. So, diets like the MIND Diet and Mediterranean Diet are also whole food diets.
For example, here are the foods involved in the MIND Diet:
- Green, leafy vegetables five times a week
- Five or more different colored fruits and vegetables every day.
- Berries five times a week
- Five or more servings of nuts a week
- Olive oil five times a week
- Whole grains five times a week
- Oily fish twice a week or take an algae-based omega-3 supplement
- Legumes and pulses five times a week
- White meat/mix of plant-based proteins twice a week
- No more than one glass of wine a day
- One or two coffee or tea a day max
- Two liters of water a day
Thats pretty much a whole food diet, right? As long as any meat or plant-based proteins are as unprocessed as possible, then it can be a whole food diet.
Other diets, like a vegan diet, for instance, could be whole food diets or not. It really depends if processed foods are included. Some food substitutes are really heavily processed, so its important to read labels really carefully. But its only some, not all.
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What Are The Possible Side Effects
There can be a number of possible side effects of intermittent fasting.40 Heres what to do if you encounter them:
- Hunger is the most common side effect of intermittent fasting. This may be less of an issue if youre already on a keto or low-carb, higher-fat diet.41Learn more
- Constipation is common. Less going in means less going out. However, keep in mind this is a normal response to eating less. It is not a concern and shouldnt require treatment unless you experience significant bloating or abdominal discomfort. Standard laxatives or magnesium supplements can be used, if needed.
- Headaches are common and tend to disappear after the first few times on fasts.42 Taking some extra salt often helps mitigate such headaches.43
- Mineral water may help if your stomach tends to gurgle.
- Other possible side effects include dizziness, heartburn and muscle cramps. Learn more
A more serious side effect is the refeeding syndrome. Fortunately, this is rare and generally only happens with extended fasts when one is undernourished.44
Since most of these side effects are manageable, they do not mean you have to stop your fast. However, if you truly feel unwell, are excessively dizzy, profoundly weak or have other severe symptoms, then you should break your fast.
Just remember to go slowly when you break it and prioritize fluids and salt . And of course, if the symptoms persist, see your doctor immediately.
Common Obstacles To Eating A Healthier Diet
Varady dabbles with intermittent fasting herself, typically for a few weeks after the holidays to lose a few pounds. The 16:8 plan is less intense than the other plans, but if she wants a more rapid weight loss, shell opt for alternate day fasting.
The first five fast days are pretty tricky, but once your body gets adjusted to that kind of up-down pattern of eating, it actually gets really easy, Varady told TODAY.
So how do you boost your chances of intermittent fasting success?
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What Is Intermittent Fasting And Why Would You Do It
Intermittent fasting is not a diet, it’s a pattern of eating. It’s a way of scheduling your meals so that you get the most out of them. Intermittent fasting doesnt change what you eat, it changes when you eat.
Why is it worthwhile to change when youre eating?
Well, most notably, its a great way to get lean without going on a crazy diet or cutting your calories down to nothing. In fact, most of the time you’ll try to keep your calories the same when you start intermittent fasting. Additionally, intermittent fasting is a good way to keep muscle mass on while getting lean.
With all that said, the main reason people try intermittent fasting is to lose fat. We’ll talk about how intermittent fasting leads to fat loss in a moment.
Perhaps most importantly, intermittent fasting is one of the simplest strategies we have for taking bad weight off while keeping good weight on because it requires very little behavior change. This is a very good thing because it means intermittent fasting falls into the category of simple enough that you’ll actually do it, but meaningful enough that it will actually make a difference.
So Is Intermittent Fasting As Good As It Sounds
I was very curious about this, so I asked the opinion of metabolic expert Dr. Deborah Wexler, Director of the Massachusetts General Hospital Diabetes Center and associate professor at Harvard Medical School. Here is what she told me. “There is evidence to suggest that the circadian rhythm fasting approach, where meals are restricted to an eight to 10-hour period of the daytime, is effective,” she confirmed, though generally she recommends that people “use an eating approach that works for them and is sustainable to them.”
So, heres the deal. There is some good scientific evidence suggesting that circadian rhythm fasting, when combined with a healthy diet and lifestyle, can be a particularly effective approach to weight loss, especially for people at risk for diabetes.
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Benefits Of A Whole Food Diet
In a 2014 analysis by Yale University, they concluded that a diet of minimally processed foods close to nature, predominantly plants, is decisively associated with health promotion and disease prevention.
A diet rich in fruit and vegetables or other high-fiber foods like whole grains and nuts is really important in maintaining good long-term health and preventing health problems like diabetes and cancers. These kinds of foods also help our bodies to cope and control the effects of inflammation.
In fact, one review from 2019 stated that diets high in plant foods could potentially prevent several million premature deaths each year if adopted globally. This is a big endorsement for a whole food diet.
Benefits Of Intermittent Fasting
Many of us dont like our eating schedules altered in any way. We get it. Eating what we want when we want is satiating and feels good. However, its not the ideal way to eat to keep our body functioning at optimum levels. So, before we talk about scheduling, its important to know the benefits of incorporating intermittent fasting into your lifestyle. There are many, and research is still being conducted to show further benefits.
Intermittent fasting can help you lose weight.;
Dividing your days and weeks into eating and fasting periods helps you consume fewer calories while being more conscious about what you eat and drink during your consumption time. Those practicing intermittent fasting have fewer calories to burn, which in the end equals weight loss.;
Fasting helps your body stave off disease.;
Periods of fasting allow your body to concentrate on other duties, such as defending itself from pathogens. Ultimately your cells can detect and protect themselves against attacks both from within and outside of the body. Intermittent fasting has even been shown to lessen the possibility of getting certain types of cancer.;
Blood sugar can be regulated by intermittent fasting.;
The foods you consume can immediately be converted into energy while fasting. The caloric boost encourages your body to digest and assimilates the sugars quickly, which helps regulate blood sugar. Intermittent fasting also decreases your bodys dependence on insulin for this breakdown process.
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Shouldyou Try Intermittent Fasting
This type of plan isnt for everyone. There are manyconveniences, though so unlike other tedious diet plans, this one simplifiedyour life more than it adds stress to it.
You will learn how to be more in touch with your hungercues, and how to schedule your eating so that you burn as much fat as possibleduring hours when it seems effortless.
It achieves the same results as some other diet methods, soif you find that fasting isnt for you, you can try a more traditional approachto things, such as scheduled meals and calorie reduction.
Much of what fasting entails is mental. You have tosuddenly learn how to drown out your inner voice that is screaming for foodbecause its time to eat! You wont starve to death going without a meal in 6hours.
You might feel uncomfortable at first, realizing there aretrue hunger pangs that exist when you hadnt felt them in forever. But nothinghorrible is going to happen to you because of fasting.
You already fast when you sleep, and this is just anextension of that. Most Intermittent Fasting participants say you shouldnt goover the 36-hour window of fasting. Thats when you begin to feel sufferinginstead of benefits.
You might experience waves of hunger as you first getstarted with this type of fasting. It will ebb and flow, and during the timeswhen its strongest and you feel like panicking, keep yourself occupied andbusy until it passes.
Cast Aside Doubt And Commit For Sucess With Intermittent Fasting
- While doing intermittent fasting you need to have a glass half full mentality. As a beginner, its easy to be doubtful especially trying out a new diet plan. However, keep in mind that with any diet plan in order to gain fantastic;results you must be;disciplined and proactive.; ;Overall the first couple of days will test your;level of commitment however by taking baby steps your body will adjust.
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