How Does Intermittent Fasting Work
There are several different ways to do intermittent fasting, but they are all based on choosing regular time periods to eat and fast. For instance, you might try eating only during an eight-hour period each day and fast for the remainder. Or you might choose to eat only one meal a day two days a week. There are many different intermittent fasting schedules.
Mattson says that after hours without food, the body exhausts its sugar stores and starts burning fat. He refers to this as metabolic switching.
Intermittent fasting contrasts with the normal eating pattern for most Americans, who eat throughout their waking hours, Mattson says. If someone is eating three meals a day, plus snacks, and theyre not exercising, then every time they eat, theyre running on those calories and not burning their fat stores.
Intermittent fasting works by prolonging the period when your body has burned through the calories consumed during your last meal and begins burning fat.
Improved Workouts Thanks To Intermittent Fasting
According to PubMed, training with limited carbohydrate availability can stimulate adaptations in muscle cells to facilitate energy production via fat oxidation.
Which means, when you workout during the fasting window of your 12 hour intermittent fasting, your body gets better at burning fat for energy since there are no foods to pull from.
Can Help You Lose Weight And Visceral Fat
Many of those who try intermittent fasting are doing it to lose weight .
Generally speaking, intermittent fasting will make you eat fewer meals.
Unless you compensate by eating much more during the other meals, youll end up taking in fewer calories.
Additionally, intermittent fasting enhances hormone function to facilitate weight loss.
Lower insulin levels, higher HGH levels, and increased amounts of norepinephrine all increase the breakdown of body fat and facilitate its use for energy.
For this reason, short-term fasting actually increases your metabolic rate, helping you burn even more calories .
In other words, intermittent fasting works on both sides of the calorie equation. It boosts your metabolic rate and reduces the amount of food you eat .
According to a 2014 review of the scientific literature, intermittent fasting can cause weight loss of 38% over 324 weeks. This is a huge amount .
The study participants also lost 47% of their waist circumference over 624 weeks, which indicates that they lost lots of visceral fat. Visceral fat is the harmful fat in the abdominal cavity that causes disease .
One 2011 review also showed that intermittent fasting caused less muscle loss than continuous calorie restriction .
However, a 2020 randomized trial looked at people who followed the 16/8 method. In this diet, you fast for 16 hours a day and have an 8-hour window to eat.
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How Much Weight Can You Lose On 1: 8 Diet
To lose weight on the 16:8 diet, its important to match the fasting with healthy eating and exercise. If done so correctly, theres a typical weight loss of around seven to 11 pounds over a ten week period. This is according to a review of 40 different studies published in Molecular and Cellular Endocrincology who found that on average, someone weighing just over 90kg would lose 5% of their total body weight in the ten week period.
A 2018 study published in the Journal of Nutrition and Healthy Eating revealed that the 16:8 diet plan can help people lose weight, without having to count calories as the 8-hour fast produces the same kind of calorific restriction and weight loss.
However, whether theres a distinct weight loss advantage achieved on the 16:8 diet compared to other diets remains to be seen. Some studies have demonstrated that theres almost no difference between people who do intermittent fasting compared those who count calories and cut back on unhealthy food.
What Do Studies Show
Although you have probably heard that breakfast is the most important meal of the day, this isnât actually true.
Take a look at the facts more than 90 percent of Americans eat breakfast and more than 50 percent of Americans are overweight. If eating breakfast helped you to lose weight, then why all the overweight people? Studies back up the truth that breakfast has nothing to do with losing weight.
Another myth is that you need to eat 5 or 6 small meals a day to âstoke the fire of your metabolism.â Again, there are plenty of studies showing that this isnât true either.
Is Intermittent Fasting Right For You
Intermittent fasting isnt for everyone. However, if you do decide to try it, Dr. Viana notes that consistency is key. Intermittent fasting is a powerful tool to help change lifestyle, but before doing it, one should consider if they will be able to maintain it in the long run, he says.
His overall view on eating is that it needs to be something natural and uncomplicatednoting that intermittent fasting can be too restrictive for many people. I like the philosophy of mindful eating very much, which is essentially to get rid of the diet mentality. In my opinion, we tend to overcomplicate eating and that leads to failure.
Also, keep in mind that what you eat should be your first priority over when you eat. What is most important is to eat a healthy diet that contains little or no processed food and is rich in lean protein, whole grains and vegetables , says Dr. Viana.
If you do decide to incorporate intermittent fasting into your dietary plan, consult with your physician firstespecially if you have any preexisting health conditions or are on certain medications.
Our 16 8 Fasting Method Conclusion:
The 16 8 Fasting method is best suited for men that eat healthy and want to establish the health benefits from fasting 16 hours and eating their daily caloric intake in 8 hours a day.
Yes, the way I am describing this, it seems simple in theory. However, I have tried this method before and as a woman, it did negatively adjust my hormones and reduced my metabolism. Carefully consider 16 8 Fasting and work with your doctor before embracing this method.
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Intermittent Fasting: What Breaks A Fast On Keto
A keto diet is a kind of fasting that aims at achieving some of the weight loss goals as the intermittent fasting. The keto diet involves the consumption of low-calorie food and drinks. While you depend mostly on calories from fat, others are sourced from a moderate intake of protein and partial or total abstinence from carbs . By implication, when you are on this diet, you are expected to abstain from high-calorie food and drinks such as high carb proteins, alcoholic beverages, soft drinks, and soda. While keto diet aims at reducing the total intake of calories in meals, intermittent fasting focuses more on structuring how much you can eat at a time.
How Sensible Intermittent Fasting Can Keep You Healthy
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Studies suggest that intermittent fasting typically, eating only during an eight-hour period or eating only every other day could have many potential benefits, including improvements in glucose and cholesterol levels, blood pressure and weight.
The benefits are thought to result from a process called metabolic switching, which is when the body goes into a fasting state and begins using body fat instead of glucose to meet its energy needs. Intermittent fasting helps preserve the bodys normal interplay between the hormone insulin and blood glucose, preventing insulin resistance . Metabolic switching also signals the body to activate maintenance and repair systems, which aid in disease prevention.
But intermittent fasting isnt for everyone. Going for long periods without food may be too extreme for some older adults, people with diabetes, and those who must take certain medications at designated hours, among others, says Dorothy Sears, a professor of nutrition at Arizona State University College of Health Solutions in Phoenix.
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Diet Plan: What Can You Eat And What Are The Benefits
The 16:8 diet has been one of the most popular diet plans weve seen in years and with good reason.
The 16:8 plan also called the 8-hour diet is an easier and more consistent way of fasting that avoids heavily calorie restricted days found in other popular intermittent fasting plans like the 5:2 diet or Fast 800 calorie diet.
A famous fan of the 16:8 intermittent fasting plan is Hollywood icon Jennifer Aniston. In an interview with the Radio Times, Jennifer revealed that shes a big fan of intermittent fasting in general but specifically this plan. I do intermittent fasting, so no food in the morning. She said, I noticed a big difference in going without solid food for 16 hours.
Health Benefits Of Fasting Backed By Science
Despite its recent surge in popularity, fasting is a practice that dates back centuries and plays a central role in many cultures and religions.
Defined as the abstinence from all or some foods or drinks for a set period of time, there are many different ways of fasting.
In general, most types of fasts are performed over 2472 hours.
Intermittent fasting, on the other hand, involves cycling between periods of eating and fasting, ranging from a few hours to a few days at a time.
Fasting has been shown to have many health benefits, from increased weight loss to better brain function.
Here are 8 health benefits of fasting backed by science.
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Slim Down Your Supper
Most Americans consume almost 45 percent of their total daily calories at dinner and in an after-dinner snack. A healthier goal, Sears says, is 30 percent. Thats 600 calories for someone who usually eats 2,000 calories a day.
One way to downsize the dinners that you prepare is to make them the healthiest meal of the day. Try eating lots of vegetables, which are naturally low in calories, says Courtney M. Peterson, an assistant professor in the Department of Nutrition Sciences at the University of Alabama at Birmingham. That means you can eat a large portion so that youre not hungry afterward and still consume fewer than 600 calories. The fiber from those foods will also help you feel fuller.
And if you dont overdo it on calories in the evening, Peterson says, you can afford to have a bigger breakfast and lunch, when your body is primed for food processing.
Recommended Foods And Tips
While the 16:8 intermittent fasting plan does not specify which foods to eat and avoid, it is beneficial to focus on healthful eating and to limit or avoid junk foods. The consumption of too much unhealthful food may cause weight gain and contribute to disease.
A balanced diet focuses primarily on:
- fruits and vegetables, which can be fresh, frozen, or canned
- whole grains, including quinoa, brown rice, oats, and barley
- lean protein sources, such as poultry, fish, beans, lentils, tofu, nuts, seeds, low fat cottage cheese, and eggs
- healthful fats from fatty fish, olives, olive oil, coconuts, avocados, nuts, and seeds
Fruits, vegetables, and whole grains are high in fiber, so they can help keep a person feeling full and satisfied. Healthful fats and proteins can also contribute to satiety.
Beverages can play a role in satiety for those following the 16:8 intermittent fasting diet. Drinking water regularly throughout the day can help reduce calorie intake because people often mistake thirst for hunger.
The 16:8 diet plan permits the consumption of calorie-free drinks such as water and unsweetened tea and coffee during the 16-hour fasting window. It is important to consume fluids regularly to avoid dehydration.
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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.
Cons Of Intermittent Fasting For Women
“Despite the benefits found in research, it’s important to consider the context and remember that it’s not appropriate for all people at all times,” says Greaves. “Women of reproductive age need to be particularly careful with intermittent fasting as their bodies are more sensitive to stressors like prolonged fasting and caloric restriction.”
Greaves explains, “Intermittent fasting itself is a stressor on the body, and in the context of our modern day life that’s already filled with chronic emotional, physiological and environmental stressors, IF might do more harm than good. Fasting increases cortisol which can lead to blood sugar dysregulation, increased insulin resistance, lean muscle loss, fatigue and disruptions to thyroid function over time. In the short-term fasting may lower thyroid stimulating hormone, but elevated cortisol on a persistent basis can reduce the conversion of thyroid hormone.”
“Fasting can also lead to undereating, which we know negatively influences female hormones in a variety of ways,” Greaves says. The caloric restriction caused by intermittent fasting could lead to loss of menstrual cycle and interfere with fertility .
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Hour Intermittent Fasting Schedule
The 12 hour intermittent fasting schedule feels the easiest, least painful and most natural method of fasting. If your last meal ends at 8pm, your next meal does not begin until 8am. If you eat a late evening snack at 10pm, then you dont eat your next meal until 10am.
This method of 12 hour intermittent fasting is flexible, much better for womens hormones and metabolism balances. Plus, you get all of the health benefits of intermittent fasting.
The Benefits Of Intermittent Fasting
I was skeptical, but it turns out there is something to be said for a daily fast, preferably one lasting at least 16 hours.
Ive long thought the human body was not meant to run on empty, that fasting was done primarily for religious reasons or political protest. Otherwise we needed a reliably renewed source of fuel to function optimally, mentally and emotionally as well as physically.
Personal experience reinforced that concept Im not pleasant to be around when Im hungry. Theres even an official name for that state of mind, confirmed by research: Hangry!
But prompted by recent enthusiasm for fasting among people concerned about their health, weight or longevity, I looked into the evidence for possible benefits and risks of what researchers call intermittent fasting. Popular regimens range from ingesting few if any calories all day every other day or several times a week to fasting for 16 hours or more every day.
A man I know in his early 50s said he had lost 12 pounds in about two months on what he calls the 7-11 diet: He eats nothing from 7 p.m. until 11 a.m. the next morning, every day.
It takes 10 to 12 hours to use up the calories in the liver before a metabolic shift occurs to using stored fat, Dr. Mattson told me. After meals, glucose is used for energy and fat is stored in fat tissue, but during fasts, once glucose is depleted, fat is broken down and used for energy.
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Do Calories Matter When Fasting Summary
- Fasting studies have shown that reducing the hours we consume food causes weight loss without conscious food intake restrictions.
- Consistent adherence to a fasting routine may reduce the need to count calories.
- You can lose your ability to recognize true hunger due to a poor diet, resulting in an increased need to track your calorie intake.
- Pairing intermittent fasting with a low carb/high-fat diet will give you a weight-loss edge and could reduce your need to track calories.
Best Intermittent Fasting Schedules To Reduce Insulin Resistance
Popular intermittent fasting protocols range from fasting a few hours each day, fasting every other day, or doing a modified fast a few days of the week. So, theres not a single, best way to fast to improve your insulin sensitivity. Studies conducted on humans show the best type of IF schedule is the one that works for you.
One 2018 study showed a 18:6 fasting protocol , improved insulin sensitivity in men with prediabetes. Another smaller study of patients with diabetes showed that various schedules of 24-hour fasts were beneficial to reducing insulin resistance. This review of 12 studies of patients following some form of IF showed insulin sensitivity improved, regardless of the type of fasting protocol they followed.
IF is flexible. According to Jason Fung MD, founder of The Fasting Method, the most crucial factor of an IF diet is the fasted state will lower your insulin levels. The style of intermittent fasting that fits your lifestyle and is easiest to maintain will be your most effective way to fast for better insulin sensitivity.