Cons Of Intermittent Fasting
Intermittent fasting is one way to regulate your calorie intake and work toward improving your metabolic health.
Though the eating pattern can certainly be part of a healthy diet, it will likely take some adjusting to in the beginning. Plus, simply put, intermittent fasting is not right for everyone.
Here are a few downsides you could encounter when first trying intermittent fasting.
What Is Intermittent Fasting
Intermittent fasting is the practice of fasting for a set amount of hours each day, followed by a window of time in which you are permitted to eat.
During the fasting period, you need to avoid solid foods and limit your diet to calorie-free beverages like water, coffee, and unsweetened teas. During the eating window, you can consume solid foods but are encouraged to follow a balanced diet and avoid junk foods.
While not a weight loss strategy, intermittent fasting may result in weight loss if you consume fewer calories than you are using for energy.
Some people find it helpful to follow the Mediterranean diet while doing intermittent fasting to ensure that they are getting enough nutrients during their eating window. The Mediterranean diet emphasizes whole grains, fruits, vegetables, lean proteins, seafood, and healthy fats.
Counting Calories Beats Fasting Diets For Weight Loss
WEDNESDAY, June 16, 2021 — Intermittent fasting diets are all the rage, but new clinical trial results indicate they don’t work any better than simple calorie cutting.
People who simply cut their daily calories by 25% lost the most weight and fat tissue in three weeks of dieting, compared with two groups following different intermittent fasting regimens, an international team of researchers reported.
There also was no difference between the groups when it came to heart health, metabolism or gene expression related to fat cells, researchers found — in other words, no hidden benefits to fasting.
“Standard dieting may be more effective than intermittent fasting for reducing body fat,” said senior researcher James Betts, a professor of metabolic physiology with the University of Bath’s Center for Nutrition, Exercise and Metabolism in England.
Fasting diets require that people refrain from eating, either on specific days of the week or during certain windows of time during the day.
This clinical trial tested the merits of an alternate-day intermittent fasting schedule, in which people would fast for one day and then on the next consume as much as twice their usual daily calories.
The study was published June 16 in the journal Science Translational Medicine.
The fasters also didn’t have any benefits when it came to their levels of cholesterol, blood sugar or insulin, results showed.
Two U.S. nutrition experts not involved with the study agreed with the findings.
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Eat One Of These 4 Diets To Extend Your Life: New Harvard Study
However, not all experts are in agreement.
Tim Spector, professor at Kings College London, described calorie counting as complete nonsense in an interview on The Diary of a CEO With Steven Bartlett podcast last week.
There has never been any long-term study showing that calorie counting is an effective way to lose weight and maintain weight loss after the first few weeks, the dietitian declared.
Meanwhile, the Johns Hopkins researchers conceded that their six-month-long study still left them with questions about the potential benefits of timerestricted eating patterns, especially the challenges with maintaining this eating behavior.
So What Should You Focus On Instead
The secret to long-term weight loss is to maintain your basal metabolism. What doesnt put you into starvation mode? Actual starvation! Or at least the controlled version, intermittent fasting.
Fasting triggers numerous hormonal adaptations that do NOT happen with simple caloric reduction. Insulin drops precipitously, helping prevent insulin resistance. Noradrenalin rises, keeping metabolism high. Growth hormone rises, maintaining lean mass.
Over four days of continuous fasting, basal metabolism does not drop. Instead, it increased by 12%. Neither did exercise capacity, as measured by the VO2, decrease, but is instead maintained. In another study, twenty-two days of alternate daily fasting also does not result in any decrease in RMR.
Why does this happen? Imagine we are cavemen. Its winter and food is scarce. If our bodies go into starvation mode, then we would become lethargic, with no energy to go out and find food. Each day the situation gets worse and eventually we die. Nice. The human species would have become extinct long ago if our bodies slow down each time we didnt eat for a few hours.
No, instead, during fasting, the body opens up its ample supply of stored food body fat! Yeah! Basal metabolism stays high, and instead we change fuel sources from food, to stored food . Now we have enough energy to go out and hunt some woolly mammoth.
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What Is The 1: 8 Diet
The 16:8 diet is a form of intermittent fasting where you break the day into two parts: a 16-hour fasting period and an 8-hour period where you consume all your calories.
The 16:8 stems from the 8-Hour Diet book by author David Zinczenko and Peter Moore , former editor-in-chief of Men’s Health. The two created the plan off the back of the popular 5:2 diet, with the main difference being the longer fasting time between eating sessions. This, they say, gives the body the time it needs to process food and burn away extra fat.
The 8-Hour Diet by David Zinczenko and Peter Moore –
Suzie Sawyer , founder of Nutrition Lifestyle, says, “There are no restrictions on the types or amounts of food that a person can eat during the 8-hour window. This flexibility makes the plan relatively easy to follow.”
Talk To Your Primary Care Doctor
He or she can determine if this eating style would be beneficial for your body. If you have questions about what is right for you, it’s important to talk to healthcare professionals, Lowden says. Everybody is an individual, and your specific doctor might have preferences about what you do and don’t do based on your specific circumstances.
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Intermittent Fasting May Not Be As Helpful For Losing Weight As Once Thought Study Finds
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Are snacks before bed your vice? Or do you prefer to wait a few hours after you wake up to eat?
The timing of meals may not have as big an impact on weight as once thought, according to a new study.
The study tracked the portion sizes and eating times of 547 people, in addition to data on their health and weight, over the course of six years. The data showed no association between an interval of the day in which people had their meals and their weight, according to the study published Wednesday in the Journal of the American Heart Association.
Restricting eating times, as seen in diet trends such as intermittent fasting, has been a popular method to try to lose weight in recent years.
But the researchers found no association between restricting eating times and weight loss, said principal investigator of the study Dr. Wendy Bennett, an associate professor of medicine in the division of general internal medicine at Johns Hopkins School of Medicine. That included how long people ate after waking up, how long their window of eating was throughout the day and how close to going to bed they ate, she noted.
Instead, smaller meals were associated with weight loss, she said.
You Can Either Lose Weight With Fasting Or By Counting Calories
Some people swear by intermittent fasting to get that belly gone, while others say that counting calories is the only way to keep up consistent and successful weight loss in the long term. Well, as some scientists intrigued by the question of what works best recently found in a study published in JAMA Internal Medicine, it may not really matter much.
The randomized clinical trial went from 2011 to 2015, and tracked 100 obese subjects in one of three groups for one year. Group one was on an alternate-day fast, which featured 25% of calories needed on fast day, and then 125% of daily caloric needs on the other days. Another bunch of patients were given a regular daily calorie restriction diet of 75% of the calories needed each day, and the third group remained a control.
Once the year was up, researchers found that the weight loss between the fasting and calorie-restriction groups was not significant6% vs. 5.3%. The study concluded: The results of this randomized clinical trial demonstrated that alternate-day fasting did not produce superior adherence, weight loss, weight maintenance, or improvements in risk indicators for cardiovascular disease compared with daily calorie restriction.
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Fasting Reduces Calorie Intake
Many of the intermittent fasting studies that have been performed showed that by merely reducing the number of hours during which participants consumed food, they lost weight. In many cases, there were no restrictions placed on the participants regarding what or how much food they could eat during their eating window .
In my book, Intermittent Fasting Diet Guide & Cookbook, I reviewed many of these studies. The obvious question that these studies lead us to ask is, Does that mean calories are unimportant when you are fasting?
In other words, can you eat whatever you want without consequences, as long as you eat everything within fewer hours? After all, it worked for the research participants. Lets take a look at what it means to be in a study.
Is It Good Or Bad To Exercise While Intermittent Fasting
According to Harvard Health, one theory on the pro-exercise side is that exercising in a fasted state may make you burn fat. Lowden explains that the body needs sugar or some sort of energy to perform well while exercising. Normally, the energy comes from sugar molecules, which are stored as glycogen in the liver. If you start exercising, youre more likely to deplete those stores, and then your body has no choice but to go into a more anaerobic breakdown to give you the energy you need, she says. Instead of burning through sugars that aren’t available, your body is forced to burn through another energy source: fat.
But you may not have enough energy to exercise as intensely as you normally would. Peak performance or even feeling good while exercising is much easier if you eat, Lowden says.
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Intermittent Fasting No Better For Weight Loss Than Just Counting Calories
In one of the longest trials of its type ever conducted researchers have found limiting food intake to a short period of time every day is no more effective a dietary strategy than simple calorie counting. The year-long experiment ultimately found calorie restriction to be the most important part of any weight loss plan.
Over the last decade fasting diets have increased in popularity, with advocates claiming they are the most effective way to lose weight and improve metabolic health. This dietary strategy can take a variety of forms, from alternate-day fasting to time-restricted feeding .
This new research focused specifically on a type of time-restricted feeding informally known as the 16:8 diet, which involves limiting all food intake to an eight-hour period every day. In this case the trial limited its fasting cohort to eating only between 8 am and 4 pm.
The trial recruited 139 subjects, all either overweight or obese but otherwise healthy. The cohort was randomly split into two groups: one group tasked with a time-restricted feeding strategy and another that could eat at any time. Both groups were required to limit their caloric intake each day: men no more than 1,800 calories and women no more than 1,500 calories. The trial lasted 12 months.
People With Other Chronic Diseases
Not much is known about how fasting will affect many chronic diseases, including diabetes, but negative side effects such as dizziness and nausea may be more pronounced for these people, according to the 2019 Nutrients study. You have to be careful when you have medical issues that could be worsened by not eating regularly, Lowden says. If you take medication for blood pressure or heart disease, you may be more prone to electrolyte imbalances that come with fasting, so fasting may not be recommended, per Harvard Health.
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What Are The Different Forms Of Calorie Restriction And Fasting
Calorie restriction is a consistent pattern of reducing average daily caloric intake, while fasting regimens primarily focus on the frequency of eating. The fasting diet may or may not involve a restriction in the intake of calories during non-fasting times.
There are a variety of fasting diets, sometimes called “intermittent fasting.” You may have read about:
- Time-restricted feedingMeals are consumed within a limited number of hours each day, with nothing consumed during the other hours.
- Alternate-day fastingEating is unrestricted every other day, and no or minimal calories can be consumed on the days in between.
- 5:2 eating patternEating is unrestricted for 5 straight days each week, followed by 2 days of restricted caloric intake.
- Periodic fastingCaloric intake is restricted for multiple consecutive days, such as 5 days in a row once a month, and unrestricted on all other days.
People With Type 1 Diabetes And Those With Type 2 Who Are Taking Insulin
IF may improve insulin sensitivity, and therefore may be beneficial for people with type 2 diabetes, but it can also be risky for people on diabetes medications associated with hypoglycemia , such as insulin and sulfonylureas such as glyburide, according to a study published in April 2019 in Nutrients. IF isnt recommended for people with type 1 diabetes, who rely on insulin. If you have type 2 diabetes and are curious about the diet, be sure to consult your healthcare team first.
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Is Intermittent Fasting Safe
Some people try intermitting fasting for weight management, and others use the method to address chronic conditions such as irritable bowel syndrome, high cholesterol or arthritis. But intermittent fasting isnt for everyone.
Williams stresses that before you try intermittent fasting , you should check in with your primary care practitioner first. Some people should steer clear of trying intermittent fasting:
- Children and teens under age 18.
- Women who are pregnant or breastfeeding.
- People with diabetes or blood sugar problems.
- Those with a history of eating disorders.
But, Williams says, people not in these categories who can do intermittent fasting safely can continue the regimen indefinitely. It can be a lifestyle change, she says, and one with benefits.
Keep in mind that intermittent fasting may have different effects on different people. Talk to your doctor if you start experiencing unusual anxiety, headaches, nausea or other symptoms after you start intermittent fasting.
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What Can You Eat On The 1: 8 Diet
- Whole grains: Rice, oats, barley, wholegrain pasta and quinoa.
- Protein: Meat, poultry, fish, eggs, nuts and seeds.
- Fruit: Apples, bananas, berries, oranges and pears.
- Vegetables: Broccoli, spinach and other leafy greens.
- Healthy fats: Olive oil, coconut oil, avocados.
The great thing about the 16:8 diet is that you can eat anything you want, within reason, but it’s important to choose whole foods and those high in vitamins during the eating period.
“Many people fail the 16:8 diet by packing in too many calories into the 8-hour period, often trying to get some in before the 8 hours ends, says Jenane. You should still be following a strict diet with a complete nutritional breakdown, to ensure you are consuming a targeted number of calories, not to mention macro nutrients and ensuring youre not consuming too much sugar.
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What’s The Evidence From Human Studies Of Calorie Restriction
Some study results suggest that calorie restriction may have health benefits for humans, but more research is needed before we understand its long-term effects. There are no data in humans on the relationship between calorie restriction and longevity.
Some people have voluntarily practiced extreme degrees of calorie restriction over many years in the belief that it will extend lifespan or preserve health. Studies on these individuals have found markedly low levels of risk factors for cardiovascular disease and diabetes. The studies have also found many other physiologic effects whose long-term benefits and risks are uncertain, as well as reductions in sexual interest and the ability to maintain body temperature in cold environments. These people generally consume a variety of nutritional supplements, which limits knowing which effects are due to calorie restriction versus other factors.
To conduct a more rigorous study of calorie restriction in humans, NIA supported a pioneering clinical trial called Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy .
In CALERIE, 218 young and middle-aged, normal-weight or moderately overweight adults were randomly divided into two groups. People in the experimental group were told to follow a calorie-restriction diet for 2 years, while those in the control group followed their usual diet.
Why Is Calorie Counting Important
Calorie counting helps you get a good idea of how much youre eating and what kinds of foods youre eating regularly. If you start counting your calories, youll likely start to see habits that have formed in regards to your eating style. From there, you can determine a plan of action that fits your health-related goals and workouts.
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