Does Intermittent Fasting Work For Weight Loss
Intermittent fasting is an eating pattern that has become popular among people looking to lose weight.
Unlike diets and other weight loss programs, it doesnt restrict your food choices or intake. Instead, all that matters is when you eat.
While some people claim that intermittent fasting can be a safe and healthy way to shed excess weight, others dismiss it as ineffective and unsustainable.
This article explains whether intermittent fasting works for weight loss.
Intermittent Fasting May Not Help You Lose Weight Faster Than A Standard Diet Year
Intermittent fasting is one of the most popular dieting methods out there. Search for it on instagram and you’ll find nearly five million posts under #intermittentfasting, and another 3 million under #fasting.
But a year-long study of 139 people in Guangzhou, China, suggests that intermittent fasting, where people limit the days – or times of day – that they can eat, may not be any more effective than simply reducing the amount of calories you take in.
The study, published in the New England Journal of Medicine, recruited volunteers aged 18-75 with a body mass index of between 28 and 45 and randomly sorted them into two groups.
For 12 months, each group was told to follow a calorie-restricted diet, limiting men to 1500-1800 calories a day, and women to 1200-1500 calories a day.
One group could eat whenever they wanted. The other observed a form of intermittent fasting known as time-restricted eating , and could only eat between the hours of 8 AM and 4 PM.
Both groups were supported during the year-long trial with diet coaching and nutritional shakes for the first six months.
You Arent Sleeping Enough
Few studies have looked at the direct correlation with weight loss and sleep while following an intermittent fasting plan, however in general,several studies have shown a connection between adequate sleep and positive weight loss outcomes, says Smith.
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How to fix it: You’ve heard it before, but, Make an effort to sleep at least 7 hours per night, says Smith.
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Whats The Best Protocol For Weight Loss
When it comes to weight loss, there is no best protocol the best protocol is one you can stick with. You might want to keep your fasting window to a minimum. Or, you may prefer fasting for the majority of your day.
Common intermittent fasting protocols are:
- The 16:8 Method: Fast for 16 hours and eat all of your days food within eight hours, seven days a week.
- The 23:1 or One Meal a Day Diet: Fast for 23 hours and eat one meal a day in a one-hour window.
- The 5:2 or Fast Diet: Eat as you typically would for five days and limit daily calories to 500-600 for two days in order to fast.
- Eat, Stop, Eat: Similar to the Alternate Day Fast, but you choose to fast for an entire day once or twice per week and return to your routine eating habits the other days.
For an in-depth look at the various types of intermittent fasting protocols, check out this guide to learn more about which regimen might fit for you.
Most Common Reasons Intermittent Fasting Doesnt Work For Weight Loss
As you consider if intermittent fasting really works for weight loss, lets look at some common issues that make intermittent fasting difficult and then, we will discuss how to overcome them.
Mood Swings
One woman was telling me she started snaping and losing her cool when she was intermittent fasting. Thats what we call becoming hangry, an explosive combination of angry and hungry.
When you havent eaten for a while, the level of sugar in your blood decreases, she explains. When your blood sugar gets too low, it triggers a cascade of hormones, including cortisol and adrenaline . These hormones are released into your bloodstream to raise and rebalance your blood sugar.
Chronic Stress
In the same vein as feeling hangry, chronic stress can complicate intermittent fasting. Stress, which causes the release of cortisol, is not a bad thing. In fact, cortisol has many benefits, including reduced inflammation and fat loss. The problem is when your body experiences too much stress. Too much cortisol will cause weight gain, depression, and irritability.
Hypoglycemia
Some women have come to me saying they have hypoglycemia. When your blood is 70 milligrams per deciliter or lower, you start experiencing symptoms such as:
Keep in mind that nondiabetic hypoglycemia is extremely rare.
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What Should I Eat After 16 Hours Of Intermittent Fasting
Try balancing each meal with a good variety of healthy whole foods, such as:
- Fruits: Apples, bananas, berries, oranges, peaches, pears, etc.
- Veggies: Broccoli, cauliflower, cucumbers, leafy greens, tomatoes, etc.
- Whole grains: Quinoa, rice, oats, barley, buckwheat, etc.
- Healthy fats: Olive oil, avocados and coconut oil.
How Long Does Intermittent Fasting Take To Show Results
You might begin to first notice a difference in your body about 10 days after you begin intermittent fasting. It could take between 2-10 weeks for you to lose significant weight. You might lose up to a pound each week.
Usually, the first signs you will notice that scream that your intermittent fasting is working is less bloating. Your midsection might look trimmer just over your first week of intermittent fasting.
Observing weight loss will take a little longer as your body needs some time to adjust to this new diet.
At about the second week is when most people first notice that they have dropped their first few pounds. If you have still not lost any weight by week two, stay consistent for about four or five more weeks and your results should come in soon enough.
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How Does Intermittent Fasting Help You Lose Weight
Shorter eating windows is what make intermittent fasting an effective weight loss aid. Since youre eating in a smaller window of time, this can help you reduce your calorie intake if you dont overcompensate by eating more than needed. Eating fewer calories is what could ultimately help you lose weight over time.
Why 3 Pm Is A Key Time To Start Eating Less Food
Peeke also recommended that I stick to having lunch be my biggest meal of the day. Theres a study that a majority of Americans eat over the course of 15 to 16 hours out of the day, with the majority of their calories coming after 3 p.m. Its a recipe for disaster, she says, referencing a study published in November 2015 in Cell Metabolism.
Peeke suggested that rather than having my banana protein shake as an evening dessert and not eating anything before exercising, I instead drink it first thing in the morning. This way, the carbs from the banana would give me an instant source of energy to fuel my workout and my body would be processing the carbohydrates at an optimal time of the day.
The switch immediately paid dividends. I had way more energy throughout my workout. Because my body was working at a higher intensity, I was burning more calories than I would be even if Id been doing fasted cardio. Peeke recommended that I try to stay under a 12-hour window of restricted eating, but I was able to manage my dinnertime to keep my eating in a 10-hour window. Although my weight drifted up by 2 lb, it was because I was adding muscle mass instead of fat. The additional muscle in my arms and shoulders were noticeable. And as my body fat percentage got lower, I started to see some veins popping out of my biceps, forearms, and calves.
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She Knew What Worked Before Was No Longer Feasible
After her first pregnancy, Etienne-Mesubi had lost weight by running and modifying her diet. She trained for 5ks, 10ks, and half marathons, and she watched everything she ate.
I was in that diet mentality. I thought, I cant have this, I cant have that, I dont want to gain weight. Looking back, it was really not a good place for me with food. I was obsessive about everything I was eating and all the exercise I was doing, she says.
She didnt see a path forward for weight loss. In my mind there was no way to do it except the way I did after my first daughter, and I was not feeling that energy, she says. I thought, Im older, we have two kids now, and Im tired. Theres no way Im running anywhere or doing any HIIT exercises, she says.
On Instagram she came across people who were losing weight with intermittent fasting and tracking their progress with the LIFE Fasting Tracker app. I didnt know what that meant. I thought people were just not eating. How do you not have breakfast or lunch? I couldnt grasp the concept, she says.
With a Ph.D. in epidemiology, Etienne-Mesubi put her research skills to work learning about intermittent fasting: I needed some science. I wanted to know what evidence existed to show this was a legit way to lose weight.
Does Intermittent Fasting Work
IN THE DIET WORLD THESE DAYS, intermittent fasting may be a popular trend, but those trying to lose weight or improve their overall health should know that it can be a hard plan to stick to.
The approach alternates between periods of fasting and non-fasting during a particular time period. Intermittent fasting isnt about deprivation, but about splitting up your calories differently than the three-square-meals a day plus a snack routine.
The reason intermittent fasting is thought to be effective in weight loss is because it increases your bodys responsiveness to insulin. Insulin, a hormone that is released when you eat food, causes your liver, muscle and fat cells to store glucose. In a fasting state, blood glucose levels drop, which leads to a decrease in insulin production, signaling your body to start burning stored energy . After 12 hours of fasting, your body runs out of stored energy and begins burning stored fat.
Three of the more well-known IF plans are:
- 5:2 diet: Eat normally, but healthfully for five days of the week and consume only 500 to 800 calories on two nonconsecutive days. Women usually aim for closer to 500 and men around 800 calories. Some might opt to split their calories into two or three mini meals.
- Alternate days: Eat normally one day, then fast the next, and repeat for the rest of the week.
- Time restricted fasting: fasting every day for 12 hours or longer.
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Rules Of Intermittent Fasting For Weight Loss
Lets be honest: I dont like rules! I get so frustrated when health experts say dont do this, dont do that, or when they act as if they have found the ultimate solution that will work for everyone. Or worst, when they make up a list of rules to follow and make simple things sound complicated. At the same time, I understand that for some people, having rules to follow is helpful. They can act as guidelines to ensure success whenever trying something new. Thats what I was envisioning when I wrote these rules of intermittent fasting for weight loss.
Looking At The : 2 Diet
One of the better-known intermittent fasting diets is the 5:2 plan.
Under this plan, you eat what you want for 5 days each week and then limit yourself to 500 calories on the other 2 days.
In a recent study conducted at Queen Mary University of London, researchers said the results of 5:2 intermittent fasting are similar in effectiveness to traditional dieting.
They also found, however, that people generally preferred intermittent fasting and were more willing to stick with it.
The study included 300 adults with obesity 100 received information on conventional dieting, 100 received information on intermittent fasting, and 100 received information on intermittent fasting along with 6 weeks of support.
The researchers followed participants for a year, noting weight loss. At the end of the study, they noted:
- Fifteen percent of participants in the group provided with information on traditional dieting lost at least 5 percent of their body weight.
- Eighteen percent of people given information on intermittent fasting lost at least 5 percent of their body weight.
- Twenty-eight percent of people who received information on intermittent fasting as well as 6 weeks of support lost at least 5 percent of their body weight.
While weight loss was similar in the groups, the number of people who lost weight increased with intermittent fasting.
Researchers said the two groups who used the 5:2 diet had a more positive experience than people using the traditional diet.
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Intermittent Fasting For Weight Loss
Social channels are filled with reports of significant weight loss using intermittent fasting. Studies show efficacy, too, but the reported weight loss is frequently much smaller.
One difficulty with assessing the scientific support for intermittent fasting for weight loss involves comparing different fasting protocols. For instance, some studies evaluate time-restricted eating with daily fasting windows ranging from 14 to 20 hours. Others investigate alternate-day fasting, while others focus on severe caloric restriction to mimic fasting physiology.
Another issue is factoring in the baseline diet followed by study subjects. Are many of them eating a high-carb standard Western diet? Or are they eating a low-carb, high-protein diet? The difference may matter as those eating low carb and/or high protein may find fasting easier, and thereby stick with it longer to see greater healthy weight loss benefits.
Despite the discrepancies, most fasting interventions show benefits for weight loss.
One meta-analysis of randomized controlled trials looking at time-restricted eating found an average weight loss of 4.4 pounds in up to 12 months.2 While the absolute weight loss may not be much, thats still pretty impressive considering that participants didnt change what they ate. They only changed when they ate.
So its safe to say that intermittent fasting has the potential to help people lose a little weight.
Can Intermittent Fasting Help You Lose Weight
By Elizabeth Levinson, MDVirtua Family Physician
Americans are always looking for the best, most effective form of weight loss. Thats why the diet industry is a multi-billion dollar business. But diet crazes and fads come and go, and many of them arent effective in the long term. The most recentintermittent fastingis an eating pattern that involves regular, short-term fasts, or periods of time when you eat few or no calories.
Intermittent fasting is receiving attention from the media as it becomes popular amongst celebrities. Supporters say that it promotes weight loss or weight maintenance while helping maintain muscle mass and control insulin levels.
While intermittent fastingalso known as the IF or fast dietis trendy, you might wonder if it actually works AND is safe.
Read Also: Tips For Starting Intermittent Fasting
Why You May Not See Results
Although there is research supporting the effectiveness of intermittent fasting, there are many reasons you may not see results. It may sound counter-intuitive, but you may not be eating enough calories during your fasting window. If you severely restrict calories, it can backfire. Sudden under-consumption can lead to metabolic adaptation, a process where your body becomes more efficient at using energy and storing fat which means youll burn less calories. The goal is not to count calories and cut them, its to eat minimally processed, nutritious foods during your eating window until you are full.
If you eat ultra-processed, energy-dense foods during your meals, that could be another reason why youre not getting the results you desire. Fasting can help you burn fat, but it doesnt mean that its magic! Remember to fill your plate with lean proteins, complex carbs, and healthy fats.
Finally, make sure you drink plenty of water during your fasting window. Hydration helps you feel full and satiated, and its easy to mistake thirst for hunger. If youre not hydrated when you approach your eating window, you may be prone to choose and eat ultra-processed foods.
The Unexpected Benefit No One Talks About
Lost amid the talk of IFs various health benefits is a very real secondary perk: saving money. When you cut your diet down to one or two meals per day, your food costs drop accordingly. Its impossible to say exactly how much you stand to save, because it depends on how often you dine out, what you buy at the grocery store and so on.
But even if your total food expenses drop by just 25%, thats a huge difference. Suppose you typically spend, say, $100 per week on food. If you subtract the cost of seven meals per week, that might realistically lower your expense to $70. Over the course of one month, youd save $120. Over one year, $1,440.
Thats a vacation. A down payment on a new car. And theres a bigger-picture benefit as well: Youre lowering your impact on the planet. Imagine if entire populations switched to two meals a day from three. We could get by on fewer crops and animals, which in turn would reduce overall water consumption. Maybe thats a bit of pie-in-the-sky thinking, but theres truth to it.
Read more:Impossible Burger vs. beef: Which is better for the environment?
I mention all this because after I started IF, I noticed I was spending less on food. And then I started thinking about the external benefits of less food consumption, and that made me feel even better about it. Eat less, help the planet. Win-win!
More recently, I realized it also means fewer trips to the grocery store and carry-out restaurants, meaning less chance of exposure to the coronavirus.
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