- Intermittent fasting is a popular weight-loss diet among celebrities, but so far research hasn't shown that it produces better results than eating regular meals.
- People who do intermittent fasting will restrict when or how much they can eat in a given period of time, like only eating within an eight-hour window each day.
- If you're interested in trying intermittent fasting, get the best benefit by cutting out late-night snacking. It'll help you eat more purposefully and get more sleep.
Intermittent fasting is a hot topic in nutrition and weight loss lately (Hoda Kotb and Jenna Hager Bush just started their first day of it), but the concept itself isn't new. In fact, temporarily going without eating or drinking stems from the practices of many major world religions and cultures. But intermittent fasting or "IF" — a trend gaining major traction among celebrities (Terry Crews! Jimmy Kimmel! Hugh Jackman!) and Silicon Valley — does things a bit differently for purported health, weight, and cognitive benefits.
While limiting your meal times can make your eating more purposeful, intermittent fasting is not a fit for everyone. Read on before you decide to start skipping out on snacks.
What is intermittent fasting?
Intermittent fasting generally describes a simple concept: You can eat pretty much whatever you want, but only during a specific period of time. There are few common schedules that IF proponents follow, according to the Journal of the Academy of Nutrition and Dietetics:
Time-restricted fasting: This schedule, which includes the popular 16:8 method, has you fasting for about 16 hours per day and eating within an eight-hour window. Most people do this by starting their fast at night, skipping breakfast, and eating their first meal around lunchtime. That gives them another seven or so hours to feed themselves until tomorrow.
Modified fasting: This option, commonly known as the 5:2 diet, allows you to eat about 25% of your recommended calorie needs on two fasting days each week and eat without restriction on the other five days.
Alternate fasting: In this less regimented style, you switch between periods of consuming zero-calorie beverages and actual eating. Some fans follow a high-fat or ketogenic diet on their days off from fasting. The fasts can end after less than 12 hours, while others can stretch as long as a full week! The Eat-Stop-Eat method, for example, calls for a 24-hour fast once or twice a week.
Does intermittent fasting work for weight loss?
Right now there are a few claims but not much by the way of science in favor of long-term fasting for health or weight loss. Alternate-day fasting did not help people lose more weight or keep weight off longer than people who simply restricted daily calories, according to a 2017 study published in the Journal of the American Medical Association.
The other bad news for fasting fans? LDL or "bad" cholesterol increased in the alternate fasting day group compared to control groups in a 2016 trial. Other risk indicators stayed the same across groups on this trial and other similar ones.
Some small animal studies have linked the intermittent fasting with reduced insulin production and sugar uptake in fat cells, leading to a lower risk of chronic disease. The thinking is that fasting may give your vital organs, digestive hormones, and metabolic functions a "break," but again, these studies were done on animals — not humans.
Is intermittent fasting safe long term?
Intermittent fasting plans can backfire tremendously — especially if your goal is to lose weight. Fasting can lead to nausea, dehydration, and even weight gain over time. No research to date has effectively looked at the long-term effects of fasting on metabolism. You may also eat more than you thought you would during your days or times of "feasting" too.
Eating real, nutrient-dense foods on a consistent basis fuels us physically, mentally, and emotionally. So if intermittent fasting works for you, go for it! But if it makes you feel anxious, depressed, or isolated in any way, it may not be the best plan for you personally.
Plus, I'd be remiss to mention who should absolutely not dabble in this eating style: Anyone who's previously struggled with an eating disorder or experienced disordered eating behaviors, or if you're immunocompromised, pregnant, lactating, or on insulin, oral hypoglycemic, or food-metabolizing medications. No matter who you are: Always check with your doctor before starting any new diet plan — especially one that includes fasting!
While research tells us that there may be potential benefits for some people, if severe food restrictions provoke any anxiety, then just don't do it. There's no clear-cut reason to opt out of meals, so stick with consistent eating strategies that work best for you — without any shame or guilt that extreme behaviors can stir up in so many of us.
Is intermittent fasting good for you?
What I like about intermittent fasting is that there may be benefits for some people to prolong (realistically) the time they go without food as it relates to sleep and caloric intake.
More purposeful eating: The biggest advantage of intermittent fasting stems from the fact many of us eat based on the scenario, not hunger levels. (Raise your hand if you've ever gone to the movies after dinner and suddenly wanted popcorn.) Through IF, you're limiting when you're allowed to eat, meaning you cut back on habit-driven snacking you may not have been aware of. Say you're a person who loves to graze during The Bachelor. If you're "fasting" post 8 p.m., you've automatically cut out munching opportunities — and subsequently, calories.
Better sleep habits: If your fasts are time-restricted, the lack of late-night snacking alone could help you go to bed earlier — a crucial component to any weight-loss plan. Getting seven hours of sleep per night has been linked to weight management, reduced risk of chronic disease, and improved metabolism.
Smarter food choices: Frequently choosing what and when to eat during a given day can leave us susceptible to making snap decisions that ultimately leave us dissatisfied — either immediately or when done consistently over time. But if you know you've only got a certain amount of time to eat, you may make smarter choices when you do. Simplifying and structuring the whole "what should I have for a snack?" scenario is a benefit many fasters appreciate.
How do you start intermittent fasting?
If you're considering IF, I'd encourage you to start small and simple: Experiment with an "early bird special" for dinner. Close your kitchen once you're finished, aim to get more sleep overnight, and eat a full breakfast at your usual time tomorrow. Making this one change is an aspect of intermittent fasting we can all get behind.
You Might Also Like