- Intermittent fasting is an eating pattern that cycles between periods of fasting and eating.
- Intermittent fasting does not change what you eat, but it does change when you eat.
- Intermittent fasting is a three-step process that includes the feeding state, the post-absorptive state, and the fasting state.
- Some benefits of intermittent fasting include reduced inflammation, balanced hormones, and lower blood sugar levels.
You may have heard a lot about intermittent fasting in the news lately, especially since celebrities like Beyoncé and Ben Affleck are supposed fans. The calorie-reducing fasting approach is said to promote weight loss and lower blood sugar levels. But, if you are new to the diet, and aren’t sure exactly what it does, here is a break down of the basics of intermittent fasting.
Intermittent fasting is an eating pattern that cycles between periods of fasting and eating.
Unlike like dieting, Sandra LaMorgese Ph.D. said that intermittent fasting is an eating pattern that cycles between periods of fasting and eating. LaMorgese said it doesn’t necessarily change what you eat, but she explains that it does change when you eat. It’s important to remember that intermittent fasting usually is a three-step process, she adds, and it typically includes the feeding state, the postabsorptive state, and the fasting state.
Intermittent fasting involves three states. LaMorgese said that the feeding state starts when you begin eating, and lasts for three to five hours as your body digests and absorbs the food you just ate. Next comes the postabsorptive state, which LaMorgese suggests is the state when your body isn’t processing a meal. This state lasts for eight to 12 hours after your last meal.
Finally comes the fasting state, which LaMorgese said starts nine to 12 hours after your last meal, depending on the size. This is usually the state when our bodies are in fat burning mode she said and is one of the reasons why many people who start intermittent fasting will lose fat.
The diet is flexible.
Registered-dietitian Kristen Mancinelli said that intermittent fasting is very flexible, meaning you can choose a daily time-restricted eating window, or fast on one, two, or three days per week. "One of the benefits of intermittent fasting is that it’s easy to do," Mancinelli tells INSIDER. "You don’t have to avoid particular foods or follow complicated rules."
This does not mean, however, you can binge eat unhealthy foods. Board-certified cardiologist Dr. Luiza Petre said that indulging in unhealthy food choices will just counteract the benefits you’ve achieved while fasting.
Its benefits can go beyond weight loss.
Karen Brennan, a board-certified holistic nutritionist at Tru Foods Nutrition Services LLC said intermittent fasting can help you avoid late night snacking, which ultimately helps balance insulin and blood sugar levels. She also said it reduces inflammation, regulates hormones, and regulates the feeling of hunger and fullness in the body.
Of course, more research is needed on this new diet trend to fully explore the reality of its benefits.
Intermittent fasting can aid in weight loss and help with jet lag.
If you are eating big meals and are also trying to lose weight, certified nutrition coach Esther Avant said you may be a good candidate for intermittent fasting, as she explains that a calorie deficit is required to lose weight, but that doesn't mean you have to eat like a bird. With a shortened eating window to take in your daily calories, she said you can still enjoy larger meals while still managing to lose some weight.
Those who are traveling across time zones may be good candidates for intermittent fasting, as Avant suggests that it can help with jet lag and cut down unnecessary travel expenses. The idea is to eat your first meal upon arrival when it's breakfast time at your destination. If you do decide to fast on your travels, she recommends staying well-hydrated the whole time you're fasting.
Intermittent eating is another option.
If you are a bit wary about trying out intermittent fasting, Brennan said you can try intermittent eating instead. This is usually an eight to 16 hour fasting period that does not restrict calories and helps the body shift to burning fat. She recommends starting out with a 12-hour fast and slowly increasing your fast time once you’ve become more acclimated to it.
Stay hydrated and avoid exercising when fasting.
No matter what kind of fasting window you choose, Toby Amidor, MS, RD, and author of Smart Meal Prep for Beginners, recommends staying hydrated at all times during fasting periods, as it is very easy to become dehydrated. She recommends drinking non-caloric beverages such as coffee, water, and tea while fasting.
Amidor also advises against any intensive exercise while exercising, as she said you need to fuel pre-workout and recover post-workout properly if you are exercising regularly.
Listen to your body.
If you’re new to intermittent fasting, Brennan suggests starting off with one to three days per week instead of fasting every day. And to maintain weight management after the weight loss you’ve achieved while fasting, she said that you may want to keep one day per week (or every other week) of intermittent eating as part of your normal routine.
During prolonged periods of fasting, you’ll definitely want to look out for any warning signs that indicate that the plan is not right for you, explains Amidor. These setbacks include irritability, lack of concentration, and dizziness. To avoid these unwanted complications, she suggests switching to shorter fasts instead of longer ones.
Sign up here to get INSIDER's favorite stories straight to your inbox.