Nixing meals and decreasing caloric intake may seem easy, but read this before you dive into an intermittent fast.

Intermittent fasting is an eating pattern where you cycle between periods of eating and fasting. Johns Hopkins Medicine neuroscientist Mark Mattson, Ph.D., who has studied the health impact of intermittent fasting for 25 years, and adopted it himself about 20 years ago, said in The New England Journal of Medicine that "intermittent fasting could be part of a healthy lifestyle." He claims research supports that reducing your "eating window" can help decrease your risk of chronic diseases and increase your longevity.

Think you're ready to embark on an intermittent fast? Spacing out meals and snacks may sound simple enough, but you can easily sabotage your fast by making these mistakes.

plate with knife and fork forming what looks like clock arms with food only within those arms (at 12:00 and 5:00)
Credit: Getty / lacaosa

1. You don't ease into it.

Skip breakfast. Skip lunch. And by 3 p.m. you're willing to eat your arm. "If you normally eat every three to four hours and then suddenly shrink your eating period to an eight-hour window, you'll likely feel hungry all the time and discouraged," according to Libby Mills, RD, a dietitian at Villanova University's College of Nursing. "Deciding to limit your eating hours may be motivated by weight loss. However, this represents an opportunity to reacquaint yourself with what your body is really feeling. We often are eating every three to four hours and not always because we are hungry."

Plus, you don't have to fast all week. In fact, people who follow the 5:2 diet eat regular amounts of healthy food for five days, then flip the switch on the other two days, by reducing caloric intake. A study involving 107 overweight or obese women found that women who restricted calories twice weekly lost the same amount as those who continuously cut calories.

2. You are consuming too many calories.

You're not alone, according to Mills. "It can be easy to overeat when a fast breaks, either because you're feeling ravenous or you justify to yourself that you're making up for lost calories." She advises to use a scale of 0 to 10, where 0 is famished and 10 is stuffed. You should feel hungry before eating and you should stop eating when you're full, not just to clean your plate. She also recommends slowing down while eating so your brain has time to signal when you're getting full. "It may take 15 to 20 minutes after you start eating," Mills notes.


Recipe pictured above: Greek Burgers with Herb-Feta Sauce

3. You sabotage with soda.

Mills says the carbonation in soda can mask your sense of hunger, which can set you up for being too hungry at your next meal and lead you to overeat. "Artificially sweetened drinks can also raise the satisfaction bar for sweet tastes, so when you do eat a piece of fruit it may not be satisfying."(Learn more about what artificial sweeteners do in your body.)

She adds these beverages may also have caffeine, which can affect people differently. "Some caffeine may make you jittery and set you up for craving sweets. While other caffeine may mask your sense of hunger and postpone eating until well past feeling hungry."

4. You aren't keeping track of your water intake.

Watermelon, Cucumber & Feta Salad

In general, you should be drinking 2 liters (that's 1/2 gallon) of water per day, "Water is a part of metabolic reactions in our body and is necessary for it to function properly. Hydration prevents us from mistaking hunger for thirst," Mills notes.

During snack breaks, opt for nonstarchy veggies and fruits that contain water (yep, hydrating foods count towards your daily water goal!). Have sliced cucumbers, celery, watermelon and oranges prepped in the fridge or your lunch bag.

5. You're not eating the right foods when you break your fast.

Mills says eating adequate lean protein (such as meat, poultry, fish and plant-based proteins like legumes), nuts and seeds with each of your meals will help keep you full longer. "Protein helps us feel full. Plus, if you are losing a few pounds, protein will help maintain your metabolically active lean body mass."

According to Mills, another perk is that fiber from fruits, vegetables, whole grains and legumes will slow the digestion and absorption of the carbs you eat, so you stay full and energized longer between meals. "Plus, choosing foods that provide protein and fiber will provide you with the vitamins, minerals and nutrients you will need as you re-portion your calorie intake."

6. Your approach is way too extreme.

Sure, you want to grab this diet trend by the lapels and run with it, but there's no need to starve yourself. Taking in less than 800 calories per day will cause greater weight loss (with significantly increased hunger), but also greater bone loss. That's not healthy—or sustainable—in the long term. Not to mention, if you make your windows of not eating too long, you won't be able to stick with it. Make smaller, manageable changes and always listen to your body.

7. You're having caffeine withdrawals.

to go cup of coffee
Credit: Grove Pashley/Getty Images

Who said to ditch your morning joe, afternoon espresso or warm tea? No one! In fact, coffee isn't bad for you. Mills says, "A caffeinated beverage, especially if warm, is a comforting bridge between meals." Remember, no adding sugar or milk if you drink your cup when you're fasting.

8. You're in your own head.

Whether you stick with intermittent fasting for a week or a month, it needs to feel like a natural part of your routine. "Shifting the focus to being more intuitive about when you eat based on your sensation of hunger and fullness is something that makes sense for a lifetime," Mills says. "Choosing foods that nourish your body with the nutrients it needs to stay energized changes a calorie-counting mindset to a quality of life focus." It's less diet mode and more a new way of thinking about—and consuming—food.

9. You engage in an intense, hardcore workout.

You can exercise, just not like the Hulk. It's hard to go all out in a workout if your tank is empty. Moderate exercise is important for health benefits, but if you want to go a little more hardcore, make sure you're not hours away from your next meal. Basically, don't hit the gym at 5 a.m. and then not break your fast until 2 p.m. Your body needs fuel to get you through a tough workout and to replenish your stores after one.

10. You give up because you ate at the wrong time.

Don't throw in the towel, and don't beat yourself up. You won't undo all your work with one meal, but you might with a bad attitude. Take the time to reassess and make sure the schedule you've set up continues to work with your lifestyle. Maybe it doesn't anymore and you want to shift your eating window or relax it a bit. That's OK. Also, remember to focus on your food choices and eat as many high-quality, nutritious foods as possible. If you have the right balance of protein, fiber, nonstarchy veggies and H2O, you won't be hungry throughout the day.