Intermittent fasting is a new approach to eating that’s grounded more in fact than fad. It’s a flexible food plan for reducing your total calorie intake that uses the metabolic advantage of consuming little or nothing for part of each day — or for a day or two each week — to help you burn more fat, kick start weight loss and prevent chronic disease.
If that seems counterintuitive to everything you’ve been taught about nutrition, you’re right, but studies in both humans and animals are helping to prove what many people like me already know — that conventional dietary wisdom isn’t right for everyone and intermittent fasting can help. Here are a few potential benefits that are getting researchers’ attention.
Experts don’t recommend fasting if you’re pregnant or have an eating disorder, and anyone with diabetes should check with their doctor first, but because the plan is flexible, experts say it’s safer than fad diets and appears healthier for some people than typical diets.
Fasting periods should be at least 14 to 15 hours for women and 16 hours for men.
That can be as simple as not eating after dinner and skipping breakfast the following day — something busy days do for me without even trying — or you could opt for alternative plans like limiting calories to 500 or less every other day or for a day or two each week.
The most important part of the program is to give your body the time off it needs from food. How you do that is up to you.
I tried limiting myself to 500 calories every Monday and Friday but was an absolute bear by dinner time. In retrospect, I understand why my husband grew a sudden interest in working late twice a week.
I have friends that breeze through the day on 500 calories, but fasting for part of every day is what I do, and it’s nearly effortless now.
Two studies in humans back up what previous research in animals already discovered — that regular fasting and eating according to changes in circadian rhythm can optimize metabolism.
Scientists aren't sure why but suspect that modern society evolved faster than our bodies did and that returning to a more primal pattern of eating is what improves metabolic efficiency.
Sixteen hours without food is enough to induce mild ketosis and help you control cravings and burn fat, but if your first meal of the day is a bowl of pasta or chocolate cake, you may not see the benefits. This makes intermittent fasting a great partner for a keto-style diet, but the ketosis only lasts as long as you limit carbohydrates.
Research shows that fasting is at least as effective as other forms of calorie reduction for weight loss and for some may be a more manageable way to cut calories long-term, but if you overindulge on non-fasting days, the metabolic benefits alone may not be enough help you lose a significant amount.
The bottom line is that healthy eating rules when you’re not fasting still apply.
There are no human studies that guarantee you a six-pack if you fast. Any way of eating that controls blood sugar and improves your metabolism supports building muscle and decreasing total body fat, but it’s not a substitute for the gym.
A groundbreaking study in mice shows that overeating may throw a wrench in the body’s natural cancer-protective mechanisms and that fasting helps get those systems back in sync.
Add evidence that fasting decreases inflammation and oxidative stress in the body, and there’s hope that fasting could be a powerful tool for preventing cancer.
IBS is a tricky subject, and those unfortunate enough to suffer from it know there's no easy answer, but because fasting reduces inflammation, it's possible you'll see some benefit.
There are also limited studies suggesting that fasting can improve gastrointestinal motility and overall gut health, but it’s too soon to tell.
Evidence to points to fasting as one effective way to reduce cholesterol and triglycerides. Research is limited, and some conclusions are based on expectations that fasting will result in at least some weight loss, but studies support the idea that this type of diet helps control cholesterol and lowers the risk of heart disease.
After my son was born, I had a hard time losing the baby weight. My focus was on keeping my domestic jungle running smoothly, and personal nutrition wasn’t a top priority.
What I like most about intermittent fasting is that eliminating breakfast in favor of black coffee gives me more time for the kids in the morning and to plan better meals for the rest of the day.
My cravings for junk food are under control; I’ve lost the extra pounds and feel like I finally have enough energy to keep up with a growing brood.
Mainstream nutritionists aren't ready to give intermittent fasting a seal of approval yet, but most agree it shows promise, and it's flexible enough that almost anyone can give it a try.
It isn't for everyone, but traditional dieting wasn't helping me meet my fitness goals, and intermittent fasting did. Now, it's just the way I do life, and it works for me.
Interested in starting Intermittent Fasting today? Don't forget to take a look at my list of the best intermittent fasting books of the year.
Hi, I'm Kara! I am a stay-at-home mom with a 5-year-old son and a 3-year-old daughter. I enjoy getting lost on Pinterest, going to Starbucks, and baking healthy cookies. I’ve decided to share my love of fitness by building this site. I hope you enjoy your stay!