Intermittent Fasting: Your Break from Calorie Counting

What seemed to be the latest weight loss fad a few years ago may actually be a formula for weight loss success for some. What is this "fad-turned-fact?" Intermittent fasting.
How could a weight loss diet be successful when it combines several "feasting days" where food is consumed abundantly, along with "fasting days" where calories are severely restricted? That's right: Fasting days contain only 500-600 calories. It would seem that this eating pattern would bring about excessive hunger, resulting in binge eating when food was finally permitted.
Yet, people regularly express the need for a break from the humdrum and mundane calorie-counting world. Could intermittent fasting be the break that lowers your weight?

What Is IF? 

A variety of IF programs exist, including those in which individuals consume calorie-producing foods and beverages for just four to six hours each day and other that include two days of very low calorie consumption alternating with five days of "normal eating." Other IF plans require individuals to eat just one meal every other day, which contains about 30 percent of their typical daily calorie intake. 

Several studies now compare the weight loss results of an IF eating plan to a more traditional calorie restriction (CR) diet plan. Most of these studies used an IF program of two to three days of low, 500 to 600 calorie intake, alternating with four to five days of normal eating. In the studies, similar weight loss results were reported with both IF and CR eating plans showing both to be equally effective in decreasing body weight and body fat.

How IF Works

With only two to three days a week of consuming fewer calories, some find it to be an easier plan to follow. As a result, the caloric intake stays low and weight loss increases. There is also the possibility that the continued daily caloric restriction of many traditional weight loss plans may actually slow metabolism. Eating normally most days of the week, combined with two or three days of fasting may be more effective at keeping the metabolic rate consistent.
Lastly, glucose is available in the blood and glycogen stores are filled in the muscles and liver in a traditional weight loss plan, thus the body relies less on stored fat. However, on fasting days when glucose is not as readily available, the body turns more quickly to fat as a fuel source.

What Science Doesn't Say

While there is preliminary research showing that intermittent fasting can be a reliable plan for weight loss, it is important not to get caught up in all the other claims being touted. Magazines, books, celebrities, chefs, documentaries and some doctors are reporting all sorts of miraculous cures as a result of IF. You'll see reports of stimulating fat burning, boosted metabolism and increased energy, but it's all just slick marketing. Weight loss is weight loss—with IF, you are primarily just cutting out excessive calorie intake. You'll also hear claims regarding IF and longevity, cancer cures and dementia treatment. While preliminary research is occurring in these other areas, we are far from having enough research evidence to make medical treatment recommendations.

Is IF for You?

First, establish if IF is not for you. Medical conditions such as diabetes require a more equal distribution of food intake or use certain medications that require specific food intake patterns. Furthermore, if you are involved in an intense athletic training program, are pregnant or planning to become pregnant in the future or you have or are recovering from an eating disorder, IF likely is not the eating plan for you. Consider making a quick call to your doctor or Registered Dietitian Nutritionist (RDN) to get the green light before starting an eating program.
If your current calorie-counting plan works for you, keep on keeping on. If, based on your physically demanding job or lifestyle, you know that there is no way you could survive on 500 calorie intake days, you are probably right. You know your body best, so follow your gut.
However, if you are thinking that IF might work for you and your goals and you're tired of counting every calorie, every day, this might just be the break you need.

IF, The Smart Way

If you want to try an IF program, then fast wisely. First, you need to know your Sparkpeople weight-loss calorie range and weight-maintenance calorie amount. For example, let's assume that you lose one pound of weight each week on a 1,500 calories-per-day plan, and you maintain your weight on 2,000 calories per day.
Set the calorie amount for your two days of lower-calorie fasting by using about 25 percent of your maintenance calorie amount for your fasting days. If that 2,000 calories per day maintains your weight, aim for 500 calories. The amount that is often suggested is 500 calories for women and 600 calories for men. Very light meals, three to four times a day will bring you to this calorie amount. The chart below includes a few light meal ideas.
Remember to use water and zero-calorie beverages to meet your hydration needs, and consider taking a multivitamin-mineral supplement.
Examples of 150-calorie meals for fasting days  (pick 3-4 daily)
1 cup skim milk and 1 small piece of fruit
6 ounces light yogurt and 1 cup berries
½ cup cooked oatmeal and ½ cup canned peaches
Omelet made with 2 egg whites, 1 slice lowfat cheese, and 2 cups sautéed non-starchy veggies
½ cup fat-free cottage cheese and ½ cup pineapple
1 cup vegetable or minestrone soup, and 1 piece of fruit
3 cups leafy green salad, topped with 3 ounces canned tuna and 1 T. low-calorie dressing
3 cups leafy green salad, topped with 3 ounces deli turkey breast and 1 T. low-calorie dressing
3 ounces baked tilapia and  1 cup roasted carrots and broccoli
3 ounces grilled skinless chicken breast and 1 cup sautéed summer squash and zucchini
3 ounces roasted pork tenderloin and 1 cup tomatoes, cucumbers and bell pepper strips
It's important that you change the way you think about your five "normal" days of eating. Rather than "feasting days," think of the five days as "feeding days." Focus on using your allotted 1,800 to 1,900 calories to give your body the lean meat and vegetable protein foods, fruits, vegetables, low-fat dairy and whole grains it needs.
Not having to meticulously count calories is one of the main benefits of an IF eating plan, but you still have to maintain an overall healthy, balanced eating plan.

Monitor Your Progress

Trial your IF program for two to three weeks. Monitor how you are feeling and your weekly weight loss.  Tweak your program along the way so that you continue with your calorie deficit without feeling dizzy, light-headed or fatigued. If you continue to struggle with these symptoms, face the facts that IF is not for everyone.
As you continue with your IF plan, decide if this is a long-term eating style or one you use only for short time periods to add variety and flexibility to your plan. Ask yourself if IF is helping you to be more successful in achieving your weight-loss goals and gauge whether or not you feel more or less deprived when using an IF plan. No matter what plan you choose, continue to be aware of all food choices and mindfully eat your meals and snacks.
Click here to to redeem your SparkPoints
  You will earn 5 SparkPoints

Member Comments

interesting article and very interesting comments Report
I'm in week two of intermittent fasting. I'm using the 16:8 plan and eating from 10:00 a.m. to 6:00 p.m. I don't like to eat late in the evening so this seems to be working pretty good for me. I do get a little hungry in the morning but I think it's just getting adjusted to having breakfast a little later. Drinking water helps and limiting coffee to one cup also helps. I'm not a huge calorie counter but have been trying to journal my food intake daily. I just stay away from refined sugar and processed foods, and don't eat much bread or pasta. So I try to eat mostly fruits, veggies, fish, and some chicken. For snacks I like to have things like frozen pomegranate seeds and green olives, fresh veggie sticks, or half a banana with a little cacao powder. It's early yet but so far I like having a specific eating window. Report
thanks for sharing Report
I have high blood pressure and I truly do not believe in fasting IF or anything else some call it. I do believe in the safe plan of Spark and have been on it since 2011, Sure I have my up and down days but who hasn't? I will stick with SP Thank you. Report
@sandlewood108 comment is "right on." Report
I suffer from low blood sugar, so I cannot fast. I have tried, but I get dizzy and get severe headaches. To avoid these symptoms, I have to eat every 4-5 hrs without fail. Report
I went on an IF, modified keto, restricted calories diet of my own creation (~1200-1300 calories) nearly 15 mos ago. To date, I have lost 112 lbs, lowered my HgbA1C from 6.1 to 5.2; my FBS from 117 to 89; my total cholesterol from 276 to 182, my triglycerides from 291 to 103; & my Total/HDL ratio from 4.6 to 3.3 and the higher pre-diet lipid results were WITH a statin, while the post diet results are WITHOUT one! .

The IF I did was to fast for 18-20 hours/day & consume ~1200-1300 calories within the remaining 4-6 hours. The modified keto portion was:
- 60% fats, the VAST majority of which were healthy fats with only ~15-20 gm (10-15% of calories)
- 30% protein
- 10% net carbs (total carbs minus fiber), the vast majority from high nutrient, high volume, low calorie vegetables & fruits; NO starches, sweets/desserts, processed foods except on my ONE cheat day per month!

I really wasn't ever truly hungry; only had cravings when I saw/smelled something on the No-No list!!

I also slowly increased my exercise. Now that I have reached my goal, I am focusing on strength training, cardio, & flexibility. I am also slowly reducing my fats, increasing my carbs, and increasing my calories; I am now at 1600-1800 calories, 50/35/15, fats/protein/net carbs, & adding in some higher density, higher carbs/calories veggies such as beans, although sparingly.

This type of IF works for me & my lifestyle and i intend to continue with it as a permanent lifestyle change. The higher fats & protein with lower carbs is also a permanent change, although not as extreme. I do not see my going back to the so-called "healthy diet" that is predominantly carb-based. That diet causes me to gain weight and elevates my sugar & lipid levels, increasing my risk of several health issues. While it may be healthy for many, even most, it is not for me! Report
Thanks Report
Thank you Report
great info Report
Interesting article Report
I have begun IF again and eat healthy foods. I am 60 and it has really helped me lose weight and feel good. I am reading Naomi Whittel's book now (Glow15) to learn more about the benefits of Autophagy and IF. I really dontcount calories, but instead try to balance fats, proteins, and good carbs. Report

About The Author

Becky Hand
Becky Hand
Becky is a registered and licensed dietitian with almost 20 years of experience. A certified health coach through the Cooper Institute with a master's degree in health education, she makes nutrition principles practical, easy-to-apply and fun. See all of Becky's articles.