Intermittent fasting: a weight loss solution for busy physicians?

 

I noticed this year’s Medscape Physician Lifestyle & Happiness Report (2018) included information regarding which physicians wanted to lose weight (47% of physicians surveyed expressed that they want to lose weight), whether more women or men wanted to lose weight (52% of women physicians versus 45% of men physicians wanted to lose weight), and the percentage of physicians who exercised regularly (35% of physicians reported they exercised 2-3 times a week). This got me thinking about how it might be challenging for busy physicians, to make time for exercise and healthy eating. It wouldn’t be far-fetched to imagine a scenario in which a physician gained a few pounds during a particularly busy period in life, while juggling her career, marriage, and children, all while trying to nurture healthy habits.  

 

Not too long after I read that Medscape report, I came across the concept of intermittent fasting. “Fasting” can mean many things to many people. The word fasting initially conjured up thoughts of painstaking and unpleasant self-deprivation, and it didn’t sound healthy. Some anorexics have been known to describe their non-eating behaviors as “fasting.” Yet, on the other hand, my pious and trim maternal grandmother has fasted every Tuesday for the last 40 years. For her, fasting on Tuesdays is eating only fruit and drinking water before the sun comes up and then abstaining from eating and drinking until the sun goes down again. Similar to the Catholic concept of giving up something for Lent, this once a week fasting exercise helps my grandmother connect with her spirituality and bring herself into a spirit of mindfulness, gratefulness and prayer, while acknowledging all her blessings. I didn’t have negative associations with this type of religious fasting. Rather, I’ve always respected my grandmother’s discipline. Then there is my dad, a busy internist with so many patients per day that, quite often, he simply doesn’t have enough time to eat multiple meals. However, he generally touts going through the day without eating much as something he’s proud of because it helps him limit his caloric intake and maintain his weight. With all these associations swimming around in my head regarding fasting, I was intrigued, and since I was trying to lose a few pounds before my wedding, my curiosity compelled me to, at least, do my own research about intermittent fasting. Was there something to fasting after all?

 

Intermittent Fasting

Intermittent fasting is the concept of fasting for 14 to 16 hours and eating during the remaining 10 or 8 hours (14:10 or 16:8). The goal is to help people consume less calories while optimizing some hormones related to weight control. In addition to the above strategies, there are other ways to do intermittent fasting: the Eat-stop-eat method (do one or two 24 hour fasts per week, i.e. not eating from dinner one night until dinner the following night, aka eating one meal a day); and the 5:2 diet (only eat 500-600 calories on two days a week, but eat normally the other 5 days). As long as people don’t eat much more than usual during meals, when it’s a feeding time, these strategies should help people reduce daily caloric intake, resulting in reduced belly fat and overall weight loss.

 

Intermittent Fasting affects hormones and may hasten fat burn and weight loss

Fasting has consequences on the hormonal state of the body. The main hormones affected by fasting are insulin, human growth hormone (HGH) and Norepinephrine.

Fasting causes insulin to decrease (eating increases insulin) and lower levels of insulin facilitate fat burning.  HGH may have up to a five-fold increase with fasting; among other things, growth hormone aids in fat loss and muscle gain. The nervous system releases norepinephrine during a fast, and this hormone causes body fat to break down into free fatty acids that can be burned for energy. Although, recently, some dieticians popularized the weight loss benefits of eating 5-6 small meals to “keep the metabolism revved up,” fasting for relatively short periods of time may actually increase fat burn. However, fasting for long periods of time (over 48 hours) can suppress metabolism. This idea may have led to the popularization of the concept of not eating too few calories (or consuming below your BMR) lest you go into “starvation mode,” which really doesn’t happen unless you fast for over 48 hours.

 

Intermittent fasting makes caloric restriction easier

Eating fewer calories than you burn has been a proven strategy for weight-loss. Many studies have found that on average, diet has more of an impact on weight-loss than exercise. Sticking to a low calorie diet is easier said than done because it requires calorie counting. With intermittent fasting, the weight loss does not require calorie counting because the feeding timings mediate an overall reduction in caloric intake, naturally, by skipping meals during the fasting times. In addition to the short-term hormonal changes propagated by intermittent fasting, people on this plan lose weight because they are eating less calories per day. A 2014 review by Barnosky et al. found that intermittent fasting reduced body weight by 3-8% over a period of 3 to 24 weeks. People lost about 0.55 pounds per week with intermittent fasting. The subjects also lost 4-7 % of their waist circumference, suggesting that they lost belly fat. These results show that intermittent fasting can be a useful weight loss tool.

 

Intermittent fasting helps maintain muscle tone

One of the negative consequences of dieting is that it might lead to decreased muscle mass along with decreased fat. A 2011 review by K.A. Varady found that intermittent calorie restriction (as in intermittent fasting) led to the same amount of weight loss as continuous caloric restriction (a traditional diet), but with less loss in muscle mass.

 

My Conclusions

Reading all this about intermittent fasting certainly sounded compelling, so much so, that I decided to try it for myself. It’s only been a week so far, but it has not been too difficult. It’s much easier than counting calories, grams of carbs, or grams of protein. Since I am also strength training these days, I was eager to find an eating plan that may help me maintain muscle mass while still restricting overall calories for my weight loss goals, and, preferably, one that did not force me to eat a crazy protein to carbs ratio. Intermittent fasting works for me so far!

 

Is this a weight loss solution for busy physicians?

It sounds quite likely that it would be effective. In fact, it seems like my dad was doing intermittent fasting all along all these years when he would eat a late “lunch,” at 3 pm, consisting of a danish from a box of pastries that one of the nurses brought in and one banana, which he grabbed from a conference, followed by a well-balanced home-cooked dinner in front of the TV late in the evening. He would have only been eating from 3pm to 11pm (8 hours). While it’s not for everyone, because of its customizability, intermittent fasting does sound like a convenient eating plan for anyone with a busy schedule, physicians and patients alike!

Meghana Agni

DUCOM 2018

 

For more information about Intermittent Fasting, visit Intermittent Fasting 101 — The Ultimate Beginner's Guide:

https://www.healthline.com/nutrition/intermittent-fasting-guide

 

Sources:

Barnosky AR, Hoddy KK, Unterman TG, Varady KA. Intermittent fasting vs daily calorie restriction for type 2 diabetes prevention: a review of human findings. Translational Research. 2014;164:302-311.

Gunnars Kris. How intermittent fasting can help you lose weight. Authority Nutrition on Healthline. https://www.healthline.com/nutrition/intermittent-fasting-and-weight-loss. June 4, 2017. Accessed April 17, 2018.

Santos HO, Macedo RCO. Impact of intermittent fasting on the lipid profile: Assessment associated with diet and weight loss. Clinical Nutrition ESPEN. 2018;24:14-21.

Peckham, Carol. Medscape Physician Lifestyle & Happiness Report 2018. Medscape. https://www.medscape.com/slideshow/2018-lifestyle-happiness-6009320#20. January 10, 2018. Accessed April 17, 2018.

Persynaki A, R.D, Karras, Spyridon, M.D., Ph.D, Pichard, Claude, M.D., Ph.D. Unraveling the metabolic health benefits of fasting related to religious beliefs: A narrative review. Nutrition. 2016;2017;35:14-20.

Varady KA. Intermittent versus daily calorie restriction: which diet regimen is more effective for weight loss? Obesity Reviews. 2011;12:e593-e601.