An RD's Experience with Intermittent Fasting

An RD's Experience with Intermittent Fasting // CarolynWilliamsRD.com

NOTE: The following content is simply to share details about my experience when fasting. It is not intended to promote or recommend the usage of fasting for any person or specific purpose. Each individual should decide what is right for them based on health, nutrient needs, lifestyle, and interest.


Even if it’s a fad or trend that has little scientific basis, I often like to try out different eating concepts—just to get a first-hand understanding of the effects to my body and lifestyle.  Sure, dietitians want clients to trust us because we only share science-based information, but I like to be able to share first-hand experience as well – good or bad.  So since I dug into the research on intermittent fasting, I decided to explore the hype behind bulletproof coffee and, well, after much persuasion, I made myself try intermittent fasting. 

Yes, I said “made” because even after going through the research on intermittent fasting, it was not a way of eating that appealed to me.  In fact, I didn’t even really care to try it.  One of the biggest things I worried about was how intermittent fasting would affect my blood sugar.  I am prone to low blood sugar and have had to apologize for my “hangry” behavior a few times. Bottomline is that I was 99.9% sure that fasting was not for me.  

How would it affect my energy, satiety, food prep, family dinners, and most importantly, my Friday nights at my favorite Mexican restaurant?  I opted to follow a 16:8 protocol, which essentially means I fast (or don’t eat anything above 35 calories) for a 16-hour block of time. I can then consume food within the remaining 8-hr period. 

Before starting the fasting regimen, I compiled a list of all my concerns leading up to my intermittent fasting trial.  Now after having tried it, I’m addressing each of those concerns based on my experience.


The 16-Hour Fasting Window

Could I even make it 16 hours without eating?  I am a person who doesn’t usually miss a meal or snack! Since I ended dinner the night before at 7pm, this meant that I needed to fast until at least 11am.  What I found was that I could make it and that it wasn’t hunger that I was fighting against but rather a mindset of “can I do this?”

Once I got into a routine of following the 16:8 pattern, I found that I really didn’t have much hunger and sometimes even had to remind myself to eat lunch.  I also found that what I ate the night before had a huge impact on how I felt the next morning.  Lots of carbs for dinner with little protein and fiber made me hungry the next day, and it was much harder to make it to 11:00am. However, when I loaded up on vegetables, lean protein, I was for the most part content.  


Potential for Bingeing

I’ve preached for years to not go too long without eating in order to make good food choices, so my assumption was that a 16-hour fast would make me more susceptible to overeating and would make me more likely to consume less healthy foods when I did reach my eating window.  To my surprise, I didn’t experience this, and I attributed this largely to my decreased appetite. I also really had no issues with low blood sugar – perhaps one of the biggest pluses - which actually still perplexes me.


Adequate Calories and Nutrients

People assume fasting is just another way to decrease calorie intake to lose weight, but the reality is that it’s not about cutting calories at all – just fitting them into a window of time.  So when done properly, you can meet required energy needs. It does take a little planning though, and there were several days when I was left with one hour in my eating window and I realized that I needed more food – yet wasn’t really hungry right then.  I analyzed several days of eating when I was fasting and intentional about meal planning, and I hit or was close to most recommendations. I was also pretty close to what my “normal” eating intake looks like. But when I didn’t have meals and snacks planned, my nutrient intake was pretty bad and calories lower than I’d advise as a dietitian.


Energy Level

I like to do early morning OrangeTheory workouts, so how would this work in the midst of fasting? And how would recovery be with not being able to refuel until 11am?  I wasn’t going to give up my workouts and didn’t have another chance to exercise in the day, so I was really prepared for hunger after my workout to be the ultimate fasting deal-breaker for me. But my body kind of rolled with it, and again, what I ate for dinner the night before made a huge difference. I also tried Bulletproof Coffee, which helps me quell any feelings of hunger. Energy during the day was the same as it had previously been or maybe even a little better.


Real-Life Perspective & Family Meals

While I’m getting ready for work, my kids are getting ready for school so we typically don’t ever eat breakfast all together – which worked out nicely for my fasting window.  I was able to eat the same foods as them for dinner, and we’re early-bird diners so this also worked well with my eating window. 

There was one night where I met a friend for dinner. Our reservations weren’t until 7:30pm which I’d probably wrap up eating about 9pm or a little before.  Per most 16:8 protocols, this means that I’d need to shift my eating window to 1 to 9pm which can be a little tricky for my lifestyle, as well as hard to do hunger-wise.  Ending eating at 9pm also meant that I needed to fast until 1pm the next day.


So what’s my verdict? 

I firmly believe that there are lots of definitions for “healthy” and that it can take many forms.  While I can’t say that I would recommend intermittent fasting across the board for everyone, I’m definitely intrigued by some of the positive side effects and interested to see what additional research suggests. 


Have you ever tried Intermittent Fasting? If so, what was your experience?

An RD's Experience with Intermittent Fasting // CarolynWilliamsRD.com