As a nutrition coach, I like to say I am “diet agnostic”, meaning I don’t subscribe to one particular dieting approach as long as it maintains basic fundamentals of good nutrition. I have had clients ask about intermittent fasting (IF), so I decided to find out more information about it and do an experiment. Why not?
In simplest terms, IF means sometimes you eat, and sometimes you don’t. While some people will fast for 24 hours at a time, most people have both eating and fasting windows in one day. Some popular combinations are 14:10 (fasting 14 hours and eating 10 hours), 16:8, or 20:4. The time schedule is a personal preference, and the times aren’t limited to these combinations.
Why would someone do IF? Recent research shows that, when done properly, it might help:
Regulate blood glucose
Control blood lipids such as cholesterol
Reduce the risk of heart disease, cancer, and other diseases
Manage body weight
With these benefits looking pretty sweet, I decided to give it a try but on an experimental basis. I run 5-6 mornings a week but never in a fasted state. How was that going to work with my body? I decided to start with testing a fasted run and see how my body felt.
During my first week, I found that running fasted wasn’t a problem for me, at least for my shorter weekday runs. I decided ahead of time that my longer Saturday run would NOT be in a fasted state since I usually needed to fuel during most of those runs anyway. I wasn’t willing to risk blowing up on my run for ANY eating plan!
After about 6 weeks, I started losing energy. I was exhausted ALL. THE. TIME. I had to start taking daily naps just to function. I knew I needed to track my macros but didn’t have enough energy for that simple task; however, my experience already told me the answer...I wasn’t hitting my protein and numbers. Lack of protein always leads to fatigue for me. I was determined to continue one more week to see if I could get over the hump, but I just couldn’t do it. One morning, I decided to eat breakfast and see how I felt. The difference was instantaneous. My energy
skyrocketed that day with no naps required! I decided at that point my experiment was over.
What did I learn?
To listen to my body. I have always been one to eat on a schedule, but now I am better at noticing if I am actually hungry. This is huge for me! I am now working toward only eating when I’m hungry.
To wait for real hunger cues. Now, I am trying to wait a while after those first hunger pangs to see if they go away before running to the kitchen.
Feedback, not failure. Full-time IF didn’t work for me, and that’s okay. I gained information I can share with others.
What important points do I hope others can learn?
Most people use IF as a weight loss tool, even if it may have other benefits. A smaller eating window means fewer calories for most people, which will eventually lead to weight loss.
IF works for some but not all. We are all different, so why should we all react the same to IF?
IF is not a free pass to ignore basic nutrition. An eating window is not an invitation to eat anything and everything. A continued focus on whole foods, reduced sugar, hydration, reduced processed foods, and lots of protein should still be maintained.
Research has also shown that a little can go a long way. Precision Nutrition found that a day of fasting had more benefits than fasting for multiple days a week. Moving forward, I am still going to have some IF days here or there. Honestly, it works well for my schedule at times. Like many things in life...it doesn’t have to be all or nothing.