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What is the first thing you think about when you hear intermittent fasting (IF)?
If you said, "Being hungry" you are not alone. Like the girl in the picture, the idea of purposefully going without eating seems like a pretty horrible way to spend your day. But what if I said you already do this? If you stopped eating last night around 7 PM and didn't eat breakfast until 7 AM, you fasted for 12 hours and probably didn't think twice about it. The truth is, we all do this to some degree and that is where the confusion starts. How much or how little fasting is the correct amount? With different diets and programs suggesting everything from 8-hour to 24-hour fasts, it is a tough subject to nail down. So today we are going to talk all about IF, show how it can be helpful if used correctly, and most importantly, explain why you wouldn't want to do intermittent fasting before you have a sound nutrition foundation established.
What are the benefits of Intermittent Fasting?
According to Mercola.com and several other websites, IF can lead to:
- Increased insulin and leptin sensitivity
- Reduced risk for chronic disease
- Ability to burn more stored fat
- Decreased triglyceride levels
- Decreased inflammation
- Weight loss
We did some digging and these benefits seem to hold up in the scientific community with several studies showing positive results in both mice and humans. However, what most websites and diet plans using IF seem to gloss over is that you should already have a healthy diet before trying IF. That leads us to the second question:
Who should Try intermittent fasting and when?
We believe nutrition is a lifestyle choice that takes time to develop. We wrote a three part series about creating your own personalized nutrition plan (read it here) and we placed everyone in one of three tiers: The nutrition newcomer (Focus), the nutrition explorer (Personalization), and the nutrition specialist (Performance Optimization). We believe any sound nutrition plan needs a solid foundation and that is built upon eating real foods, avoiding processed foods, and limiting added sugar.
Only after months of a client or athlete demonstrating their ability to live this way do we suggest they start looking to tweak their plan to make it more personalized. It would not make sense for us to suggest IF in the Focus tier. Instead of our clients focusing on the quality of their calories, they will spend time and energy thinking about when to eat those calories and how much they can feast on before they have to stop eating again. The focus is in the wrong place and this can cause a host of problems such as yo-yo dieting, being hungry, increased stress levels, and simply being angry with the idea.
Instead, we would possibly introduce intermittent fasting in Tier 3: Performance Optimization. At this point, our clients have already demonstrated a sound understanding of basic nutrition and are putting their knowledge to good use every day. Beyond just counting macros and calories, those that are working towards optimization already have a healthy body fat percentage and are looking for ways to make small improvements, not global changes like those in the Focus tier. So for the well-established nutrition specialist, we would recommend tinkering with IF to see if it makes their life better or worse. The important part to remember though is these clients are already eating very healthy so that will not change simply because they eat at a different time of day.
How do you start intermittent fasting?
Assuming you already have a sound nutrition lifestyle in place, you should start off with small changes and then wait to see what happens. For example, if you already don't eat between 7 PM and 7 AM, we would suggest trying to wait until 8 AM to eat breakfast or not eating past 6 PM at night. If after a week or two of trying this new pattern out, you report increased energy levels or simply feeling better, we might recommend trying to stretch that intermittent fasting to 10 AM and so on.
It is completely plausible that someone can feel extremely healthy and maintain lean body mass by not eating between 7 PM and 11 AM, which would leave an8-hour window each day to consume the proper nutrients.
Some go beyond these levels and fast for 24 hours several times a week. The former football player, Hershal Walker, famously only eats dinner each day and has been doing so since he was 16 years old. Now at 53 he still looks like he could start for the Cowboys. It works for him. However, I had a captain in the fire department that essentially did the same thing as a means of losing weight. He lost a lot of weight and then just as quickly put it all back on and much more. There were no nutrition foundation, healthy eating habits, or sound diet, and IF actually caused him a lot of harm in the long run.
The truth is intermittent fasting can absolutely lead to superior results. It just won't matter much if you don't first build that foundation. If you are thinking about trying IF, we recommend reading our three part series on how to build an amazingly effective nutrition plan (Part 1). If you feel that you are already in control of your nutrition, don't eat any processed foods, avoid fast foods, limit your added sugar intake, addressed issues like sleep and stress levels, have tried adjusting your macro-nutrient intake, and have been doing all of this for quite some time, only then would we recommend trying intermittent fasting.
Until that point, you are focusing on the wrong big picture and could cause yourself more harm than good.