Nearly as often as I hear questions about how to make someone's backside look better, I get asked to weigh in on whether "intermittent fasting" is a good choice for them. On the basis of what this diet actually is compared to how people are using it; the answer 90+% of the time is a resounding NO. Let's dig into this industry trend, and show why jumping to this dietary strategy is not something you as a beginner should worry about just yet.
Understanding Intermittent Fasting
Intermittent Fasting (IF) refers to a kind of dieting that varies the amount of calories one eats from MORE THAN NORMAL to at least 25% LESS THAN NORMAL on fasting days or weeks.
The typical purpose of fasting is to stimulate your metabolism, detoxification, etc during fasting phases. It does this by burning "reserve" fats for energy as an acute response to unexpected decreases in your intake. The problem with "IF" is just that...there are a lot of "IF's" to consider. People are drawn to these diets because (IF done correctly) the body is stimulated to clear fat/toxins out of the body through increased sweat and bowel movements (IF you are getting enough water and fiber). The fasting response assumes that you have been eating enough for your normal metabolism, but IF you haven't preceded it with a SURPLUS of calories, it won't work.
As you can see, that's a lot of "IF's" to keep track of when looking at intermittent fasting. People come to believe that they are gaining undesired fat or feeling bogged down because they "eat too much", then someone along the way convinced them that fasting was a surefire fix...and to them I reiterate, "there are a lot of 'IF's' to consider" first.
The Parts You SHOULD Be Addressing
Most people wrongfully make habits of skipping breakfast, eating very little through day, and then binging dinner at the end of the day. So the fasting effect that you would be shooting for with an IF diet would not even be triggered. Instead, you should calculate how much you should be eating through the day and the protocol for "how" you should be eating (from our last article). You can't trigger fat burn if you've been overriding it for prolonged periods of time, so your first steps should be undoing the damage by hitting your calorie/timing/macro goals.
Where Do Diets Like Fasting Fit In?
Reviewing the priority pyramid we introduced in the last article, you'll see how eating breakfast and hitting your calorie/macro needs should be the base of your dietary considerations. After that, the nutrient timing section refers to the "protocols" reviewed in our last article. Our macros series detailed how to adjust your macros based on your body type and goal, for once you are getting enough calories and are following the correct protocols. THEN we actually consider specific diets after everything else has been normalized. Have you taken those steps already? Then you probably won't see any benefit from "dieting" in any way.
The ONE Group Intermittent Fasting Works For
The popularity of difficult diets (like this and ketogenic diets) make them sound easy to accomplish for the results they tout...but this just is not the case. Realistically, every specific diet has a benefit that typically comes at a great cost to achieve. In the case of intermittent fasting, you have to have an astute knowledge of how your body responds to different levels of nutrition relative to your burned calories. Don't know what that means? Then it probably isn't you. The group that would know this is who we see on stage for upper level bodybuilding competitions. At this level, the athletes have generally been overfeeding through a "bulking phase" and begin an alternating caloric intake during their "cutting phase" right before competition.
Bodybuilders in Prep
*Note - if you aren't in a competition cutting phase and under the supervision of a credentialed nutrition coach...then "intermittent fasting" isn't for you
This is because they are going into a short-term caloric deficit to burn fat right under the skin quickly for stage, but can't maintain low intakes due to high exercise volumes. So on the days they exercise, their intakes are higher than what they are used to. When they have light or off days, their intake is lower than their need. Sound complicated? Well, that's because IT IS and isn't a generalized dietary protocol for nutritional newcomers. Even these athletes only employ the technique for a couple weeks under supervision, so there's no need for an average person to feel inclined to take on this diet. For a healthy person, that hasn't been under eating, and that burns roughly the same amount of calories every day; there is no marked difference in the results from intermittent fasting compared to just decreasing calories overall for a short time. The following graphic displays the meta-analysis of fasting studies showing this relationship:
Don't waste time researching how to make your "fasting" routine best for your situation, because chances are your body won't respond right to it anyway. The amount of effort it would take you to successfully implement "IF" would be much better spent understanding how your body actually works. So set your dietary priorities as they should be:
Follow the right Nutrient Timing Protocol (based on your goal), and
Tweak your macros appropriately (based on your body type and goal).
Specialized dietary protocols may be something a trained coach takes you through temporarily, but they usually aren't beneficial to attempt on your own. IF you are already tracking, and IF you are eating a surplus for your needs, and IF your meal timing protocols are on point; then you wouldn't be asking about intermittent fasting. Because if you are not competing to be the next Arnold Classic champion, then "IF" probably isn't something you should be concerning yourself with in the first place.
I hope this article shed some light on this hot topic, showing you that there are much more important things to be looking at in your nutrition than unnecessarily dieting. Upcoming articles will continue to dig into the nutritional aspects that actually DO matter, so keep your eyes peeled for what's coming!