A common reaction to intermittent fasting is straight-up FEAR. Fear that you will die. Fear you are doing something harmful to your body. Fear it will be difficult. Fear of the unknown. Let’s tackle these haunting specters one by one, shall we? But first: here’s something to ponder which stuck with me ever since I heard it awhile ago as a throwaway “did you know?” fact. After researching it, apparently it’s legit: the average person has enough stored energy (in the form of body fat) to fuel walking over 1000 miles. Needless to say, you’ll be just fine if you skip a meal.
Onto the questions.
Will I Die?
No.
Won’t Fasting Make Me Lethargic?
Nope. You’ll actually be alert and energetic! Fasting saturates the body with energy by ramping up lipolysis, the breakdown of stored fats into potential energy. It literally shifts the body into an energy-producing mode! The longer you fast, the more fatty acids are produced. Fasting can even release up to 200-300% MORE fatty acids into the bloodstream from fat stores than needed (ultimately unneeded fatty acids are simply restored or used elsewhere in the body).
Won’t I Be Miserably HUNGRY When Fasting?
Nope. You actually will likely have zero appetite when fasting. Zilch. You know that feeling when you lose your appetite because you’re excited about something, or in love/like/lust? It’s kind of like that. Fuel is not limited in the fasted state, since the body utilizes fat stores when fasting, as discussed above. You won’t be hungry because you’ll be filled with fuel from within! (And not in a vague esoteric sense – like in an actual sense). Your body will tell you it doesn’t need to eat by killing appetite, even if your “mind” protests otherwise.
Intermittent Fasting is like when I went on the Great Horror Campout. I was scared, but then it was fun and awesome! Click the pic for more on that!
Won’t My Metabolism Slow Down? What About Starvation Mode?
Ahh yes: the Metabolism and Starvation Mode. We fear it. It haunts us. We MUST eat a certain amount of calories consistently, otherwise our body will assume we’re starving and we won’t lose ANY weight.
For starters, the metabolism “slows down” in response to calorie restriction, not time restriction. If you undergo calorie restriction for a substantial period of time (which is not the basic form of intermittent fasting), the metabolic rate will lower to compensate. That being said, it will not “shut off” completely or enter some irrevocable mode where fat burning ceases all together. Fat loss will simply just occur at a slower rate. And even then, it’s not a permanent nor even problematic situation.
And that’s calorie restriction. As for intermittent fasting, since the metabolic rate does not decrease in response to time intervals between meals as long as adequate nutrients are consumed for the day, you will not enter some nefarious “starvation mode” when fasting. Your metabolism will not slow down. In fact, some studies even show that short-term fasting increases metabolic rate (go figure). Skipping a meal will surely not put you into starvation mode, nor will going 24 hours without a meal! I do it all the time, and my metabolism is just dandy!
As one medical journal eloquently notes, “studies using whole-body calorimetry and doubly-labelled water to assess total 24 h energy expenditure find no difference between nibbling and gorging.” I just like how they said that. In other words, eating consistently throughout the day is no different than a fasting pattern when it comes to the metabolism (“energy expenditure”).
Will I Lose Muscle From Fasting?
Fasting actually spares lean muscle tissue by mobilizing fat and ketones as alternative substrates to protein. As a 2012 medical journal review notes about fasting:  “Lipolysis, lipid oxidation, ketone body synthesis, tailored endogenous glucose production and uptake, and decreased glucose oxidation serve to protect against excessive erosion of protein mass.” Furthermore, fasting promotes autophagy, which is actually required to maintain muscle mass. If you feel paranoid, you can always supplement with amino acids during the fast.
Will I Overeat In My Feeding Window?Â
The short answer is: highly unlikely. The slightly longer answer is: highly unlikely, but even if you did, it probably wouldn’t matter that much anyway. Studies find fasting decreases appetite and does not instigate compensatory overeating. On the contrary, people are more likely to under-eat in total when practicing fasting. And even if you do “overeat” per se, fasting encourages enhanced nutrient partitioning, so food is much more likely to be used for fuel and repair rather than fat storage. Studies show that mice who overeat after fasting do not gain weight like mice who overeat in a non-fasted pattern. And if you couple intermittent fasting with the extremely satiating Paleo diet, overconsumption of food during your “feasting” is extremely unlikely.
Will I Automatically Store Everything As Fat After Fasting?
Quite the opposite. As discussed above, after a fast has ended, the body experiences increased nutrient partitioning, and is less likely to store food as fat, even in excess. When fat storage does occur after fasting, it is also more likely to happen in other areas, such as muscles, than before. Furthermore, studies show that eating after a fast increases total fat oxidation from the meal in comparison to eating in a “normal” meal pattern.
I took this photo in the catacombs underneath Paris. Now THAT’s a scary place. Click the pic for more on that!
Won’t Intermittent Fasting be HARD?
Nope. It’s almost laughably easy.
See Why Intermittent Fasting is a Breeze for more on that!
References
1. http://www.ncbi.nlm.nih.gov/pubmed/10837292
2. http://ajcn.nutrition.org/content/86/1/7.full
3. http://ajcn.nutrition.org/content/60/1/29.full.pdf+html
4.http://classic.ajpendo.physiology.org/content/303/12/E1397.full
5. http://bja.oxfordjournals.org/content/85/1/69.long
6.http://classic.ajpendo.physiology.org/content/303/12/E1397.full
7. http://www.ncbi.nlm.nih.gov/pubmed/19945408
8. http://www.ncbi.nlm.nih.gov/pubmed/20104028
9. http://www.biomedcentral.com/content/pdf/1475-2891-9-35.pdf
10. http://www.ncbi.nlm.nih.gov/pubmed/9155494
11. http://jama.jamanetwork.com/article.aspx?articleid=1108368
12. http://www.cell.com/cell-metabolism/abstract/S1550-4131(12)00189-1
13. http://classic.ajpendo.physiology.org/content/303/12/E1397.full
