The Science Behind Intermittent Fasting (14 Studies) | Nutritional Science Explained

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Jeff Nippard : Ok a few quick things... Some of you may notice that I didn't include the one IF study on trained individuals in the video. I think Greg Nuckols did an excellent write up on the results and limitations but ultimately, it didn’t change the bottom line for me. I’d recommend giving his analysis a read here if you’re more interested in the LeanGains protocol or the effects of IF on trained folks: In short, it’s really likely that the fat loss benefit of IF comes down to a bigger caloric deficit. There may be improved health markers with IF, as implied from earlier studies, but they could be simply due to bodyfat reduction and we don’t know how they’d play out over the long term. There’s also some interesting new research on circadian rhythms that I just didn’t have enough time in this video to get into. Here's an interesting paper on that area: Finally, for those looking for a more practical guide, I’d recommend reading The Leangains Guide here: As always (of late anyway) I've included a full annotated list of references organized by order of appearance in the description box. Hope you enjoyed the video and I’ll see you guys again soon. Peace!

Rob Lipsett : Quality info and editing as always man. Easy watching!

GEEZY NYAMBE : I’ve never been this early to receive information from the lord of gains

Stephanie Buttermore : Editing getter better and better babe... HOT FIRE 🔥🔥🔥

RAGEfit : The best diet is the one to which you can adhere. Yesss 💯💯

Abby Pollock : Great vid Jeff 🙌 Ive been practicing IF for nearly 2 years now. Def agree with the appetite blunting effects with the caveat that there’s an adjustment period lol.

Islam Abuauf : The dedication of Dwight @ 1:22 Killing it with the Science explained series, Jeff! Would love to see more of "Bro Jeff" though 🐻

Samantha Grace : Lmfao i love your little Q&A part with the “bro version” of yourself 😂


Pinnacle Of Man TM : I aspire to edit like you one day man. Love to know what program & techniques you use (maybe in a vid) :-) FASTING is the BEES KNEES BTW!

William Chau : Who is your editor? Because honestly, aside from all of the useful information that can be gained from these videos ; the editing makes that much easier to consume all of this information. Edit : I just read the description ; Rashaun you are the man!

Skabumble : I think we need Broscience Jeff in every video from now on

Mike O'Tren : Do a live debate with Vegan Gains.

Seth Dunn : My views and experience with IF. Out of the gate, I am a firm believer in Overall Calories in your day is what matters most, not when you eat them. I started IF (LeanGains Protocol) in Aug. 2013, been doing it since for prolly 95% of the time. There are times when I may eat first thing in the morning. After having started on IF, my health markers did improve. I had a physical done Aug 2013, and my BP was almost at the point where the doctor was talking about putting me on meds. This rather pissed me off, since I am someone who I thought was pretty healthy. I tried to eat right, I worked out, I don't drink, don't smoke and do not do drugs. So of course that got a huge laugh out of my friends and family to hear the news. So I started reading a lot of material. Got my diet adjusted, and started IF. By December of 2013 I had another checkup and my BP had dropped down to I think 123 over 73.....then another checkup in Feb. or March of 2014 had my BP down to 113 over 70 and a heart rate of around 53bpm I was able to get very lean, my workouts in the gym were very good, I felt more focused in the gym as well as in the morning I am a fairly lean individual to begin with, doing IF definitely helped to get to the next level. Now as far as bulking with my body type....I will say IF I think does have drawbacks here. I just am not able to maintain an appetite long enough to get in the calories I need daily. I can go about 3-4 days with a huge appetite, then after that, it will just crash, so any amt of weight (water weight) I put on during that time, just gets burned off.... But overall I at my age, I am satisfied with IF and how it works for me and my body type. I can better see how what I eat affects how I respond.

Alan Lopez : You forgot to mention the "Godfather" of intermittent fasting, Brad Pilon. He was the first major proponent of IF with backed research in his book Eat Stop Eat. Later came Rusty Moore, Leangains, and Kinobody with a practical approach to IF. These guys were the first to create the craze.

Patrick Bateman : To me personally, still eating all day im struggling to eat above my tdee 😂

Zyzzus Christ : I hate midgets

Michael Bryant : 0:45 That’s not Martin Berkhan, that’s Andreaz Engström.

BosnishMaffia : Jeff, this editing is next level, keep it up dude!

Don Milliken : That's not Martin Berkhan in the video. It's Andreaz Engstrom, one of his clients.

Joespn : Another great one Jeff!👊

Alen GO : Why are you always just talking about anabolic signalling as opposed to health in general? As if having maximum anabolism aKa maximum muscle mass is the pinnacle of health. Guess what, 99% of people advocating fasting advocate it for HEALTH reasons (longevity, inflammation, gut health, lower blood glucose, REDUCED anabolic signaling, AMPK, decrease mTOR, IGF etc.), not gaining maximum amount of muscle mass. You're no better than Lyle McDonald and Alan Aragon...nothing matters and nothing is important EXCEPT DEM GAINS AND DEM MACROS BRAH. Ridiculous.

Faxnummer : Jeff! The video of the guy doing dumbell press is not Martin berkhan!!

marcos l : What if you run intermittent fasting while also counting your macros wouldn't that be best of both worlds?

Lucas Guimaraes : Ma boy Neanderthal fasted all day long and was A BEAST, even beat those Mammoths sometimes

Ketocarbs : Screw weight loss. Fasting is great for entering Autophagy.

Bieberhole69 : yes you hev very strong physic i wold love to see your haram

Quindarious Gooch : I'm surprised that you skipped over autophagy, which is a big part of why people take on fasting who have done their research.

HOTLILPAPI YT : Maaan I wanna just eat food I wanna live my life..

sillycod247 : When are you doing your debate with vegan gainz?

bryce e : *I tried it*  I was a huge skeptic of fasting.. until I tried it. Wow does it work.. I feel healthier and more alert, as well as leaner. Try it for a week to see if it is for you. You won't be disappointed.

Mohammed A : Me during Ramadan, great video Jeff 👌 still waiting for a full body training plan from you

David Hensel : I feel like so many people freak out about the thought of a 16 hour fast, but then forget that an 8 hour eating window would be breakfast at 9am, lunch at 1pm, and dinner at 5pm. Boom, you're intermittent fasting.

Chris : so you're saying 4x20 is more anabolic? suuuh dude

Malik Richardson : I was 242.5 lbs (40.8% BF) on 5/29/17, I just weighed myself and I'm 216 lbs!!! I was morbidly obese because I loved eating, now with the aid of intermitteed fasting my relationship with food has changed and I've been losing about a pound a week!

Jay McLaughlin : I’m a huge fan of intermittent fasting. I’ve tried all kinds of eating plans, but fasting is the only thing that’s given noticeable results in a way that is easily maintained. Having made fasting part of my lifestyle, I don’t actually follow any strict plan now. I eat 1-2 meals, late in the day. Workouts are typically first thing in the morning after a black coffee. I managed to lose around 16kg in 8 months and around 11% bodyfat whilst increasing strength. Like in your video, the weight loss has slowed more recently, but that will always happen as you get more lean. For me, fasting is easy and makes losing or even just maintaining my weight much more enjoyable. It’s also much better for fitting into my daily schedule

phillip harper : This is the only video I’ve squealed at like a little girl when i saw it on my feed! :D

Psun : HA if only you posted this yesterday! Spent a few hours going through literature for intermittent fasting yesterday!

Johannes Andersson : Manlets unite

Derick Moncado : You're editing and effects are so goddamn good. Shit.

thehiatusprt : Meanwhile, I’m on my 10th meal of the day with a protein ultra isolate ultra quick absorbing shake btw meals.

Bryan Pacheco : Intermittent fasting is simply a tool, not a diet. Skip breakfast and start your day of eating at about 12, 1, even 2. This will help you managing your calories when cutting.

Peter Traulsen : Hey Jeff, awesome video! Have you looked into the science about the HGH level increase due to intermittent fasting? According to a variety of studies the HGH level should increase as much as 800%. Please respond to this, as I'm working on a study concerning this. Thank you!

ervin B : Hey jeff, on a recent Joe organ experience, he had Chris Kessler (I think that’s his name, he’s a doctor) on, and he basically agreed with you that dietary colestoral doesn’t really affect your cholesterol, it’s right at the beginning of the podcast and there’s some interesting stuff.

TJ : Dude these videos are amazing. IMO your channel is by far the best at interpreting legit studies into simple terms we can all understand and relating to both normal people and the bodybuilding community. What would be interesting would be how this effects insulin sensitivity/response. Keep up the great work man you earned a lifelong follow!!

Cletus Kasady : I've been using IF for about a year to help with weight loss (57lb loss so far), along with a Ketogenic diet off and on. Both of these make it much easier for me to create a caloric deficit because they both lower my appetite. BUT be warned, if you say that to anyone on Keto or Fasting groups they will ban you for suggesting that calories matter.

Intelligent Investor : IF is just another tool in the bag to achieve my goals. Usually I just skip breakfast if I'm not hungry

Kelvin Lee : but if I'm a beginner who's been working out for a little over a year, is intermediate fasting recommended? Bcoz I'm curious whether if dong intermediate fasting will restrict my beginner gains.. tips pls~

Jonathan Feigert : I started intermittent fasting about 5 months ago. Can't say I've noticed any change in my ability to gain muscle or lose fat, but I definitely find that it blunts your appetite on the mornings and is overall more satisfying at the end of the day.

962RACER : thanks for the informative video, would be great if you look into the ketogenic diet, as it seems like a pretty legit method with a lot of scientific studies behind it. i'm curious as i've recently tried it for cutting and am noticing effective results, but still curious on your take on it.