Quick, if you told anyone that you were fasting to lose weight, they would probably think:
a) You’re crazy
or
b) You’re crazy
It’s sad, but anytime you tell someone that you’re fasting, the only acceptable reasons for doing so are for medical or religious reasons. If you even mention the words “weight loss” and “fasting” in the sentence, then you’re in for a world of hurt.
But in my opinion, fasting for the sake of weight loss isn’t crazy. Not at all.
In fact, strategically fasting everyday for 16 or even 24 hours can provide a whole host of benefits over the conventional “eat breakfast and 6 meals per day” saying.

Basics of intermittent fasting
So what exactly is intermittent fasting (IF)?
Simply put, IF is the act alternating periods of fasting (not eating) and eating. While there is no official IF program, most programs range from 12-24 hours of fasting.
So why is Intermittent Fasting awesome?
Well lets see:
- You get to eat bigger meals
- You get more work done since you’re not eating as often
- You have more energy since you’re not bogged down by food
- You get to stick your middle finger at every single fitness guru who says eating every 2-3 hours is absolutely necessary for good health
I could go on and on.
Is IF unsafe?
In short, IF is safe.
However, just like everything else in life, if you overdo it and take it to the extreme, then it will become dangerous. If an intermittent fasting program tells you to fast for 16 hours, you shouldn’t disregard that and decide to fast for 100 hours.
As long as you don’t do anything crazy like that, then there’s really nothing dangerous about IF.
But won’t fasting make me fat?
I never really saw the logic in this statement, but since when the hell did not eating make you fat?
But anyways, many people have this ludicrous belief that fasting will make them fat. This belief originates from mainstream media where they constantly promote the fallacy that fasting will force your body hold onto its body fat and make it burn muscle instead which is just incredibly stupid.
Will IF make me lose muscle mass?
When it comes to fasting, another popular myth that people believe is that fasting will make you lose all your hard earned muscle mass. This is simply not true and as long as you perform of heavy resistance training 2-3 times per week, then you shouldn’t fear about losing any muscle mass.
If you need further proof, check out this research study. In it, scientists showed that even when people ate a super low calorie diet (800 calories per day), they were able to maintain all their muscle by lifting weights. The reason behind this is because the act of lifting weights sends a signal to your brain that you want to preserve all your muscle mass.
But don’t you need to eat more often to have more energy?
This is exactly what food companies thrive off of. They create all these products that target people who need a “quick energy boost” or a quick afternoon “pick me up”.
But in reality, these people probably don’t even need these products. They buy them because they fear that they’re suddenly going to crash and burn when in reality nothing is really going to happen.
If you just give your body a chance to experience what it’s like be without food every 2-3 hours you’ll realize that you’ll actually have more energy than ever.
Just give it a shot.
IF is just another way to eat
Even though I love IF and would NEVER go back to eating 6 times per day again, I have to admit, it’s just another tool. It’s another tool to help you lose/maintain weight.
Unlike most fitness professionals, I’m not going to tell you that it’s 100% necessary to do something. I’m not going to tell you that it’s absolutely mandatory to do IF because honestly, it’s not for everyone.
Some people just love to eat small meals every 2-3 hours, and if you’re one of those people, then that’s cool. I’m not gonna judge you.
But if intermittent fasting sounds good to you, then check out the 3 most popular IF programs below.
A look at various IF programs
Over the past couple of years, more and more fasting programs have come into the market. IF is slowly growing in popularity, but here are the 3 most popular forms of IF:
1) Eat Stop Eat
Eat Stop Eat was created by Brad Pilon is now arguably the most well known form of intermittent fasting. I’ve been using this program for the past 3 years, and if you read my blog often then you know that I absolutely love this program.

Eat Stop Eat requires you to fast for 24 hours (e.g. 7pm on Sunday till 7pm on Monday) 1-2 times per week. On the other 5-6 days of the week, your main goal is to simply eat normal (maintenance calories).
The whole goal of fasting 1-2 times per week is to let those days create a calorie deficit of 10-15%.
Important Eat Stop Eat notes:
- Even though you’re fasting for an entire 24 hours, this doesn’t mean you get a free pass to the all you can eat buffet. The main goal is to simply eat normal after each fast. Don’t over or under compensate for anything.
- Despite fasting for 24 hours, you still get to eat every single day. So for example, if you start a fast on Wednesday night and end it on Thursday night, that means you get to eat a meal on Thursday night. Awesome, huh?
- Eat Stop Eat is more of a lifestyle change than an actual diet since you’re only eating less for 1-2 days of the week.
You can red my review of Eat Stop Eat here.
2) Leangains

And now we have Leangains created by the oh so famous Martin Berkhan (seen above).
But unlike Eat Stop Eat, Leangains has a much larger focus on pre/post workout nutrition and macronutrients.
With Leangains, you’re fasting every single day. Men will fast for 16 hours and women will fast for 14 hours.
While many people have effectively used Leangains to lose weight, many people have also used it to effectively pack on muscle mass. But not only is this muscle mass, it’s lean muscle, meaning minimal fat gains hence the term “Lean” gains. This is achieved though calorie and macronutrient cycling. If you’re ever looking for a program that lets you pack on muscle with minimal amounts of fat, then this one’s for you.
There are a couple different variations on Leangains, but all every one has you taking 10 grams BCAA before workouts.
I don’t want to delve into the rest of the details but if you’re interested in the rest of the Leangains protocol you can read the Leangains guide here.
3) Warrior Diet

And lastly, we have the Warrior Diet created by Ori Hofmekler.
This form of fasting to lose weight isn’t as popular as the first two, but it was the first form of IF I tried and till this day, I still use it from time to time.
The Warrior Diet has you fasting for 20-24 hours every single day, so it’s similar to Eat Stop Eat in terms of the fasting length.
During your fasts you can still drink water and zero calorie drinks like tea, coffee, and diet soda.
But the main difference here is that you’re eating all your calories in 1 massive meal per day. The mainstream media will probably never promote this way of eating, but hey, it works.
I’ve done it in the past, and you really don’t feel hungry while fasting. Plus, every day is like a mini feast since you get to eat a crap ton of calories in one sitting.
4) Honorable mentions
Some other great intermittent fasting programs include:
- Intermittent Feast By Nate Miyaki
- Fast 5
So which program is best?
Whew, all this fasting talk has gotten me a little hot. And hopefully I’ve gotten you a little bit excited too, maybe even got your nipples hard.
But if you had to choose, which of the above 3 is the best intermittent fasting program.
Well… I don’t know.
It’s really a personal preference. I’m not going say that Eat Stop Eat is the absolute best IF program out there because it’s not. It’s one of the best, but it’s not the absolute best.
Some people don’t like to fast for 24 hours and that’s fine. In that case, you should try something more along the lines of Leangains.
And if someone likes to come home from work every day and just stuff their face with food, then the Warrior Diet is probably best for them.
In the end it all comes down to choosing a program that fits your lifestyle.
Fasting to lose weight = not crazy
Seriously guys, fasting is not as crazy as you think. You’re simply waiting longer between meals.
But to be able to effectively use intermittent fasting, you need to have an open mind.
You need to be able to let everything that you thought you knew about nutrition and dieting behind and be able to step into this new world of “not eating”.
But trust me, once you starting fasting, you’ll never want to go back.
Have you ever tried fasting to lose weight? Did you like it? Let me know in the comments below.
Hi Keith,
I’m 5’8 at 195 pounds and was planning to fast 1 day a week. On training days (3 times a week, heavy weight), I plan on keeping my calorie intake at 1900 and on non-training days, 1700 calories. Does this seem realistic?
Thank you for all the useful information! By far one of my go-to blogs! I enjoy your no-bullshit approach. The strategic use of the word, ‘fuck’ really gets me, man. Haha!
Thanks man.
What are your goals right now? Fat loss? If so, 1900 is way too low for your weight. Use a 12x multiplier. You can go 100-200 above on training days but no more than that, and when you do, get the majority of the extra cals from carbs..
I am 5’3″ and weigh 120. I am a 43 year old female. I have always been able to eat healthy, walk regularly and maintain my weight at about 110. In the past year, I have gained 10 lbs. and none of my summer clothes fit. Rather than buy a new summer wardrobe, I am determined to lose the extra 10 lbs. If I completely fast all food for 2 days a week (about 1500 calories a day, as that is what I normally eat on a daily basis) and start lifting weights 2 or 3 days a week, do you think I can reasonably lose the extra 10 lbs.. in a month? Is there a better plan of action you suggest? Thank you for any input.
Probably not in a month give it at least 6-8 weeks. My best advice – be patient, you can’t rush long term, sustainable fat loss.
In order to kick-start things, I am going to attempt your suggestion this week of just 800 calories a day in one meal for 7 days and 3 days of weight training. Do you think this might help? Also, do you think changing my walking routine 3 times a week to running will help? Patience is not one of my virtues…..Thank you for your help.
Hi Kieth,
I’m a 17 year old senior in high school soon to enter Uni in the Fall. I’ve been a serious competitive swimmer for over 7 years. The college I’m going to does not have a swim team, and though I have been mildly recruited for other sports like track and field, I mostly want to focus on academics and drop competitive sports for a while at least. Athletics has been a huge part of my life and I’m terrified of the freshman 15. I’m currently 5′ 11′ and 145 lbs. I’m very muscular and lean ( I’m talking six pack and mildly vascular arms) but would like to lose a lot of my bulk muscle mass for a more feminine look (being a tall, muscular female is hard). I’ve only recently became interested in fasting, Any advice would be greatly appreciated.
If you really want to lose muscle mass on purpose, it’s as simple as not working out anymore.
There’s not much more to it.
“if you don’t use it, you lose it.”
Hi,
I apologize if this is a silly question, I’m looking to lose weight and I’ve calculated a weekly calorie goal..If I fast for most of the week and eat high amount of calories in 2 days (3k +) and the week still comes out to my calculated deficit, I’ll still lose weight?
yes technically you will, but that’s really not ideal. It just creates a really bad relationship with food.
Hi Keith,
Am female, 43 years old. I weigh 220 lbs. am trying to lose 20 lbs in a month. I just started fasting 5 days ago and I love it. I fast for 20 hours then have a four hour window to eat. Am keeping truck of my calories and eating 1200 calories six day a week and 2500 calories once a week. So far I have lost 5lbs. Can I eat anything I want or do I need to eat certain foods. I have also started lifting weights and walking, I can’t yet do high intensity cardio, any advice? I need to lose weight fast.
You’re eating too few calories, I would be getting at least 2000 at your current weight. No you still need to eat healthy foods, it’s not a “binge on candy&cookies” diet.
Thank you for quick response. Will eating 1200 hinder me in my weight loss? because am only eating one meal it’s quite a lot. True about candy which I hardly eat, I should have been more specific. I meant can I eat carbs and drink some wine/beer once in a while.
if it’s a lot, then eat more than 1 meal per day. Yes, if you eat too few cals for too long, you risk damaging your metabolism.
Hi Keith,
I’ve recently started IF (8 days in) and had a few questions. Currently, I use the LeanGains recommendation and fast for 14 hours. I end my fast in the morning between 7-9 and stop eating 10 hours from when I first have something caloric.
My first question is does it matter the time of day I fast or is the only important thing the span of time? I’m concerned that by eating within an hour or so of waking that I get less benefit than I would if I were awake and somewhat active for a few hours prior to eating.
My second question is what is considered breaking the fast and do I have to start the fasting time over if I break the fast? For example, if I stop eating at 4 and then have a light snack at 9 (150 cals or less) should I not eat again until 11 the next day? I know having an actual meal breaks the fast but am unsure how a light snack impacts the body’s response to fasting.
When is the best time to workout within the fasting window to get the best benefit from the workout or does it not matter? Is it better workout at the end of my fast and eat within an hour of working out or workout at the start of my fast and not eat for 10-12 hours after working out? Currently, I do resistance training 3x a week, cardio 2x a week, and take the weekends off if that’s relevant.
I’m sure I’m going to get a response of ‘it doesn’t matter’ to at least 1 of these questions but want to make sure I’m not doing anything foolish that can have a negative impact on my results.
timing doesn’t matter but most people end their fast in afternoon-night time
Breaking fasts aren’t that big of a deal as long as you hit your calories/macros for the day.
At the moment I am totally out of shape. Eventually there is a very special event coming up and I would really like to lose the pound quickly. So I am thinking of doing fasting (like I eat one day and then stop and then eat and then stop ) basically within a week I will be fast for 3 days. Would that be safe and would it help me to loose weigh
i don’t recommend fasting for 3 days in a row.
ohhh why is that ?
Thankyou for this article! Ive just started if 16/8 this week. Not really counting calories because I just wasnt sure what my calorie goal should be. Now that I’ve read a few of your articles, I would like your opinion please.
I am currently 180lb.
So not working out I would multiply that by 10. So 1800 is my calorie burn without exercise. Should I deduct 500 or 1000 from that? In my head I want to start walking 3 miles 3 days a week and kettlebell 2 days a week. No exercise on weekend and drink wine one night a weekend. I’m confused if I should change my calorie intake on exercise days or not and is 800-1000 calories a day seem right to you for 180 lbs 43 year old who would just love to be between 140 and 150 again? Thankyou for any advice your willing to give me.
no i wouldn’t minus an extra 500 from the 1800. I would just aim for about 1600-180 cals.
Hello Keith ,
I recently decided to fast for 7 days. I’m doing it to lose weight fast . I’m also taking vitamins to maintain my well being. But I’m 5’6 164 lbs & want to loose 14lbs fast I also do zumba 4 days a week but it’s hard for me to not eat I feel hungry every 3-4 hours . i never been the one to count my calories but if I have at least one meal a day do you think I will lose weight ?
Don’t try to lose weight “fast.”
It never ends well.
If you do 1 meal you still have to make sure you get enough calories along with your macros. Don’t eat so little that it starts to damage your metabolism.
Thanks for information, I really appreciate it. I was a slave to eating every 3 hours since 2002, I weight 205 and I’m 5’11”. I would guess im around 11-12% BF. I just started lean gains two days ago, and I’m loving it. My goal is to drop 3-4% BF, and to see the rest of my Abs. I want to know if I can still workout 6 days per week? I currently do 3 days of heavy lifting and 3 days of 25 minute incline treadmill walking, is that okay? My weight hasn’t changed in a couple years and I’m completely comfortable at this weight. I just want to lean out some more, because I hit a fat loss plateau. I have this stubborn fat on my back.
Yes, that sounds fine. Just don’t go too crazy on the cardio.
I’m 5″3 and 16 I’m fasting for 16 hours each day and consuming about 800 calories in a span of 8 hours is this healthy
I’m also 108 lbs
at your age i wouldn’t be tracking, just focus on eating healthy and mindfully.
I was doing the 5:2 and did really well on it, and then winter came and I gained all of it back and then some. I’m back on the fasting wagon and I’ve forgotten how light I used to feel! The fasting for 24 hours 1-2 days a week sounds doable.
Keeeeith, thanks for such an informative plus entertaining article, entertaining as I enjoy your sense of humor. I’ve got a quick question: If I fast for 11 hours, that also helps fat loss right?
I’ve fasted on my non-training days, however I have a major calorie deficit when I break fast. Is it really important to eat a certain amount of protein, carb, fat?
Thanks Keith
fasting helps create a big deficit. Yes macros matter, since they help influence body composiiton.
Hello,
I have a question for you. I am looking to begin a weight training program soon that will help me put on mass, but I wanted to lean down first. I am a 5’6 male and weigh about 126 lbs, but I am very “skinny-fat” (2-4 abs at most with the classic “pouch” on the bottom of my stomach).
To lean up, I have taken to the 16/8 intermittent fasting protocol and have kept my NET calories at 1600 or less (I have determined through calorie calculators that my sedentary daily requirements are almost 1800 so I eat between 1750-1800 a day and burn off 200-250 per day with a LISS activity such as brisk walking so that I don’t burn any of the little muscle I have at the same time). Do you possibly have any other suggestions to speed up the process?
if you’re skinny fat, i would just focus on putting on muscle.
I think I am anyway, but I have a very small waste (28.5 inches measured at the belly button). Regardless, I have always read that if you are “skinny-fat”, you are better off leaning down first before trying to build muscle since fat usually comes along with bulking and for people genetically prone to being skinny-fat, that bulk usually consists of more fat than muscle too (basically, I read that we got the worst of the worst genetics and will be in an uphill battle no matter what our goals are, be it skinny-ripped or bulking). Is this not true? If so, do you have any diet and calorie suggestions for me? As far as lifting, I am working with some very big guys who know a lot about building muscle, but I am having trouble locking down the nutrition aspect.
Thanks a lot for getting back to me!
no skinny fat people should really be focused on packing on muscle. When you really focus on lifting heavy and eating more you’ll naturally strip off fat and pack on muscle.
Nice summation in this blog! I tried for over a year to break the 180lb mark–hanging around 183-185 until I embraced the Warrior Diet (lifestyle)– and now am under 170 (168). I am 65 years old, but I run sprints and hills 2-3 times a week, do bodyweight exercises 2-3 times a week, and beat a tire with a sledgehammer and box. All that just to keep up with my wife! Oh, we also hike 1-2 times a week averaging 5-10 miles per hike.
While I did all that– only by adding IF to my regimen was I able to scale off those last 10-12 lbs– and eventually I’d like to get to 160 hard and lean.
I never have like eating breakfast–and I workout during my lunch break–so the WD is perfect for my lifetsyle.
Nice job, Dave.