Why 16:8? what about 12:12?

(Dan Sayo) #1

I have started intermittent fasting this week. My question is why I need to fast for at least 16 hours, and why not just 12?

Thanks in advance to your advice,

(Karen Parrott) #2

Last July I entered a study out of the Salk Institute in La Jolla, CA. I baselined at 12:12. The study had me over the next 12 weeks shorten my feeding window and I wound up doing 17:7 for my ending feeding window.

The study encouraged us to eat our food earlier in the day and fast on the afternoon and the evening times. I was able to lose an unintended weight gain of about 8 to 10 pounds close to my goal weight. Previously I was 70 pounds overweight and having an extra 8 to 10 around my goal weight wasn’t my idea of a good time. All that work and I was developing a huge muffin top over my skinny jeans Nooooooo!!!

So anyway that’s why I shortened up my window. I am now experimenting with some alternate days of 17:7 and some alternate days of 12:12.

Before this I was obese or overweight from age 6 to 46. I’m now age 51 and 3 to 4 years and menopause. Having any sort of tool like this that is free for me to experiment with is gold

Hope this gives you a sense of how I used different timing windows to my advantage. My body is certainly rewarding me with the lowest weight body wise and the most muscle in my whole adult life. Probably better sleep too.

One last thing is I can eat a little bit higher in my carbs if I eat them earlier in the day, all from vegetables. The fasting helps me stay Keto.

(Carey) #3

12 hours is good, really good, certainly better than 4 hours!
The point of extending the fast to 12 and beyond is that the longer the fast, the longer amount of time you avoid raising insulin in the body. There is no magical number with 16, it is just a longer amount of time that your pancreas gets to rest, your cells get to enjoy the persistence of low insulin, thus giving them an opportunity to heal from insulin resistance…

(David K) #4

I think 12 hours is closer to a typical eating cycle. Eat Dinner at 6pm, eat breakfast at 6am.

(Ketopia Court Jester) #5

It seems to me that a lot of IT proponents encourage people to put off eating as long as possible in the morning as the easiest way to extend their fasting period and I thought I was a failure because I just couldn’t make that work.

For me, it’s the opposite. If I wait too long to eat in the mornings, I get anxious and shaky. I can ignore hunger later in the day, but putting off breakfast just fucks with my keto zen. Just pass me the bacon and shut up.

(Carpe salata!) #6

I’ve been doing 20/4 on weekdays - so easy to not take lunch :smiley:

Then on weekend eat up to the point of where I’m just over food. Ready for the next week.

Oh and one announcement: I smashed the 100 with a 99.9kg this morning. Woohoo.

Trim the sails me hearties we’re headin south!

(Carpe salata!) #7

That’s me in the food court with just the 600ml of spring water not interested in food and messaging keto forums.

(sora namor) #8

Because its at 16h that the true benefits start higher testosterone, GH and more, i tried 44 hours a few times… i feel at least for me 12h is not enough.

(Dan Sayo) #9

Thank you all for your replies, really appreciated! I was just wondering if there was a research paper on intermittent fasting recommending the 16:8 over the 12:12 with medical data.

(Dan Sayo) #10

I appreciate if you can share me some links on those facts, thanks

(sora namor) #11


Lots of info on this too


(sora namor) #12


(sora namor) #13

You need to experiment, everyone is different the most popular fasting method is the leangains method 16 fasted 8 hour window to eat. From what i have research and read people have had the best results using this method, also i train at the end of my fasting period, so yes all my training is done fasted, i have never notice any lack of energy, i feel great afterward, i usually wait an hour, shower relax and have my biggest meal of the day, right now its keto so chicken, or beef, with cheese, veggies etc nothing fancy and fat gravy. I eat 2-3 times per day, and 1 of those meals is usually a whey protein shake almond milk unsweetened and olive oil.

This is what works best for me so far.

(sora namor) #14

I do not think there is any research so far all that i have read are for animal studies. This is why you need to experiment, most people follow the lean gains plan 16/8 you can read Brad Pilon eat stop eat its a good read other then that i have not seen anything on research on say pubmed mayo clinic, but Brad explans the fasted hours for GH Testosterone, lower IGF1, etc, and its around the 16-18h mark.

(Dan Sayo) #15

thanks, reading through the 44-hour-diet link you gave looks like thats a 2-day continuous fast, not the answer I was looking for on my 16:8 question

(sora namor) #16

Dan i am just posting various links of what i have read, i also bough some books etc. But yes the 44h is very extreme and most people will never have to do this. Its just to show you the variation on fasting.

In Brad Pilon book Eat stop Eat he does stat the most benefits start at the 16-18h mark, but Brad says to fast once or twice per week for 24h…


(sora namor) #17

This would be it http://www.precisionnutrition.com/intermittent-fasting/chapter-7

ist a study experimentation i really like that one, he was not keto but he did intermittent fasting 16/8

(Dan Sayo) #18

Thanks, i will continue with the self-experiment, as I also have a baseline to compare my blood work when I last had my checkup July.

(sora namor) #19

Yes like i said Dan we are all different and you need to see what works for you, note some people are unable to fast, my ex girlfriend needed to eat in the morning or she had huge headaches, i have met a few people who need to eat or they have all those awful side effects.

Granted i am able to fast 44h this might look like close to impossible but believe me its a lot easier when you get pass the 24h mark you are just not hungry.

I am still experimenting myself just did my macros and realize i was eating way too much even if my carb intake is around 30g net per day.

Lots of twerking but i do believe the end results will be quit worth it.


My plan exactly.