(Please upvote if you find it interesting, this is am important question for me)
Thank you for sharing it! Is there any scientific evidence to support the answer to this question?
What of the following types of fasting should one do if he or she is not interested in weight loss (but rather muscle gain), but is very interested in all other health benefits fasting might provide and specifically in the benefit below (related to glomerulosclerosis) as this one can be life-saving(!)?
1. Intermittent fasting daily
1.1 No food food for 16 hours a day
1.2 No protein and no carbs for 16 hours a day, but some fat for breakfast
2. Alternate day fasting
2.1 No calories on a given day - one day a week
2.2 No calories on a given day - two days a week
2.3 No calories on a given day - every other day --- this seems to be the method of the discussed rat study (below)
2.4 Limited calories on a given day (max 800) - one day a week
2.5 Limited calories on a given day (max 800) - two days a week
2.6 Limited calories on a given day (max 800) - every other day
"Many strains of laboratory rats develop spontaneous progressive kidney failure with development of proteinuria and glomerulosclerosis. Rats fed on alternate days showed preserved kidney function as demonstrated by preserved glomerular filtration rate and renal plasma flow, compared to rats fed ad libitum."
Gehrig JJ, Ross J, Jamison RL. Effect of long-term, alternate day feeding on renal function in aging conscious rats. Kidney international. 1988;34(5):620-630.
Is there anything else to keep read and keep in mind?
If you are unsure, what expert should I consider asking?
Thank you again!
Here is a couple of answers:
1. About the reasons why it might not be generally necessary to cut 100% of calories instead of 50% (but it's in general, not relating to this specific study I am referring to, and it's focused on weight loss)
2. The actual source of study and a ton of useful information
Excellent topic! You saved me making one about fasting myself.
I've tried lots of different ways of IF, most of what you have listed above, at the moment i've settled on one meal per day, it's usually with a starter and maybe one snack during the day if i feel hunger. I don't necessarily think this is the best way of doing it, i even have my doubts, but i simply don't enjoy eating during the day and really enjoy a big meal at the end of the day.
If you don't want to lose weight then intermittent fasting a few times per week is probably the best way to maintain what muscle you already have and get some benefits of fasting, but but what if losing a significant portion of that muscle and rebuilding it would build a better body? I find the longer i fast (i've only gone upto 5 days) the easier it is to gain lean mass when i resume eating, not sure how far i can take that! I haven't figured it out but i'm certain there is a way of fasting, exercising, and eating that can build strong muscle pretty reliably just by reading your own body, which a prolonged fast can provide some clarity on, but perhaps we could also measure biomarkers to know the optimal times to self-eat and eat non-self :)
To me true fasting is intermittent, not a daily routine, historically it would've been due to unsuccessful hunting, or intentionally for healing or spiritual reasons. The latter two would've mostly been intermittent bouts of not eating anything for prolonged periods beyond a few meals, but all of them intermittent. If you do it routinely then it's not really intermittent as we adapt to consistent routine. Intermittent means 'irregular, not continuous or steady'. Doing a 18/6 or 20/4 you still get some of the benefits, i do it myself, i'm practically doing 22/2! Still, in my experience the real benefits of fasting come when you are pushing your limits beyond a few meals.
There's many good articles on fasting yet nowhere near enough research, there was a study that showed that hunger pangs during fasting are associated with neurogenesis and i think at least a couple showing that fasting stimulates neurogenesis. I can testify that when i push through each slight feeling of hunger or energy dip and go deeper into a fast, i feel sharper & sharper, and intuitively feel it benefiting my entire being, whatever that consists of.
My favourite stuff to read on fasting is by Herbet M Shelton as he supervised so many fasts himself.
If you are curious, there are some good answers in comments here http://suppversity.blogspot.com/2014/04/alternate-day-fasting-well-researched.html
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