Should I fast 14-16 hours, even if I'm ravenous?

[floramaria]

Let's not forget that Stephen Cunnane thinks we only need about .5 to feed our brains. In that case 3.3 is a pretty hefty dose of ketones! Just thought it good to keep these numbers in perspective for the forum as a whole.

Cunnane's recommendation is for healthy, young E4 carriers to address the inherent reduction in cerebral glucose utilization that we exhibit as early as age 30. Extrapolating from that; those who are older, menopausal, PCOS+, IR, or experiencing symptoms of cognitive decline, may need higher amounts. In several recent interviews, I've seen Dr. Bredesen recommend BHB levels as high as 4.0 mmol/L.

I am still waiting for my ketone meter, which won't be shipped til late September. My plan was to aim for low level (ie .5 ), so I am finding this a bit discouraging since I am both older and post menopausal! I don't have any problem extending fast to 14-16 hours, and do not feel particularly hungry, and certainly not ravenous. Generally feel fine fasting though I occasionally experience energy drop around 16 hrs. When my energy drops, I eat and full vitality returns.
For those of you who have a lot of experience with ketosis, your input would be extremely valuable. Is there some value in lowest levels of ketosis? Is there some other marker besides the ketone levels, glucose levels, and mental clarity that you use to gauge whether you a getting benefit? For past 10 years have had SCI . I'd appreciate hearing what levels you try to achieve and maintain. ApoE4,3. thanks.

[TheBrain]

First a comment as an aside for the benefit of newer readers new to ketogenic diets (if any are reading this thread): You mention being in "mild ketosis" at 3.3. I have thought .5 - 1.5 or 2 or something is mild. Someone can go to 5 or 6, maybe especially if they have epilepsy or brain cancer or are doing extreme fasting/exercise such as our rockstar George does. But I think these should be considered outliers rather than the standard next to which 3.3 would be considered mild. Let's not forget that Stephen Cunnane thinks we only need about .5 to feed our brains. In that case 3.3 is a pretty hefty dose of ketones! Just thought it good to keep these numbers in perspective for the forum as a whole. Maybe this should be its own thread.

I know that Julie already addressed the matter of what mild ketosis means, but I just wanted to add that in The End of Alzheimer's, Dr. Bredesen says on p. 180: "Aim for about 0.5 mM to 4 mM betahydroxybutyrate." He does use the term "mild ketosis" on the preceding page, so I'm assuming this is his range for mild ketosis. However, what Julie wrote about Dr. Cunnane's recommendation makes a lot of sense to me. If I had edited Dr. Bredesen's book (having worked as a technical editor for 13 years; oh my, what a pleasure that would have been!), I probably would have requested clarification on what he considered the range to be for mild ketosis and when someone should aim higher versus lower.

That comment dovetails with another observation with all the talk about extreme fasting ... namely that we begin to easily suggest a standard that may be completely unnecessary for many to achieve an excellent healthspan and lifespan and that could make lots of readers feel unaccomplished when they undershoot it. Therein lies your good question about how necessary the long fast and very-low animal protein intake are for you. I'm with listen to your body.

Thanks for this advice. Given what you and Susan have suggested, I think I'm going to listen to my body on a day-to-day basis. If one day, I feel great and not particularly hungry, I'll aim for 14 hours; but if I start feeling too hungry, I'll just go ahead and eat. If on another day, I wake up ravenous, I'll just make sure I make it to 12 hours. Every day is different.

I also have the issue of not getting enough calories in during a smaller eating window. My stomach feels full quickly. If I push it I get reflux, so I eat to comfort and then whatever I got in is not going to carry me 16 or more hours every day (although occasionally I easily go 15 hours for whatever reason, and I always welcome and enjoy these days). My practice is to fast in the morning until I've felt good and hungry for a while, but not ravenous or where I can't accomplish anything because my brain is offline. I don't see the point of being ravenous when I know I can't make up the calories and then sleep through the next night without hunger.

If I go past a certain point of fullness, I'll get reflux as well. It will interfere with sleep, perhaps for hours. It's just not worth it. And if losing concentration is your signal to eat, I'd say you're doing your body good by listening to that. An offline brain isn't particularly helpful.

I'm wondering if you don't notice cognitive benefits because you've been generating ketones a long time. I remember when you first started testing and were surprised to find you were already generating ketones. Maybe you're just used to their cognitive benefit?

The cognitive benefits I've experienced came before I went into ketosis, as I implemented the Muses Labs protocol. I would like to see more cognitive benefits. My ability to sustain attention is a significant issue, as is mental fatigue. And my memory for details is definitely not what it used to be.

Dr. Gundry said my IGF-1 was perfectly good at 118 ng/mL (<130, while the lab reference range was 60-217) and that was while eating more than his prescribed 20 gms animal protein/day, probably more around 60-90 gm but I wasn't counting. It's not what I consider high protein, but not very low either, being his 20 gm target everyone talks about. He said if I wanted to push it lower and be in the centenarian camp, I could do so by eating less animal protein. Being a centenarian isn't high on my list though. I'll be thrilled to advance my healthspan from whatever baseline I'm at at any given time.

Could you possibly elaborate on the connection between IGF-1 and protein intake? A year ago, my IGF-1 came in at 46 ng/mL. I asked my endocrinologist at the time what that meant. She said it was because my fasting insulin was so low (due to being in mild ketosis). She wasn't concerned about it. Here's the reference range from my results, but this make it appear I'm in my 70s (though I'm 57).

IGF-1 Reference Range.png

[TheBrain]

Alysson, I think the key to your question might lie in your comment about HPA axis dysfunction. I'm not ravenous in the morning, just hungry.

If you are ravenous in the morning, perhaps it is related to the release of cortisol to bump your blood sugar, which normally occurs but might be dysregulated for you, having HPA axis problems. Have you recently done any cortisol testing? Do you test your blood sugar at all? Might be interesting to see where these are when you wake up and then as you go without eating.

With known HPA dysfunction, I'd personally be reluctant to stretch the time you don't eat, because you might be stressing the HPA axis even farther. Perhaps at this point, go with 12 hour fasting - you will be getting good autophagy at 12 hours - and talk with your doctor to work more on the HPA problems.

Susan, this is what I reported in my initial post in this thread:

In recent testing, I found that my ketones and FBG remained about the same shortly after waking and right before I ate breakfast. I was ravenous and waiting for the 14 hours of fasting to pass before eating. So:

8 a.m.: Ketones 3.3; FBG 72
9:30 a.m.: Ketones 3.1; FBG 73 (14 hours of fasting)

So even though I was ravenous, my blood glucose was holding steady. In the past, I have noticed at times a spike in my morning glucose by waiting and not eating. I should probably do more testing to see if my pattern is to hold steady as I wait to eat. I recall reading that Mercola recommends testing blood sugar every 30 minutes before eating in the morning. When it starts to spike, eat. If I tested every 30 minutes every day, all my finger tips would be black and blue!

Last year, I did cortisol testing through the DUTCH hormone urine test. My cortisol was scraping the bottom of the sloping range. At the time of testing, my doctor had me taking phosphatidylserine, 100 mg per day. He had me stop, saying that this supplement was dropping my cortisol too low. I haven't had my cortisol retested since.

[SusanJ]

Well, I think you've mapped out a smart strategy. Aim for 12 and go longer if you can. Today I was busy working on some stuff and didn't eat my first meal until 1:00, but other days, I'm happy with 13. Always smart to listen to your body.