BMR and fasting. Help me understand

(Alex Dipego) #15

Isn’t he saying more that you need to supplement __ protein to save protein on your body not so much your metabolism?

Studies show metabolism speeds up to near the 60hr mark in fasting. Not eating is better than eating small amounts.

(G. Andrew Duthie) #16

I think that advice is most applicable for those with a good deal of weight to lose, and hence, sufficient body fat to sustain daily energy requirements. But as with many such things, the advice has become somewhat generalized, but may not serve everyone equally well.

#17

Not really, @beckyjoy. There is good reason why fast and feast is not like yo-yo dieting.

Let’s first be clear what is yo-yo dieting. To me, it’s like someone who turns down calories, because of CICO mentality. So, the body, searches for what mechanisms it can turn off, to save on calorie expenditure. For example, let’s say you wanted to save money on your monthly utilities bill. So, you turn off all lights you don’t need, unplug appliances, turn down heat or air conditioning, wash clothes in cold water, etc. this is why people with lowered metabolisms feel cold all the time. I’ve screwed up my metabolisms after years and years of following bad advice (low calorie dieting). So, for someone who is yo-yo dieting, when the food comes back in at higher calories, the body still maintains lowered metabolism and starts storing fat (“just in case the low calorie yo-yo happens again”).

When fasting, something else is happening. The digestive system is “mothballed”. Everything is shut down and put on a care and maintenance program. Just like someone going on a very long vacation, shutting every process down in the home (no one turns on lights, or use dishwasher, or use vacuum, or use clothes washer. The heat and air conditioning is shut down, and no water being used). The amount of energy to run a moth balled house is almost nothing, so the body does not go in a panic state…there is plenty of energy on board to do care and maintenance of a digestive system that takes almost no effort to keep alive. So, the body does not turn down your metabolism. In fact, it patiently awaits when food comes back,…and when it does, it’s “all hands of deck”… Or maybe the pun “all glands on deck” :joy: to rev up the digestive system.

Our bodies have evolved from a feast or famine (fasting) way of eating. The body recognizes this as a normal way of survival. Today, we have freezers and refrigerators to store food. In ancient past, you killed an animal, you ate it, and then you don’t eat until you kill the next one. There is no refrigerator. Same with fruits…when the strawberries are out, great, eat strawberries for two weeks, and then they are gone until next year (for only two weeks in season).

This is why yo-yo is completely different from feast-fast.

(Becky Searls) #18

This all makes sense…but then if you are adding fat due to low bf…the fast isn’t “pure” anymore (not that I care in theory…but where is the line between a fat fast that’s benefitting your metabolism and calorie reduction that’s slowing it down?)

(John) #19

I wonder how long the effects last, this makes it sound like just from having high blood sugar you have lower metabolism.

(Todd Allen) #20

Another consideration is your BMR dropping due to deficiencies leading to impaired functioning or is it due to improving metabolic efficiency? During an extended low calorie spell of typical low calorie dieting, without a lot of care one is likely to become deficient in a wide range of vitamins and minerals. Fasting, at least in moderation, promotes recycling and deficiencies are less of an issue.

But regardless of how it is achieved reducing fat mass lowers the amount of metabolically active tissue which all else being equal lowers the amount of calories needed to sustain BMR. One can counter this by increasing lean tissue mass. And some believe reducing BMR by enhancing metabolic efficiency is a good thing that reduces oxidative stress and slows aging.

Why Am I Getting Cold When I Have So Much Body Fat?
(Alex Dipego) #21

The goal should be to strengthen your metabolism. At my leanest 8% at 165lbs I was eating 3600 calories regularly. It took me a year getting my metabolism there. Adapting takes time and fasting shouldn’t slow your metabolism. Under feeding will. Going with The warrior fast let’s say is a 20:4 fast that promotes berries and veggies throughout the day under 500cals then a huge meal before bed.

Metabolic health is based on regular fuel and if you’re so lean that you think you’ll under eat then you may need to not fast. Or just fast and be okay losing some protein from the body and enjoy the health benefits. Fasting isn’t impossible when lean, it just hard.

(Alex Dipego) #22

Your metabolism adapts to its input and what kind of input. You eat a lot of calories you’re metabolism (if healthy) will increase. If you under eat your body adapts to it. Glucose in the blood isn’t the problem. It’s insulin the the blood. Keto life has high levels of glucagon which increases sugar in the blood so your body doesn’t crash (with a healthy pancreas). Glucagon presence increased the presence of things like HGH, neo/epinephrine which have metabolic boosting properties by increasing your cortisol levels which in this case is something you want as it sends fat burning signals.

(Crow T. Robot) #23

Interesting! What was it when you started and did you mainly get there through IF or were there other factors?

(John) #24

So it sounds like something like an alternating day fast, with high calories on feast days would be optimal correct. Eat more, metabolism goes up, or at least doesn’t go down, fast which does all sorts of things including prevent your metabolism from dropping.

(Alex Dipego) #25

I started at 2200. I ate 2 times a day until I could manage a single meal at high calories. I then took my week total, so let’s say I ate 15000cals that week, I’d bump it to 15100-15300 depending on my weight change. If I dropped 1.5-3lbs I’d add 250-300 cals extra a week. If it was <1.5 than I’d add a 100 or so. Realize what I’m doing though. Spread 100-300 calories over 7 days it’s nothing. It’s almost irrelevant, which was the point. I was adding such a minuscule amount that my body found it easier to adapt to.

(Alex Dipego) #26

Really it is using fasting to fit your lifestyle without thinking you have to not eat. If you are lean you probably should be eating a lot of food, but I say this due to activity level. You don’t have to be super active but naturally humans store fat to survive long hours without food and to travel long distances. We’re amazing at it. If you wish for super leaness you have to hack around a bit because it’s not optimal to be super lean. You may want to look 5% BF but the body probably wants 12%. I felt shitty at 8% BF but I wasn’t keto adapted and my fuel was all messed up. It felt like I was fighting myself. Now I’m at 12% and I’m happy I feel great but I know I need to play around to trick myself leaner but I want to do it without the huge negatives.

(Mike W.) #27

Also feasting then fasting helps your body get used to burning more fuel during your fast.

#28

Brilliant!

#29

If I drive up my metabolism on feasting days, won’t that prevent any drop in BMR during fasting? According to @richard ''s calculator, I would have to eat 120 calories in fat during fasting (my BMR is about 1200) to prevent a drop. Megan Ramos suggests feasting prior to fasting to drive up metabolism to get the most benefit from fasting. And the science shows that metabolism increases during fasting. So I shouldn’t have to eat fat during fasting if I feast first, right?

(G. Andrew Duthie) #30

Sorry, but I just don’t know the answer to that, though I suspect it partly depends on the length of the fast.

I’ve certainly heard plenty of folks share n=1 success stories with feasting and fasting cycles, though.

(VLC.MD) #31

I wonder how many “calories”/energy is “saved” by not having much digestive work to do (fasting)? It might not be very much at all.

#32

@Abrane I wanted to follow up with you on this strategy. I’ve been applying it for the last several weeks and I’ve gone from a maintenance level of calories of about 1400 a day to 1610 a day. I can’t believe it’s working! I plan to keep this up until I’m in the 2000 calorie range. For a 55-year-old female, 5’2" and 121 lbs, I would be so pleased if I could comfortably eat 2000 calories of glorious meat and fat per day. The last couple of days, however, I’ve noticed a drop in my appetite. Did you experience periods of lower appetite when you were steadily increasing your maintenance calories?

#33

What a fascinating thread, so glad I took a look!
And, according to the calculator @richard I only need to eat about 2 teaspoons of coconut oil/day to stay in the fasted state? I could do that!

#34

I am so excited to hear that this is working for you, since I am a 51 yo woman who would also love to eat so many calories of meat and fat! (Of course, you are also on maintenance and I am not there yet.)
What was the calorie increase each week, 70 it appears, which really does seem minuscule. However, over time, this has led to another few strips of bacon or some slices of rib eye…I like this trend.
I hope you’ll keep the experiment updated, I am really curious to see how this goes. Best wishes for that upgrade! :wink: