Friday, September 25, 2020

so, i've been struggling with this banana peel smoothie all night. am i doing this or not?

i'm not "leaving the peel on". and, i'm not doing it to reduce waste, either - up until last week, i put my banana peels in the freezer and tossed them into the woods every few weeks, to let them decompose naturally, thereby keeping them out of the landfill and helping to clean the fucking car exhaust out of this absolutely filthy city.

what i'm trying very explicitly to do is recover usable vitamins, and very specifically recover vitamin e, which i'm coming up short on by keeping my total fat intake down. consuming e requires consuming types of fat that i don't want to consume. so, how do you get the e without all the dangerous fat? banana peels are one way, potentially. 

i need to address this crazy claim that banana peels have vitamin b12, though, because it comes up in every search on the topic. b12 is widely understood to only come from animal sources. it's not a protein, and you can't get it from beans. you can get it in places like soy milk, but only because it's added.

i hate reddit, but this is useful:

so, it seems like there's just one source, and it's some nutritionist from san diego. this woman was wrong. that said, she's so wrong that i suspect she was probably misquoted. she probably meant to say b2, and appears to have been wrong even there, but there's at least b2 in the more commonly-seen-as-edible part of the fruit. the internet seems to make all sorts of claims about the peels that are true about the fruit, or true about species of banana that we don't actually eat. for example, there are red bananas, and they have lots of carotenoids, but that doesn't help those of us eating the yellow varieties all that much; it's kind of like how red peppers have 100% of the beta-carotene you need, and yellow peppers have basically 0%.

so, essentially everything you see about banana peels in a basic google search appears to be complete bullshit.

i also want to address this absolutely stupid remark:

"Go ahead and google 'monkey eating a banana,' and you'll see that even most monkeys are peeling the banana before eating it. If monkeys are smart enough to figure this out, we should be, too."

that seems to be a widely shared view.

well, go ahead and google "monkey eating it's own shit" while you're at it.


them monkeys sure are smart, huh?

it's perfectly plausible that monkeys and humans are both too fucking stupid to realize the nutritional value of banana peels. it's hardly intuitive, and just watch a buckley's commercial to realize the correlation between taste and nutrition.


so, instead of citing the wisdom of monkeys, why don't we try to do some fucking science and figure this out? 

with all of the claims floating around about what is in the peels, and an apparently high level of confusion regarding what is in the peel vs what is in the fruit (that is, people seeming to speciously assume that if it's in the fruit, it must be in the peel, too), and even claims to defer to simian intelligence on the matter, a perusal through this analysis of what is actually in the peel is perhaps of some use:


that is, unfortunately, the best source i can find about the peels, directly. however, this is an extract, and i'm wary about relying on it for data.

so, there would not appear to be any b12, any a, or any c in the extract. it does seem to have a few antioxidants, some phytates and an exceedingly high amount of vitamin e. 

but, note that vitamin c is water soluble, and you might expect it to get destroyed in an extraction process of that sort, along with anything else that is water soluble. what do you really get if you calculate that?

let's take a step back, first. 

i have now made the smoothie and must admit it doesn't taste great, but i don't care. it's s not awful - it's better than buckleys - but its because i overpowered it with chocolate soy. it doesn't taste dissimilar to orange pekoe tea, really. first, how did i make it?

when i made my daily fruit bowls starting last week, i washed the peels and chopped them. i then put the cleaned and chopped peels into a tupperware container, and put that container in the freezer waiting for it to pile up. note that studies demonstrate that e can freeze for short periods with minimal loss, but with that kind of concentration, i may even want a little loss. i initially hoped that each container would house a week's worth of peels, which was 7. then, i doubled my banana consumption, bringing it up to 14 peels/week. then, i realized i could only really fit closer to six peels in a container. and, now i'm realizing that i can only really fit four in the blender - meaning i should only be putting two day's worth of bananas in the smoothies and should be packaging them in fours. so, this should be an every other day thing, rather than a once a week thing.

so, if i'm throwing four peels into a smoothie every other day, and each peel is about 20 g, that's about 80 g total. let's work with that.

well, .43*80 = 35 g which is a potentially toxic amount. and, it can hardly be actually right. rather, it would seem as though the extract has 40% vitamin e, after it's stripped away everything water soluble, meaning it's one of the few things that survived the process of extraction. you may consequently want to be careful with banana peel extracts, as they would appear to have dangerous concentrations of vitamin e.

what other information can i find?

this study measures the amount in the stems and the flowers. why not the peels, then? i don't know:

it produces an average of roughly 0.15 mg/100g. so, for 80 g, .80*.15 = .12 mg. that's an average of 1% of the rdi - if the peels are roughly similar to the stems and flowers. 

are those two results consistent? i don't know.....it seems like a big gulf....

note that, if those numbers are close to applicable to the peel, i'm also getting the following from those four peels:

1) about 8% rdi for C
2) 10-12% rdi for thiamin (b1)
3) ~6% rdi for riboflavin (b2)
4) ~40% of rdi for b3 <------is that what the nutritionist meant?
5) ~5% rdi for b5
6) ~14% rdi for b6

if that's right, it doesn't seem worth it for the e.

is it worth it for the b3, though? it might be. i'd like to think i can figure something else out.

and, try as i may, i cannot find better data than this.

so, what is more useful? is it the data about the peel extract? or the data about the stems and flowers?

more to the point, i'm finding it difficult to finish it - not because of the taste, but because of what i presume is a high carb concentration. i drank about half of it, and i'm full. this suggests to me that if i'm doing it to get at some e to keep fats and sugars down, it's misguided, anyways - this seems like a fattening meal, according to my gut reaction. and, while my gut is not a spectroscopic lab, it's pretty good at judging how many calories i just consumed.

does it make sense to think these things have some e? well, kiwi skins have a lot of e. there's e in broccoli leaves, in the entire pepper plant, in kale - it seems like the right idea, really.

but, i can't prove it in a way i'd like to. 

so, i'm going to hope i can find a better idea....

if you can get me some clearer info on this, please contact me.