The 15mg/d they used in that study is just the standard dietary intake (top end, europeans). Looked a number of other studies that also used just regular intake levels as "supplementation". Weird how they all stay small when the no observable adverse effects level is much higher.

>(3) Results: Compared with a placebo, spermidine supplementation significantly increased spermine levels in the plasma, but it did not affect spermidine or putrescine levels. No effect on salivary polyamine concentrations was observed.

Which might be fine if the metabolite is actually the responsible molecule.

Helpful reminder that mice lie, monkeys exaggerate, and ferrets are not people (surprisingly enough).

Order? Considering the source of Spermidine, might be easier to get it for free from your local glory hole

Given the concentration, you'd have to drink half a litre of human seminal plasma to match one 15mg supplement pill.

I have no idea what the concentration of seminal plasma is in semen, but even if the latter was pure plasma that's still 135 sessions to equal one pill.

It's possible that others routes of administration have better absorption than oral.

Wheat germ is another source of spermadine and you can buy it at most supermarkets. Sprinkle over cereal

It contains Phytic Acid. Might be the reason humans started removing it from wheat. It gets broken down in sour dough too.

https://en.wikipedia.org/wiki/Phytic_acid?wprov=sfla1

[edit] remove doubled word

What’s wrong with phytic acid? I read the link you included. The only negative seems to be it might not be digestible, unless I missed something else?

It irreversible binds minerals and they get excreted i.e. you can't make use of them.

It inhibits the absorption of iron, zinc, and calcium

Does the spermadine also get broken down in sour dough, or is whole wheat sour dough a potential good source?