You can't just make a massive claim like that about such a common ingredient without backing it up. I'm not saying it's not true, it could be, but it's just inappropriate to state something is true like that with 0 evidence aside from personal experience.

If that were the case posting on forums like this would be either entirely inappropriate or a complete waste of time.

You complainers are missing the mark. You obviously can make extraordinary claims (see above for evidence).

What isn't reasonable is to also expect large numbers of people to take them seriously without evidence (see above for evidence of people questioning unsupported claims).

Maybe a better way to phrase our question is "is making such claims productive?"

See my above comment - it's a relatively well studied topic, and yes - there is a link.