In my humble opinion (I don't run in this niche) the best way to do this, is be WH and build an email list... then you can go grey hat / black hat to your email list.
Give away something useful and relevant to nutra like - the top 10 shittiest products currently on sale by scam nutra companies.....
Get them on your e-mail list, give them the ebook or e-mail with the 10 shittiest products and explain why they're shitty.
Next e-mail, tell them about the top 3 products that actually work.
Next email, tell them the amazing results 1 client had after they took 2 of those products and combined them together.
Next email offer them BONUSES worth over $200 if they decide to try any of the 3 products you've recommended them.
Next email offer them $1000 worth of BONUSES if they order, but they must order in the next 24 hours.
Then go back to providing value... telling them about other shit in the nutra space.
etc.
etc.
But... point is... build a list... then do your BH shit on your list away from FB.