Supplements on FB, for those who run it, you prefer CPC or CPM?
Kinda odd that easiest part for my company was to get unlimited amount of good accounts, but getting cheap clicks its not that easy.
So you prefer CPM or CPC when it comes to that vertical?
Hey there!
This will mostly depend on your goals and your audience. Normally CPM is more expensive.
The best thing to choose is to go to your FB ads manager, select the targeting and see the reach + price you'll pay. Check different options, and decide based on that.
For example, if you run in tier-1 countries, targeting people with interests "organic food" and "supplements", CPC appears as a better strategy. So it really depends 
Getting cheap traffic isn't relevant to choosing cpm or cpc. Good targeting + good ads are key. Me personally always choose CPC, but both have their pro's and con's.
Cpc optimized for conversion
As stickupkkd mentioned, the cost is more likely to do with your advert creative. If your just ripping stuff and expecting it to work, then it’s never going to get those fresh cheap clicks