Try rereading and thinking about what you write before clicking 'add comment'. You've posted a number of things that are not very accurate in terms of the facts.
Maybe your comment on vitamins[1] was considered to be inaccurate because it referred to vitamins in general rather than certain vitamin supplement products. The vitamins present in food seem to be absorbed well by the body in most cases. (I wasn't the one who downvoted you, so I'm just guessing.)
Also, citing a reference to back up your statements when you make them can never hurt.
Edit: On second reading, it also seems that your statement about vitamins was unrelated to the parent comment, which talked about dependence on increasing doses of amphetamines. As far as I know, vitamins don't have this effect.
Your comments on 'getting rich' seem to reflect a lack of knowledge on the subject. Nothing wrong with that offhand - we're all here to learn - but you might post with a bit less certainty.
Also, try writing correctly - not everyone here does, but it seems relatively common. I don't mean if you happen to make English mistakes, but proper capitalization and that kind of thing make for more pleasant reading.
My current average of comment point is 2.11. That means that in average I get only 1 upvote for each comment. The other posters here have a similar average.
There are not free upvotes, or an upvotes faucet here. Try to write meaningful comments, preferably in an area where you are an expert. Try to avoid oneliner and jokes, because most of the times they are downvoted.
Yes, I made one snarky comment and got a number of downvotes. I guess I don't have a common sense of humor.
The best way I've found to get upvotes (for comments) is to either:
1. be the first or second commenter and say something insightful or unique
2. reply to the first or second commenter and say something insightful or unique.
In my experience, comments further down the page, or later replies to the OP, just don't get viewed as much.
But one of the other comments makes a good point. Why do you care? Do employers care about HN scores? Is there a secret club you get into at a certain point? Or is it just about wanting to understand the HN culture better?
You get them by contributing meaningfully to discussions. I've been on this site for a while and gotten lots of upvotes, but ultimately it does not matter: what matters is learning, sharing what you know, and meeting people.
