This means a lower ranking. And your site will be harder to find in the searches. You may get rewarded for that. As with the previous suggestion, use the keywords within your document instead. Using keywords that have no relevance to your subject.
Some people load there keyword list with anything they can think of.
For example, say it's an olympics year. Lots of people are searching for olympic related sites. So, you put a lot of olympic keywords in your tags, even though your site has nothing to do with the olympics. Don't do this. Keep your keywords relevant.