Listen pal. Keyword density of content or header doesn't matters anymore. Google has stop worrying about it long ago. Unless your content or header looks like its automated or look like its been used just to stuff keywords, everything is good.

2-3% keyword density is normal for a post as far as the anchor text are different from each other and pointing to various links. You should always take care of the proper placement of keywords at the right paragraph.

I think KD is an over-rated concept. Even with similar keyword densities one page may rank while another does not. And that's true even if they have the same link profile. That in and of itself should show the (lack of) value of KD.
To explain how that concept works, consider a page that uses the exact same keywords at the start of the page title, at the start of their h1 tag, and in all their inbound anchor text. It may get filtered for being too closely aligned with the target keyword. Now imagine that the same page is redone, shifting word order is some spots, shifting singular to plural in some spots. Now the same page may not get filtered even if it has the same or similar KD.
KD also has two toxic side effects. Some people write what ends up sounding like robotic copy. Others, in an attempt to increase KD, end up editing out important keyword modifiers and semantically related phrases, which not only lowers their traffic (since they took many relevant words off the page), but also makes their page look less like other top ranked pages.

Thanks for your valuable opinion.

thanks for your valuable opinion.

Advantageous judgement!! Thanks for sharing :-)

It you focus on the reader benefit and enjoyment of reading the article you shouldn't need to worry keyword density. If your word-choice affects the quality of the writing then that is something which to be concerned.

Write naturally.