Keeping SEO benefit of an old URL by changing content

[jgodwin]

We have a blog written in Oct 2012 that accounts for 30-40% of our traffic (174K pageviews per year/80% bounce rate). We are considering updating the content but are concerned that it will fall off the search engine's map if the content is updated to include information that is not exactly the same, but relevant. The URL would be the same and the original blog content would be shortened with a link to the full blog. The new content would include other FDA products under investigation. Here is the blog: http://myadvocates.com/blog/fda-issues-warning-about-so-called-brain-supplement-prevagen

[AlanMosley]

There is a risk, but if the content is relevant its a small one. you could rank better also.

[evolvingSEO]

When you say "the original blog content would be shortened with a link to the full blog" can you explain that a little bit more? You mean an article like this http://myadvocates.com/blog/fda-issues-warning-about-so-called-brain-supplement-prevagen would be only partial and it would link to the full version somewhere else? And the destination new content is what would contain more FDA products?

Also, it is likely you are getting most of your traffic from only a handful of posts. I would do an 80/20 analysis of your blog content (how I show step by step here) or just eyeball your analytics. To mitigate most of your risk you could leave the top 5-10 posts for traffic the same.

As Cyrus points out here you should be careful with how much you change the contents of the page. Google is good at understanding semantics, which means they are more likely to decide not to pass value through redirects because of changes if those changes are too different than the original content. They also understand document structure, so if you're changing from a full post to another format you should be careful with that too.

[EcommerceSite]

Keep what you have, but add an update paragraph at the end, this should limit your risk.

[RyanPurkey]

Google is very good with semantically relevant information and updating posts like this with new results and further information often also provides a fresh content boost. With the volume you're talking about, I'd recommend rolling out the new content in phases so that you can see how it impacts results and decide best for your situation. Cheers!