Nope, not ironic.

But if your aim is to increase people's health, you're going to do a better job using accurate information.

The initial studies showing anti-oxidants have health benefits have struggled to be replicated, and new studies have shown anti-oxidants may be having negative health impact.

Edit: since a couple of people have asked, here's one fairly good source, there are others if you search. http://www.ncbi.nlm.nih.gov/pubmed/22419320

I see this as the perfect example why the article is mostly wrong. It supposes a personal motivation for "ignoring" allegedly good advice, whereas I'd bet that a lot more readers are looking at things from a objective, scientific angle where just anecdotes don't really count ("every person I tried this on" ain't that much better than "it works for me!").

Probably some variation/inversion of Hanlon's Razor.

Not everyone who wants to see more evidence for every claim and trick is doing that out of sheer denial. There might be some room for the Nirvana fallacy here ("SuperMegaFoodStuff didn't make me into an Adonis in a week, so it's crap"), but in general I'm pro-skepticism.

I'd suggest you to review the current science literature on this subject as it so far it's starting to look bad for proponents of the "You need more vitamins"-campaign.

Antioxidants Could Spur Tumors by Acting on Cancer Gene http://www.sciencemag.org/content/343/6170/477.summary

Supplement Alert: Antioxidants May Protect Cancer Cells Instead Of Protecting Us From Them http://www.forbes.com/sites/daviddisalvo/2014/02/08/suppleme...

Why would he be ironic? Consuming too many antioxidants have been tested and turn out to have some pretty ugly negative effects, just like too much of anything else at all.