Actually, you should follow the money about all medical research (about all science research, in fact).
So, for example, if a ketchup-producing company has backed a study that concludes that tomatoes loaded with sugar are good for you, consider that a “meh” finding.
Actually, I would consider that a “Feh” finding, which is one step up in an ignore-this-conclusion hierarchy.
But such studies are, alas, rampant in medicine, particularly nutrition studies.
So, according to findings on studies in top nutrition journals in 2018 which was published today in the journal PLOS ONE, roughly one in eight such nutrition studies had “involvement from the food industry”.
And no surprise “studies with industry involvement were more likely to report results favorable to industry interests.”
That doesn’t mean, of course, that the findings are wrong.
They may be quite right, but you’d really want confirmation from non-biased sources before accepting those findings at face value.
And no, ketchup is not an acceptable veggie substitute.