Nutritional science is a pretty volatile field. Worse yet, the general public is especially slow to catch-on with the current consensus. With antioxidants, for example, it's been known they're a double-edged sword for at least a decade. Excessive antioxidants could really be bad for you, yet "antioxidant" is a top-tier buzzword in any health store.
More than volatile, it's complex. And complexity doesn't trend.
There are all sorts of trace elements that do all sorts of things for our bodies. However, our bodies are well-adapted to doing all sorts of things to compensate for a lack of trace elements. So what we're left with is near-optimal function on suboptimal nutrition… but optimal nutrition leads to superior function. Thing is, "optimal nutrition" is individual, contentious, and subject to constant revision due to experimentation and study.
But what it boils down to is:
NEWS: "You aren't getting enough nutrition."
CONSUMER: "Shit. I need some nutrition."
NEWS SPONSOR: "Mutherfucker we got nutrition pills like Snoop Dogg got chronic. Love your hair, by the way. But not so much as I would if you bought some of this dope-ass shampoo!"
CONSUMER: "Dope."
NEWS: "Nutrition pills are shit."
CONSUMER: "Fuck! I coulda sworn y'all sold me these things…"
NEWS SPONSOR: "We were young then and naive. But we've learned. It's all about nutrition FOOD. Have some yogurt with a bacteria with a made-up name in it! How 'bout some breakfast cereal with more iron than a ball peen hammer? No, holy fuck - how 'bout some VITAMIN WATER? And a Lexus?"
CONSUMER: "You take credit?"