Is It the Seed Oil, the Fries, or Harder Than Hubris Suggests?
Making America Healthy is an industry with very low barriers to entry. Lots of people have fun with it. They also make lots of noise. The trouble is that because of those low barriers to entry, most of them, including some academics, do very little to actually make Americans healthy. Instead, they generate headlines and confusion. Are potatoes bad for us generally, or only when they’re fries, or only when they’re fried in seed oil?
The current state of potato punditry is enough to make our heads spin.
Mixed Messages
Some of this nonsense comes from our clownish secretary of Health and Human Services, Robert F. Kennedy Jr. He says it’s the seed oil that’s the problem. It’s “poisoning” us. Not the fries. If fries are made with beef fat, he’ll promote them.
On the other hand, the Harvard School of Public Health has been telling us for some time (as recently as last year) that potatoes are simply not a healthy vegetable choice.
But now, they’re leaning on a new observational study by one of their post docs to say that potatoes are A-OK. So long as you don’t fry them. Then the old advice stands. They’re bad.
Leaping from Associations to Policy
In the New York Times, we find sane perspective from professor Emily Oster. She says the problem is not so much the potatoes or even the frying oil. The real problem is pundits and policymakers jumping on observational studies that show us nothing more than an association. It can lead to some serious policy mistakes:
“Relying on bad evidence can lead to significant mistakes. Correlational evidence about the health risks of butter led people to substitute margarine instead; at the time, this contained trans fats, which turned out to be more concerning than butter for heart health. Mr. Kennedy has promoted replacing seed oils with tallow, nevermind that the saturated fat in tallow is probably worse for one’s health. Worse, the current panic over seed oils has led some parents to worry about seed oil use in infant formula. These oils are necessary for the formula to mimic the nutrient composition of breast milk, but there are now parents seeking to make their own formula to avoid them.”
Making good nutrition policy is harder than hubris would have us believe. Pursuing policy that relies on observational associations inevitable leads us to mistakes.
Click here for free access to Oster’s perspective in the Times, here and here for reporting on the latest potato punditry from Harvard. For the study that prompted this, click here.
Pommes Frites med Chili, photograph by cyclonebill, licensed under CC BY-SA 2.0
Subscribe by email to follow the accumulating evidence and observations that shape our view of health, obesity, and policy.
August 8, 2025
