Hey, you, the dude reading this story on your phone over a pile of french fries: Back slowly away from the crispy spuds. They're out to get you.
That's the apparent takeaway of a study published this month by the American Journal of Clinical Nutrition. It analysed the potato consumption of 4440 American participants, aged 45 to 79, over an eight-year period. Researchers used questionnaires to determine each person's spud-eating habits, including both fried and unfried products, and then used the data to trace links between potato consumption and mortality.
"No study existed about this possible association!" emailed Nicola Veronese, a scientist with the National Research Council in Padova, Italy. Veronese was the lead author and one of a dozen researchers who took part in the study. "There were some studies, re: potato consumption and cardiovascular disease and mortality, but we did not find any paper re: potatoes and mortality!"
Exactly 236 people died during the course of the study. After adjusting for a variety of factors - education, race, income, alcohol consumption and exercise, among other things - the researchers concluded that people who eat french fries more than twice a week are doomed. Doomed!
Okay, they didn't actually say that. What they did say was that folks who ate "fried potatoes" two or more times a week "were at an increased risk of mortality". And not the kind of minuscule increase that's easy to brush off for those firmly committed to their death sticks. The researchers concluded that frequent fried potato eaters more than doubled their risk of premature death.
The ray of hope for tuber lovers? "The consumption of unfried potatoes was not associated with an increased mortality risk," the study noted. No word if those unfried potatoes were drenched with butter, slathered with sour cream and sprinkled with pre-shredded cheddar.
Everyone, of course, cried fryer-oil tears over the news.
But the truly aggrieved party was the National Potato Council, based in Washington. John Keeling, the organisation's chief executive, released a statement saying the "study has significant methodological flaws, which have led to misinterpretations of the data".
Among the council's complaints: The participants were taken from a study on osteoarthritis, which meant the subjects either had osteoarthritis of the knee or were at high risk for it. This population, the council argues, "cannot be generalised to other populations".
The council also noted that the participants were asked to fill out a single questionnaire in the "year preceding the start of the study . . . No other attempt was made to record the participants' dietary patterns in the entire intervening eight years of the study."
"Based on these data, it is very much of a stretch to brand fried potatoes, or any other form of potato, as unhealthy," Keeling said in his statement. "The food consumption reported in the study may not have reflected usage over the course of the lifetime, further illustrating the danger of branding potatoes (or any other food item) as being unhealthy or healthy in the context of this study."
Keeling went on to promote the nutritional value of potatoes, which, of course, is his job.
Veronese did not dispute some of Keeling's charges, agreeing that the research subjects were taken from a study on osteoarthritis and that the one-time questionnaire does have "some limitations". But Veronese said such one-off questionnaires are "common" to long-term studies. What's more, the researcher added, osteoarthritis subjects share similar characteristics with the general population in the United States. "Our findings," Veronese emailed, "would be similar in other populations, but other studies are needed of course".
Marion Nestle, professor of nutrition, food studies and public health at New York University, wasn't so alarmed by the study's results.
"First, this is an association," Nestle emailed. "Fried potatoes are associated with somewhat higher mortality, but this does not mean that they cause death. People who eat a lot of fried potatoes might have other unhealthy lifestyle practices - they might have worse diets in general, not exercise, smoke more or drink more."
"Second," Nestle added, "the association is not strictly dose-related. At lower levels of intake, the association is not statistically significant. The most significant associations are at the highest levels of intake of fried potatoes - three times a week or more. The moral here is moderation. If you love french fries, make them a once-in-a-while treat."
You're welcome, internet.