Elias MF, Elias PK, Sullivan LM, Wolf PA, D’Agostino RB. Lower cognitive function in the presence of obesity and hypertension: the Framingham heart study. Int J Obes Relat Metab Disord. 2003 Feb;27(2):260-8.

The number of male participants is incorrectly cited in the BBC article, but the overall number of participants does tot up to roughly 1400.

La Wade is, as always, on the money: there’s plenty of research supporting the notion that obesity is among the risk factors for vascular dementia, and is plausibly on a proposed (much-forked, multivariate) causative pathway. The Framingham Heart Study is a well-respected and very longstanding (fifty years and counting) cohort study run jointly by the National Heart, Lung, and Blood Institute and Boston U. In this use of the data, the investigators wanted to see whether the existing observations about obesity and neurological damage from altered cerebral blood flow and microvascular damage were, as the mechanism seems to suggest, associated with an increased risk of measurable cognitive loss among people without clinical dementia and with and without hypertension (to see where obesity and hypertension interacted.)

The “what of the children” comment, taken in the context of FHS, is probably best interpreted literally: if obesity results in increasing neurologic damage over time, with or without hypertension, then the longer that people live with obesity, the greater the deficits are likely to be, so obese children who never shed the weight are likely to be at most risk.

BTW, Harvard jealousy is unlikely given that Dr. Elias has been at University of Maine for the past 30 years (he’s a collaborator with FHS – but he runs the Maine-Syracuse Longitudinal Study, which is also old and well-respected and a source of a lot of our understanding of how cardiovascular disease works in the real world.) Also, Ivy League jealousy isn’t as common at the advanced-degree level of public health as it is at the general undergrad level, probably because the pissing matches are so different.

And K, these studies are looking at relationships between lifetime obesity and long-term risk of poorer neurocognitive performance, not the effects of gaining a few pounds over the course of a year. Of course you’re right that education doesn’t lower IQ, and in fact it has actually been found to reduce your risk of neurodegenerative disease such as Alzheimer’s (although again, that is just a correlation, not an established causal relationship). But I have to disagree with your quote–exercise has been found to improve mental performance both in the short and long term. And college students who participate in varsity sports have been shown to have higher GPAs and higher rates of graduation. So it might actually be worth it, intellectually and academically, to put the studying on the back burner once in a while!

Yes, thank you! That’s exactly what I couldn’t quite put my finger on. Also, the fact that there’s no University of Boston is pretty amusing.

I used to have a quotation stuck to my computer which said (from memory) “Exams are passed on coffee and chocolate. It is impossible to have a finely honed mind and a finely honed body.”

Then I decided it was defeatist and chucked it out. But nonetheless, I don’t have nearly so much time to exercise since I started graduate school…

That’s not a false correlation, but the one in the article definitely IS.

Many, many risk factors.

But of course all that is very different from saying that all obese people are stupid, and I agree with Mo that this headline was inflammatory. There are many risk factors for dementia, including certain genes, and I can’t imagine any newspaper running a headline saying “People with APOE-e4 gene variant have lower IQs.”

I know, right? CORRELATION DOES NOT EQUAL CAUSATION.

I’m sure I rant about the lack of critical thinking in our culture too much.

Naaahhh.