Diabetes and gluten

admin March 12, 2017 3 Comments

Gluten-free food: not around in the 80s

If we’re to believe all the headlines from the last few days, a gluten-free diet increases your risk of developing type 2 diabetes. We read those screamers in the Express, the Independent, the Times, and the Telegraph, among many others — including the New Scientist.

Meanwhile, The Conversation — “Academic rigour, journalistic flair” — went further, trumpeting that “gluten-free food is not the healthy option and could increase your risk of diabetes”.

The source for this news was as-yet unpublished work presented to a recent American Heart Association meeting by Harvard University nutrition researchers. You can read a round-up of that, from the AHA itself, right here.

Most noticeable, of course, is the AHA’s headline. “Low gluten diets may be associated with higher risk of T2D …” — a low gluten diet is not a gluten-free diet.

The study was huge — 200,000 people, gleaned from three previous long-term studies, which had begun in the 1980s, and using data derived from the periodic completion of food-intake questionnaires by participants themselves every three years or so. From this vast quantity of material, Harvard researchers had to estimate gluten intake: most consumed less than 12g/day, with averages around 6-7g/day. When adjusting for wheat fibre intake — known to be protective for T2D — researchers found that:

” … individuals in the highest 20 percent of gluten consumption had a 13 percent lower risk of developing Type 2 diabetes in comparison to those with the lowest daily gluten consumption (approximately fewer than 4 grams)”

Self-reporting by participants obviously has scientific limitations, and researchers say that further studies are needed.

The study did not look at modern-day gluten free foods, which were barely available when the records used began.

The study did not look at those following gluten-free diets — typically lower than 0.005g a day — which were hardly known of at the time, and researchers made no statement about gluten abstention.

Researchers did not say ” … those who cut gluten out of their diet increase the risk of developing diabetes” — as the BBC claimed, along with many others, including some of those mentioned in the first paragraph above.

This was about consumers who just happened to be on the lower end of the gluten-consuming spectrum, living at a time when most did not know what gluten was, let alone how to avoid it.

I guess, though, that doesn’t make much of a story to shout about through the media — be it journalistic or social — when it’s far more profitable to add more misinformation to the slushpile of gluten confusion, and more entertaining to use that to have a pop at the hipsters who order the quinoa or ‘dieters’ who demolish trays of sweet potato chocolate brownies.

Notes / Further Reading

Thanks to Amy Ratner for alerting me to the point that this research did not cover GFDs.
Healthline covered the news more accurately, but RD quoted assumed participants aimed to restrict gluten. Click here. 
Popular Science’s take was also more thoughtful and considered than the average. Click here. 
Coeliac UK issued a brief statement on the research. Click here.