Extrapolation, much?
Headline: Research has found that Marmite could help prevent dementia
Research article: A group of 28 adult volunteers (10 males, mean age 22 years) completed the study after providing written informed consent.
We could just stop there, but it gets better (not better)
The study found that the people getting Marmite had, as hypothesised, less response by their brains to flickering visual stimuli. The research paper does not mention dementia (or memory, or Alzheimers). At all. It concludes
“This demonstrates that the balance of excitation and inhibition in the brain can be influenced by dietary interventions, suggesting possible clinical benefits in conditions (e.g. epilepsy) where inhibition is abnormal.”
Even the story doesn’t come close to the headline claims, saying just
It could also prompt further research to see if Marmite, and its effect on the brain’s GABA chemical, might provide a treatment for dementia.
And, right at the end of the story, the quote from an independent expert
“there’s no way to say from this study whether eating Marmite does affect your dementia risk.
If it does, and if that’s because of the vitamin B12, it might also have been worth mentioning that there are other foods with as much or more vitamin B12 per serving, such as beef, and lamb, and many types of fish.
Thomas Lumley (@tslumley) is Professor of Biostatistics at the University of Auckland. His research interests include semiparametric models, survey sampling, statistical computing, foundations of statistics, and whatever methodological problems his medical collaborators come up with. He also blogs at Biased and Inefficient See all posts by Thomas Lumley »