December 26, 2016

The aluminium scare

I hold no brief for aluminium. Claims that molecules from aluminium pots and pans leak into food go back a long way so I have never liked aluminium cooking utensils. I have mostly used cast-iron, enamel and steel utensils instead. But the study below has been hyped and I wish to inject a note of caution.

The main cautions concern the sample, its selection, its size  and the variability of the results.

Regarding the latter, I quote from the Results section of the paper:  "Aluminium was found in all 144 tissues and its concentration ranged from 0.01 to 35.65 ?g/g dry wt."  That is a pretty big variation. It does not sound like a uniform process.

And the form of Alzheimers was a rare one.  Does it generalize to other forms?  Is the rarity due to something that also encourages aluminium concentrations? Might not more common forms of Alzheimers be less troubled by aluminium?

And the sample is an available one, not a random one so its generalizability is inherently unknown.

And the sample size is risible.  You can get all sorts of odd and unreplicable results with such a small sample.

Finally, an important question is how many users of aluminium pots and pans have lived to a ripe old age?  Hundreds of millions, I would think.  Do we balance 12 cases supporting a conclusion agains millions not supporting it?

I accept that I may be wrong but my conclusion is that aluminium is unlikely to harm you

Aluminium in brain tissue in familial Alzheimer’s disease

Ambreen Mirzaa et al.

The genetic predispositions which describe a diagnosis of familial Alzheimer’s disease can be considered as cornerstones of the amyloid cascade hypothesis. Essentially they place the expression and metabolism of the amyloid precursor protein as the main tenet of disease aetiology. However, we do not know the cause of Alzheimer’s disease and environmental factors may yet be shown to contribute towards its onset and progression. One such environmental factor is human exposure to aluminium and aluminium has been shown to be present in brain tissue in sporadic Alzheimer’s disease. We have made the first ever measurements of aluminium in brain tissue from 12 donors diagnosed with familial Alzheimer’s disease. The concentrations of aluminium were extremely high, for example, there were values in excess of 10 ?g/g tissue dry wt. in 5 of the 12 individuals. Overall, the concentrations were higher than all previous measurements of brain aluminium except cases of known aluminium-induced encephalopathy. We have supported our quantitative analyses using a novel method of aluminium-selective fluorescence microscopy to visualise aluminium in all lobes of every brain investigated. The unique quantitative data and the stunning images of aluminium in familial Alzheimer’s disease brain tissue raise the spectre of aluminium’s role in this devastating disease.

Journal of Trace Elements in Medicine and Biology Volume 40, March 2017, Pages 30–36.




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