There is now strong evidence that Alzheimer's could be caused by the very same choices that cause type 2 Diabetes; poor diet loaded with fat, sugars and salt. The brilliant George Monbiot writing in The Guardian has written an extensive essay using the most current research to come to the strong conclusion that we could be facing an epidemic of "brain diabetes" in the future if our uncontrolled appetite for junk and fast food is not curbed.
But this problem belongs to all of us. Even if you can detach yourself from the suffering caused by diseases arising from bad diets, you will carry the cost, as a growing proportion of the health budget will be used to address them. The cost – measured in both human suffering and money – could be far greater than we imagined. A large body of evidence now suggests that Alzheimer's is primarily a metabolic disease. Some scientists have gone so far as to rename it: they call it type 3 diabetes.
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About 35 million people suffer from Alzheimer's disease worldwide; current projections, based on the rate at which the population ages, suggest that this will rise to 100 million by 2050. But if, as many scientists now believe, it is caused largely by the brain's impaired response to insulin, the numbers could rise much further. In the United States, the percentage of the population with type 2 diabetes, which is strongly linked to obesity, has almost trebled in 30 years. If Alzheimer's, or "type 3 diabetes", goes the same way, the potential for human suffering is incalculable.
It seems that almost daily we receive more evidence that the food choices we make can have a profound effect on not only our own health but on some of the most serious issues of our time including
climate change (pdf) and the depletion of our land and
water supplies.
The association between Alzheimer's and type 2 diabetes is long-established: type 2 sufferers are two to three times more likely to be struck by this form of dementia than the general population. There are also associations between Alzheimer's and obesity and Alzheimer's and metabolic syndrome (a complex of diet-related pathologies).
The evidence is strong and growing. But if ever there was a case for the precautionary principle, here it is. It's not as if we lose anything by eating less rubbish.