Schizophrenia ‘helped the ascent of man’. ‘Tiny mutations in our ancestors’ brain cells triggered mankind’s
takeover of the world 100,000 years ago. But these changes
also cursed our species to suffer from schizophrenia and
depression.

This is the controversial claim by biochemist David Horrobin in a
new book, The Madness of Adam & Eve: How schizophrenia
shaped humanity, to be published by Bantam Press next
month.

Horrobin – who is medical adviser to the Schizophrenia
Association of Great Britain – argues that the changes which
propelled humanity to its current global ascendancy were the
same as those which have left us vulnerable to mental disease.’ Horrobin lists families sharing great creativity and madness — Jung, Einstein, Joyce, etc. — and geniuses considered to be mentally imbalanced. I’d love to see his statistical reasoning, without which it feels like sampling bias to me. Most dicey, however, seems his assertion that the critical mutation involved the fat content of human neural tissue. He argues that the transition to an agriculturally-based diet altered the fat content of our food and left us vulnerable, as our hunter-gatherer ancestors hadn’t been. Although I haven’t read the book, and am arguing only with the blurb, there appear to be several problems with his thesis. First, he appears to lump together all major mental illnesses, not explaining their very real differences. Second, this doesn’t explain why some people get the illnesses and others do not; why no one has ever found the association between a high-fat diet and relative immunity to schizophrenia (or an inverse relationship between vulnerability to heart disease and mental illness…) his theory would seem to predict; or differences across populations with very differing diets. But, then again, until recently he was the managing director of a company promoting essential fatty acid natural dietary supplements. The Guardian