Q:Dear Lynne, I read your very interesting special report in Volume 3 Number 5 on cataracts without surgery, and was surprised to find that the value of chromium was not mentioned.

As cataracts are so common as a complication of diabetes and insulin metabolism can be helped so much by chromium supplementation, it seems reasonable to think that chromium could be helpful in the prevention of cataracts. Indeed a study has shown (I cannot put my hand on the reference at present) that in a group of diabetic susceptible rats chromium supplements can prevent the development of cataracts.In the wonderful book that is now difficult to obtain, The Trace Elements and Man, by Henry A. Schroeder, M.E., (Devin-Adair, 1973), he comments that in 1959 Claus Schwarz and Walter Mertz (who is alive and well today, and well respected for his work on chromium) had done a number of experiments on rats. "Another interesting change occurring in chromium deficient old rats is the development of opacities of the cornea of the eye. There is a concentration of chromium in the cornea as in the skin. Opacities and vascularization were found quite frequently by Mertz and by us," he says.

In the proceedings of the third International Congress on Trace Elements in Medicine Biology, volume 32, complete January-March 1992, (edited by Gerhart D. N. Schrauzer) a paper is presented by Pineau and colleagues which quite clearly shows the lower levels of chromium in the lenses of diabetic patients with cataracts. Kind regards, Dr Patrick J Kingsley, Osgathorpe......

A:Dear Dr Kingsley: Thank you for sharing this information with us. Readers: see cover story this month for the effects of chromium supplementation on diabetes.