Snow flake cataract is produced because of :
In Diabetics, Excess Glucose freely enters the cells of eye which are highly permeable to glucose. Here glucose is reduced by Aldose Reductase enzyme to produce Sorbitol/ Polyol. Sorbitol is hygroscopic in nature and absorbs water. Swelling due to excess sorbitol in the lens will ultimate leads to Snowflake cataract.
Aldose reductase
Galactose reductase
Fructose dehydrogenase
Alcohol dehydrogenase
Galactose and fructose metabolism