BACKGROUND Cataract is one of the age-related eye disorders due to the opacity in the lens and accounts for 50% of blindness in India. Factors like family history, ageing, alterations in blood electrolytes and diabetes mellitus are involved in formation of senile cataract. Alterations in serum electrolyte levels can induce alterations in the concentration of electrolytes in aqueous humour, which affect the lens metabolism and probably lead to the formation of senile cataract. The aim of the study is to evaluate the effect of the altered levels of serum electrolytes and the risk in development of senile cataract.