Epidemiological and intervention studies suggest that lutein may act as a nutritional factor able to modulate visual performance as well as the processes implicated in the pathogenesis and progression of degenerative eye diseases. Since lutein cannot be synthesised by the body, and daily dietary consumption is generally below the level of intake found to be beneficial in clinical studies, increased consumption – through diet or supplementation ߝ is recommended. The prerequisites for lutein to benefit the eye are: release from the food or food supplement matrix in which it is included; absorption by the intestinal cell; presence in adequate concentrations in serum; and deposition of serum lutein into the macula of the eye. Not all lutein ingredients are alike so, when recommending eye supplements to patients, in addition to looking for safe products, it is critical to ensure that the lutein ingredient used is absorbed properly by the body and has proven its efficacy in clinical trials.