Lutein is a natural component of the retina that is acquired in the diet; One of its multiple functions is to capture reactive oxygen species and promote their elimination. People with Diabetes Mellitus have a significant increase in oxidative stress due to protein glycation and activation of the polyol pathway; as a result, they develop diabetic retinopathy that can progress to macular edema and cause severe visual disturbances including central blindness. The lack of lutein in people with macular edema is evident, therefore, they require additional consumption to prevent and reduce the complications. We decided to undertake a review in order to learn more about this supplement, its properties and its beneficial effect on the eyesight of individuals with Diabetic Macular Edema.