visual symptoms. Risk factors Key risk factors are age, race/ethnicity, smoking, and family history. Advanced age is the strongest predictor of AMD, particularly over 50. Race and ethnicity As illustrated by the Figure in this section, derived from data presented by the National Eye Institute of the United States, among those over 80 years of age, White individuals are more than 6-fold more likely to develop AMD than Black or Hispanic individuals. Thus, white background is a major risk factor for AMD. In Caucasian (White) skin, there is a specific group of polymorphic genes (with single nucleotide alterations) that encode for enzymes and transcription factors responsible for the early steps (including the first step, formation of L-DOPA from the amino acid tyrosine) of the melanin synthesis pathway. Many of these enzymes and transcription factors are reviewed by Markiewicz and Idowu. Also, as reviewed by Sturm et al. “increasing intracellular concentrations of either tyrosine or L-DOPA both result in an increase in melanogenesis” or formation of the black pigment melanin. Thus there appears to be an association between reduced L-DOPA production and white skin. As suggested by the Figure and information in this section, reduced L-DOPA, resulting in white skin, appears to be associated with an increased risk of macular degeneration for white individuals over the age of 80. Environment and lifestyle Smoking: Smoking tobacco increases the risk of AMD by two to three times that of someone who has never smoked, and may be the most important modifiable factor in its prevention. A review of previous studies found "a strong association between current smoking and AMD. ... Cigarette smoking is likely to have toxic effects on the retina." Hypertension (high blood pressure): In the ALIENOR study 2013, early and late AMD were not significantly associated with systolic or diastolic blood pressure (BP), hypertension, or use of antihypertensive medications, but elevated pulse pressure [(PP) systolic BP minus diastolic BP] was significantly associated with an increased risk of late AMD. Atherosclerosis High cholesterol: Elevated cholesterol may increase the risk of AMD Obesity: Abdominal obesity is a risk factor, especially among men Fat intake: Consuming high amounts of certain fats, including saturated fats, trans fats, and omega-6 fatty acids, likely contributes to AMD, while monounsaturated fats are potentially protective. In particular, omega-3 fatty acids may decrease the risk of AMD. Exposure to UV light from sunlight is maybe associated with an increased risk