Jaundice Vitamin D production. Bilirubin count is lowered through bowel movements and urination, so frequent and effective feedings are especially important. Yellow discoloration of the skin, especially on the palms and the soles, but not of the sclera or inside the mouth is due to carotenemia—a harmless condition. Jaundice itself is not a disease, but rather a sign of one of many possible underlying pathological processes that occur at some point along the normal physiological pathway of the metabolism of bilirubin in blood. When red blood cells have completed their life span of approximately 120 days, or when they are damaged,
Human skin color "Val60Leu" (rs1805005) and "Val92Met" (rs2228479) have been associated with reduced tanning response in European and/or East Asian populations. These alleles show no signs of positive selection and only occur in relatively small numbers, reaching a peak in Europe with around 28% of the population having at least one allele of one of the variations. A study of self-reported tanning ability and skin type in American non-Hispanic Caucasians found that "SLC24A5 Phe374Leu" is significantly associated with reduced tanning ability and also associated "TYR Arg402Gln" (rs1126809), "OCA2 Arg305Trp" (rs1800401) and a 2-SNP haplotype in "ASIP" (rs4911414 and rs1015362) to skin type variation