Africans display highest median heterozygosity ratio of 1.95. East Asians show lowest heterozygosity ratio of 1.31. Europeans have intermediate heterozygosity ratio of 1.55. African-European admixed offspring reach peak heterozygosity ratio of 2.16. South Asians cluster genetically closer to Europeans than East Asians. Admixed populations exhibit highest variation in heterozygosity ratio. Heterozygosity ratio strongly anticorrelates with runs of homozygosity. Heterozygosity ratio robust across genotyping densities unlike ROH. Higher heterozygosity ratio increases height by 5.43 cm per unit in Europeans. Association persists after adjusting for known height SNPs. Effect stronger in European females. No height association in Africans or Asians due to low power. Higher heterozygosity protects Europeans from amino acid transport disorders, oral abscesses, renal colic, extremity wounds. Higher heterozygosity protects Africans from iron deficiency anemia. African genetic diversity drives more alternative alleles than other groups.