Tonic water and is used mostly for its flavor. As a result of the lower quinine content, it is less bitter, and is also usually sweetened, often with high-fructose corn syrup or sugar. Some manufacturers also produce diet (or slimline) tonic water, which may contain artificial sweeteners such as aspartame. Traditional-style tonic water with little more than quinine and carbonated water is less common but may be preferred by those who desire the bitter flavor. In the United States, the US Food and Drug Administration (FDA) limits the quinine content in tonic water to 83 ppm (83 mg per liter if calculated
Human genetic resistance to malaria Human genetic resistance to malaria Human genetic resistance to malaria refers to inherited changes in the DNA of humans which increase resistance to malaria and result in increased survival of individuals with those genetic changes. The existence of these genotypes is likely due to evolutionary pressure exerted by parasites of the genus "Plasmodium" which cause malaria. Since malaria infects red blood cells, these genetic changes are most commonly alterations to molecules essential for red blood cell function (and therefore parasite survival), such as hemoglobin or other cellular proteins or enzymes of red blood cells. These alterations generally protect red blood