Hemoglobin: The oxygen-carrying pigment and predominant protein in the red blood cells. Hemoglobin forms an unstable, reversible bond with oxygen. In its oxygenated state it is called oxyhemoglobin and is bright red.
Caffeine by McDonalds Iced Coffee Size. 1  Medium (16 floz): 133mg. 2  Large (22 floz): 200mg. 3  Extra Large (32 floz): 320mg.
Consumer Reports magazine tested 27 popular energy drinks -- including Red Bull, Rockstar, and Starbucks Double Shot -- finding that caffeine levels ranged from 6 milligrams to 242 milligrams per serving -- which can be confusing for consumers.