Coconut oil has "undeserved health halo," dietitian says A controversial lecture on nutrition calls into question the health claims for coconot oil. A Harvard adjunct professor called the oil "pure poison." Coconut oil's superfood status was challenged last year when the American Heart Association recommended limited use of the saturated fat. Samantha Heller, a registered dietitian at NYU Langone Health, joins "CBS This Morning" to discuss how the oil, like butter and lard, can raise your levels of bad cholesterol.