Can Yoga Leggings be Used as Long Underwear?

Can Yoga Leggings be Used as Long Underwear? It is reluctantly OK to wear yoga leggings as long underwear. But long underwear has better heat retention, which is the main property of long underwear. And the main property of yoga leggings is tight fitting and air permeable. If necessary, special long underwear is recommended. And non cotton yoga leggings or yoga leggings with complicated decoration are note recommended to wear inside. If the yoga leggings are too tight, it is not good for blood circulation.