Structure and Function of Arteries, Capillaries, and Veins. The walls of arteries and veins have three layers or tunics: 1  An outer layer (tunica adventitia) of connective tissue with collagen fibers. 2  A middle layer (tunica media) of circularly arranged smooth muscle and elastic fibers.
You might have heard that eating chocolate or greasy foods can cause acne, but these are both just myths. The truth is that food has little to do with breakouts. Acne occurs when the openings of hair follicles become blocked with oil secretions, dead skin cells and bacteria.
Some of the effects of ACV are: 1  Too much apple cider vinegar can cause low potassium levels and may lead to osteoporosis. However, this was reported in a woman who was drinking around 8 oz. apple cider vinegar a day for many years. 2  Acidic foods can weaken tooth enamel.