Phenylalanine comes in several forms as a supplement:
L-phenylalanine is an essential amino acid. It's also found in protein in the foods we eat.
DL-phenylalanine, which contains both the D- and L-forms
The progesterone in these creams can effectively travel through the skin and into the bloodstream, according to research. In one study, menopausal women used 40 milligrams of cream twice daily, placing it on their arm, thigh, breast, or abdomen. Their blood levels of progesterone were as high as when they took progesterone capsules by mouth.
Can you get progesterone naturally from foods?
Many plants make compounds similar to progesterone which may or may not function like the purified progesterone chemical. The progesterone in creams bought without a prescription is made by processing ingredients from plants, such as yams.