They work by interfering with pain messages traveling through the nervous system. Endorphins cut off the pain message, stopping it dead in its tracks. Unfortunately, we can't use the endorphins themselves as pain killers. Fortunately, we don't have to take endorphins in order to enjoy their pain-killing benefits. Instead, we can use natural substances that protect or boost the endorphins in our bodies, allowing their levels to rise to higher, more powerful levels.
Tyrosine is a nonessential amino acid that is manufactured by the body or absorbed from food.
The body uses tyrosine to make the neurotransmitters dopamine, norepinephrine, and epinephrine, all of which play a role in elevating mood and keeping us alert. The difference between the forms is like the difference between your hands. They're identical but opposite, mirror images of each other. This is the form in which phenylalanine is normally found in foods. This is the form that protects endorphins in our bodies and helps us to fight pain and depression.