Taurine is an amino acid good for the heart
Taurine is important for the normal physiological functions of the heart, brain and the retina in the eye. It is also required for reproduction and immunity.

Tyrosine is a non-essential amino acid L-tyrosine is used to synthesize many neurotransmitters in the brain.

  Tyrosine is an amino acid that is used in protein construction. Taurine is similar to an amino acid but is not a component of any protein -- it is a "free agent" with many other roles (very important roles) in physiology. Tyrosine is used in building some neurotransmitters (e.g. dopamine) and hormones (e.g. thyroid).

  The Taurine in this supplement is synthetic and not from an animal source.

  plant

  Considering the fundamental importance of taurine in physiology, it would be surprising if eliminating taurine deficiency did NOT have some benefit against juscle cramps. I say deficiency because US diets are almost always deficient in taurine (compared to the Okinawan diet, for example). However, much depends on the reason for the cramps. Impaired circulation due to impaired vascular endothelia can be improved by taurine. Lack of substances to produce NO (nitric oxide) might also be relevant -- arginine and citrulline can remedy that. Muscle spasms due to magnesium deficiency is another possibility. In any case, be sure to take adequate AMOUNTS of taurine -- not milligrams, but GRAMS, maybe s or 3 grams, several times per day. Likewise for arginine and citrulline, maybe 2 grams each a couple of times per day.

  magnesium does

  (This is a good question, because the label information rules out the presence of various allergens and possible toxins, but does not mention soy.) The synthetic production of taurine seems to have nothing to do with soy; synthetic taurine is created in a laboratory by inducing of a chemical reaction.

  to the best of my knowledge, it does not contain soy. Soy is not listed as an ingredient in "Supplement Facts"