There are many types of seaweed which have many similar properties. However, blue green spirulina is believed to have RNA which is more advantageous to the nervous system than of the other seaweeds.

The thyroid also benefits from spirulina. If you have a weakened thyroid, it may compete for the nutrients in the spirulina. Therefore, I would add more spirulina if you have the very first symptom of a weak thyroid.

This can be determined by the moons of the fingernails.

If you are 100 to 150 pounds, I would take 6 spirulina plus 1 extra for every 2 moons which are missing. I would also add 1 additional spirulina for every 50 pound of body weight.