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Type O with Depression


I am 55 yr old woman with O+ and long history of recurrent major depression. Your suggestion to excercise vigorously, rather than just walking has improved my sense of well being. However, your site only speaks against St John's Wort. Am wondering whether you suggest any natural herbs for depression in Type O's? Thanks for all of your research and availability here. Do see that my body prefers type O foods for the most part. Craving sweets remains a problem though. Thanks again.


Type O's have lower levels of the enzyme MAO, and St. Johns Wort is an MAO inhibitor. This perhaps explains why many type Os on St Johns Wort say they feel "weird" or have disturbing dreams. I have however been finding that type O's with mild to moderate depression do benefit from the amino acid tyrosine (which can boost dopamine levels), and arginine (which is used to recycle nitrous oxide in the nervous system). Also, the gene for the enzyme dopamine beta hydroxylase sits right on top of the ABO gene and there are indications that this may cause psychiatric syndromes to be somewhat related to ABO blood group. Maybe those Japanese personality observations were not so off-the-wall after all? It is interesting that dopamine, a chemical which is closely linked with sense of well-being, when defficient also produces hypoglycemia, which you allude to at the end of your question. Perhaps even more interesting is that the chemical structure of dopamine resembles the ABO antigens.

What does blood type have to do with neurotransmitters and the neuro-hormonal response to stress? While the use of blood type as a determinant of personality traits has been prevalent in Japan, a lack of tangible scientific facts had relegated these cultural beliefs to the realm of fantasy. However, an increasing amount of evidence indicates that individuals of differing blood groups have extremely different responses to the same stressor. Equally surprising, the genetics of blood group also appear to alter your susceptibility to developing certain neuro-psychiatric disorders. Even the response to inhaled nitric oxide seems to be modulated along the lines of blood type.

Stress, brain chemicals, nitric oxide; the common ground these disparate observations share is that all are dependent on neuro-hormonal signals to moderate an appropriate response to environmental factors. This is where science meets magic, because these neuro-hormonal signals are all mediated by the availability of certain nutritional building blocks and the activity of specific enzymes to catalyze the transformation of neurotransmitters and stress hormones.

Supplement-wise, I've found that type O's with mild to moderate depression can do very well with additional levels of the amino acid L-TYROSINE (1) and the B vitamins FOLIC ACID (2) and METHYLCOBALAMIN, or "Active B12". (3)

Through the miracle of the human genome project, it has become possible to explore the very fabric of human genetics. Evidence indicates the gene that controls blood type expression is probably also linked to and controls inheritence of the genes that code for the activity of dopamine-beta hydroxylase, catechol-O-methyl transferase, and arginosuccinate synthetase. Coincidentally, these are all enzymes that influence our neuro-hormonal response to environmental factors.

1. Meyers S. Related Articles Use of neurotransmitter precursors for treatment of depression. Altern Med Rev. 2000 Feb;5(1):64-71. Review.

2. Lee S, Wing YK, Fong S. A controlled study of folate levels in Chinese inpatients with major depression in Hong Kong. J Affect Disord. 1998 Apr;49(1):73-7.

3. Kelly GS. Folates: supplemental forms and therapeutic applications. Altern Med Rev. 1998 Jun;3(3):208-20. Review.

The Ask Dr. D'Adamo internet advice column ran from 1996 to 2009, at which time Dr. D'Adamo's teaching and programming responsibilities no longer allowed him to devote time and resources to directly answering visitor questions. However we've recently reorganized this treasure-trove of material and made it again available to his readership. He occasionally posts new entries. These are marked with a NEW tag.

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