The uMMA test was found to have 100% sensitivity (if the person is B12 deficient the test is positive) in identifying less obvious B12 deficient hospital patients. ^17,18 (Normal uMMA was less than 5.0 micrograms MMA per milligram creatinine).

Using the uMMA test to screen non-anemic senior populations, 49% of the 35 subjects found to be B12 deficient had a normal serum B12 level. uMMA levels normalized with B12 injections.¹⁴ (Normal uMMA was less than 5.0)

     Using the uMMA test to screen a vegetarian population (N=54). 43% (23/54) had abnormally high uMMA levels indicating metabolic B12 deficiency. Of those found B12 deficient with the uMMA test, 83% (19/23) had a normal serum B12 level. uMMA levels normalized with adequate B12 therapy.⁵ (Normal uMMA was less than 4.0)

     B12 deficiency is the only know cause for high uMMA except for a rare, life-threatening enzyme deficiency which is evident early in life.

     In a screening study, high uMMA levels dropped markedly on all 16 subjects who were treated with vitamin B12 replacement.¹⁴

     In a study of hospital patients with vitamin B12 deficiency, the uMMA test specificity
(the person is deficient if the test is positive) was found to be 99%.^17,18

     A convincing study of the value of the uMMA test showed the reduction of uMMA for vegetarians receiving sublingual B12 ( p<0.01) and nutritional yeast (p<0.05) but not those receiving probiotic food (p>0.2).⁵ B12 deficiency can developed in 2 years on diet.⁵