How's this for easy? Check out those nails. If you see white spots, that's indicative of a zinc deficiency. It could mean... just low zinc, or if Pyroluria, which also binds B-6, can induce HDD symptoms. Supplement with sunflower seeds for zinc, and the P-5-P form of Pyridoxine/B-6; and avoid Omega 3 oils if you suspect Pyroluria.