Vitamin B12 deficiency.
Do you suffer from any of the following symptoms?
Fatigue, tiredness, or light-headedness
Rapid heartbeat or difficulty breathing
Poor memory or difficulty concentrating
Numbness and tingling of hands or feet
Difficulty with balance, poor coordination
Easy bruising or bleeding gums
Unexplainable weight loss
Depression, irritability, paranoia, mania, hallucinations.
Could be you have a vitamin B12 deficiency.