Vitamin B 6 or Pyridoxine is a B complex Vitamin. It is involved in the metabolism of food and production of energy. It supports the functioning of Brain and is involved in the production of various hormones. It is a part of the RBC production process and cells that form the Immune System.

Daily requirement of Vitamin B 6 in the body
0 to 6 months : 0.1 mg
7 to 12 months : 0.3 mg
1 to 3 years : 0.5 mg
4 to 8 years : 0.6 mg
9 to 13 years : 1 mg
14 to 18 years (Boys / Girls ) : 1.3 / 1.2 mg
19 to 50 years : 1.3 mg
Above 51 years ( Men / Women ) : 1.7 / 1.5 mg
Pregnant / Lactating : 1.9 / 2.0 mg

Functions of Vitamin B 6 in the body
Vitamin B 6 is needed for the development and functioning of the Brain. It is involved in the manufacturing of several neurotransmitters. It produces mood and body clock regulating hormones like serotonin, melatonin and norepinephrine.
With adequate amount of Vitamin B 6 the body is able to absorb Vitamin B 12 better. Vitamin B 6 improves Cognitive functions and prevents the occurrence of Heart diseases and Cancer. It reduces PMS symptoms like
Anxiety
Bloating
Mood Swings
Irritability
Forgetfulness

Deficiency of Vitamin B 6 causes
Depression
Nervousness
Irritability
Weakness in Muscles
Short Term Memory loss
Unable to Concentrate on the task

Excess of Vitamin B 6 causes
Long term and excessive intake of Vitamin B 6 may cause :
Pain
Nausea
Heartburn
Nerve damage
Skin patches
Sensitivity to Sunlight