It has been discovered that symptoms of vitamin B12 deficiency manifest themselves as depression, sleeplessness, numbness, pins and needles and other nervous disorders, which are taken as signs of mental decline. In elderly people these problems are often mistaken for Alzheimer's disease.
Vegetarians are particularly at risk of developing the deficiency, as the vitamin is found in meat products. They must ensure that they take a supplement. The deficiency can also occur due to the inabilty of the body to absorb the vitamin, which can lead to severe anemia, insomnia and signs of nervousness.
A large study determined that 61% of elderly people who were affected made a full recovery after they were given the supplements. The 39% who did not respond had brain damage due to the undiagnosed deficiency over a long period.
The most easily absorbed and active form of vitamin B12 is methylcobalamin which is recommended for sufferers of sleep-wake disorder.It has a positive effect on the quality of sleep and mood.
As the symptoms are not easily apparent as deficiency, it is advised that the diet contains adequate amount of the vitamin in some form.