As far as we know, no previous research has investigated the effect of B12 on lucid dreaming. What does actually occur during lucid dreaming in the brain? How does the level of B12 change? Does lucid dreaming is detrimental or not? Vitamin B12 is one of the most crucial nutrients because B12 is involved in the function and development of the brain, nerve cells and myelin sheaths. Unfortunately, our body can’t produce our own vitamin. For this reason, we should get it from your supplement. A lucid dream is a dream that a person is aware of dreaming with consciousness. The dreamer can control its dreams and remember vividly everything about the dream. There are some cautions about lucid dreaming 6 of them stand out: o fatigue, o weakness, o anaemia, o balance problems, o cognitive difficulties, o headache. Rapid eye movement in short “REM”, is one of the stages of brain moves. During REM sleep, the body and brain go through several changes, including: o o o o irregular and rapid breathing, high heart rate, increased blood pressure, high oxygen consumption by the brain. During lucid dreaming in the REM step (after sleeping 90 minutes), the thalamus is much more active than normal dreaming. It sends the cortex images, sounds and other sensations. With vast activation of the brain, vitamin B12 requirement increases because of lucid dreaming. The level of B12 falls dramatically. After all the responses, the dreamer probably has a vitamin B12 deficiency. Lucid dreaming affects the dreamer indirectly. Contrary to general belief, lucid dreaming does not make us weak or tired, vitamin B12 plays a significant role in all the symptoms. All the detrimental sides of having a lucid dream are associated with B12 deficiency. In conclusion, lucid dreaming leads to having B12 deficiency because of high B12 usage and active brain during dreaming. The reason for having memory loss, weakness, headache, and more is because of low B12 rate.