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Lack of vitamin B12 triggers fatigue during daytime and sleeping problems at night

Lack of vitamin B12 triggers fatigue during daytime and sleeping problems at nightNothing beats a good night’s sleep. Still, sleep disturbances are widespread, and surprisingly many people struggle through the day, trying to survive on far too much coffee and other stimulants – and they cannot do anything about the problem. It turns out that many vegetarians, users of birth control pills, older people, and diabetics suffer from sleep problems because they lack vitamin B12. A vitamin B12 deficiency may also affect the nervous system and memory so it is vital to get enough of this nutrient.

It was thought earlier that only strict vegetarians and vegans were at risk of vitamin B12 deficiency because this nutrient is primarily found in animal food sources. However, science has grown wiser and realizes today that many other groups are affected. It is now estimated that about one in four Americans over 60 years of age lacks this vital vitamin, and a similar pattern is bound to be seen in the rest of the western world. One of the reasons is that our ability to absorb the vitamin from food or supplements decreases, as we grow older. Too little gastric juice and overconsumption of alcohol, hormone pills, and sleeping pills may also impair our ability to take up the vitamin from the digestive tract. Recent studies even show that around 20 percent of those taking metformin for their type-2 diabetes are deficient (or borderline deficient) of vitamin B12.

Vitamin B12’s daytime and nighttime functions

  • Production of red blood cells that carry oxygen to all parts of the body
  • Burning of fat and carbohydrate (cellular metabolism)
  • Energy levels
  • Nervous system and mental balance
  • Production of melatonin (sleep hormone)
  • Immune system
  • Conversion of the amino acid homocysteine to methionine

Lack of vitamin B12 affects the nervous system and sleep quality

Lack of vitamin B12 may affect one or several functions in which the vitamin is involved, where the turnover of fat and carbohydrate and the nervous system play important roles. Lack of vitamin B12 may easily cause fatigue, poor concentration, impaired memory, mood swings, and sleep disturbances.

Incomplete diets and poor absorption

As mentioned, vitamin B12 is mainly found in animal food sources with the best sources being liver, meat, and fish. Somewhat smaller amounts are found in eggs and dairy products. This is why vegetarians are at increased risk of getting too little of the nutrient. In India where the majority of people are vegetarians, a staggering 80 percent of the adult population lacks vitamin B12, and that has widespread consequences for their health.
Not only vegetarians are at risk. It turns out that the uptake of vitamin B12 from food requires the presence of a protein called intrinsic factor, which the stomach mucosa manufactures. The ageing process may easily impair our digestion and our ability to produce intrinsic factor, which is vital for our ability to absorb vitamin B12. Too little gastric juice, a problem that many older people suffer from, and the use of antacids, may also compromise the ability to absorb vitamin B12. Overconsumption of alcohol, use of birth control pills, hormone pills during menopause, sleeping pills, and metformin against type-2 diabetes may even reduce the ability to absorb or utilize the vitamin. The same is the case with infections caused by the Helicobacter pylori bacteria that can lead to stomach ulcers.

Did you know that poor memory, mental lethargy, dementia, and sleep disturbances are often associated with ageing processes without proper vitamin B12 treatment?

Blood samples and diagnosis

A vitamin B12 deficiency is easy to detect by means of a blood sample. Lack of vitamin B12 is often seen in combination with folic acid deficiency.

Supplements and injections

You get the best utilization of vitamin B12 supplements if you have plenty of gastric juice. Supplements should ideally be taken in combination with folic acid and other B vitamins that work in synergy with vitamin B12. Vitamin B12 supplements should not be taken at the same time as antacids and other acid-neutralizing agents such as baking soda.
It is generally more difficult to absorb vitamin B12 than other nutrients. As we grow older, this ability continues to decrease.
The synthetic form of vitamin B12 called cyanocobalamin is often used in supplements. The doses are often rather high in order to ensure proper uptake.
In some cases such as pernicious anemia, vitamin B12 is given as injections.

Lack of vitamin B12 may turn into a vicious cycle

because it may cause sleep disturbances, and sleeping pills exacerbate the deficiency

Other useful advice for better sleep

  • eat a coarse, green, and balanced diet
  • maintain stable blood sugar levels
  • make sure to get enough magnesium
  • avoid coffee and other caffeinated beverages after 4 PM
  • get plenty of daylight, exercise, and fresh air
  • sleep in complete darkness without any form of electrosmog pollution
  • consider taking a melatonin supplement (our melatonin levels decrease with increasing age)


Mercola: ”You May Sleep Better at Night by Taking Vitamin B12 During the day.”

Vanita R Aroda et al. Long-Term Metformin Use and Vitamin B12 Deficiency in the Diabetes Prevention Program Outcomes Study. Endocrine Society 201

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