Ensuring your body receives enough vitamin B-12 is integral to the production and maintenance of healthy red blood cells, the upkeep of neurological function and sustaining a healthy nervous system.
Luckily, most people receive enough vitamin B-12 from their diet alone and don't necessarily require supplementation; the vitamin is present in many staple foods. But it's still a good idea to be mindful of how much vitamin B-12 you're getting and when is the most appropriate time for your body to absorb it, especially if you are taking supplements.
Why Is Vitamin B-12 Needed?
Vitamin B-12 is a nutrient integral to many functions of the human body. The National Institutes of Health explains that vitamin B-12 is necessary for keeping red blood cells and nerves healthy, and is additionally helpful in the production of DNA — the genetic material present in all cells.
Furthermore, a severe deficiency in vitamin B-12 contributes to a specific deficiency known as megaloblastic anemia, which can cause tiredness, weakness and progressive damage to the body.
Symptoms of Vitamin B-12 Deficiency
The symptoms of vitamin B-12 deficiency can be subtle, and may be minuscule or not occur at all in some of those who are deficient. However, knowing the signs can allow for early prevention of conditions, which, if left unchecked, could lead to nerve damage.
MedlinePlus describes the following as symptoms of vitamin B-12 deficiency:
- Diarrhea or constipation
- Fatigue, excessive tiredness, or feeling light-headed when standing up or when exerting energy
- Reduced desire to eat or complete loss of appetite
- Change in skin color, paleness
- Feeling persistently irritated or easily agitated
- Shortness of breath, predominantly during exercise or while performing any activity that requires unusual exertion
- Tongue swelling or bleeding gums
If any of the above symptoms seem familiar or you notice them in yourself or others, contact your healthcare professional for further advice.
Causes of Vitamin B-12 Deficiency
According to MedlinePlus, vitamin B-12 is found in meat, poultry, shellfish, eggs, fortified cereals and dairy products. Therefore, if your regular diet excludes any or all of these foods, you may be putting yourself at risk of a vitamin B-12 deficiency.
For this reason, many vegetarians and vegans are often at risk of a vitamin B-12 deficiency because they do not consume meat, fish, eggs, cheese and milk. The National Health Service also explains that vitamin B-12 is not found in fruit, vegetables and grains at all, so vegans, in particular, must take extra caution.
The National Health Service also says that the daily recommended amount of vitamin B-12 that people should consume is approximately 1.5 micrograms per day. If meat, fish and dairy products are a part of your usual diet, you should be getting this amount of vitamin B-12 solely from food consumption.
Taking Vitamin B-12 Before Bed
If you do require additional vitamin B-12 because you don't get enough from your diet alone, there are many supplements available in various forms. Vitamin B-12 is found in almost all multivitamin supplements, so it can be taken among other vitamins.
There is no specific time of day recommended when you should take vitamin B-12 supplements, as there is no clinical evidence demonstrating a significant difference between taking vitamin B-12 in the morning or at night. For this reason, it is entirely up to you and your personal schedule to decide when is the best time to take it. Some take it with their breakfast, others just before bed — whatever works for each individual.
Read more: Vitamin B12 Disadvantages
Vitamin B-12 and Sleep
The link between vitamin B-12 and sleep is not particularly clear. An August 2014 study published in PLoS One found that there was a negative correlation between vitamin B-12 intake and sleep duration, and concluded a further longitudinal study would need to take place before any concrete conclusions could be made.
However, taking vitamin B-12 right before bed can potentially have a negative effect on sleep because of extraneous factors. For instance, the Mayo Clinic advises that higher doses of vitamin B-12 used to treat a deficiency can cause any of the following side effects:
None of the above are ideal when you're trying to get a good night's rest, but it is also important to bear in mind that these side effects are unlikely and may not occur — so you can try taking the supplement at night and see what happens.
Vitamin B-12 and Energy
It's also important to consider that vitamin B-12 is integral to the release of energy in the body, which is why a deficiency can cause tiredness. Because of its role in increased energy, it may affect your body's ability to rest — so if you experience any sleep disruptions following a nighttime dose of a vitamin B-12 supplement, it may be wise to switch to taking it in the morning instead.
Though vitamin B-12 is important with regard to energy metabolism, there is no clinical evidence to suggest it can be used as an athletic performance enhancer.
What Is Mecobalamin?
Mecobalamin is a form of vitamin B-12, also known as methylcobalamin. It is the activated form of vitamin B-12 and has been used to treat a variety of nutritional diseases as well as conditions such as Alzheimer's and rheumatoid arthritis.
A December 2013 study published in the Journal of Neural Plasticity found that mecobalamin (referred to as methylcobalamin and vitamin B-12 alike in the publication) actually acted as a painkiller in certain areas of the body when administered, particularly in nonspecific areas of low back pain, neck pain and diabetic neuropathic pain.
A January 2017 study published in the Journal of Pharmacology and Pharmacotherapeutics explored the difference in the effectiveness of administering mecobalamin to treat vitamin B-12 deficiency and the subsequent reactions caused when it interacted with other nutrients in the body and found that the administering of mecobalamin alone did not work to reverse any neurological deficit caused by deficiency. The study concluded that further clinical trials would need to take place.
Read more: Problems Absorbing Vitamin B12
Vitamin B-12: Morning or Night?
The clinical evidence available demonstrates no significant indicator of the best time of day for vitamin B-12 supplementation.
Though there is a case to be made that nighttime consumption could potentially disrupt sleep, there is no proven evidence to display a direct correlation between the two. So unless sleep disruption is a persistent symptom after you take vitamin B-12, taking it at bedtime should be fine.
Should you require vitamin B-12 supplementation, take it when it is most convenient to your personal schedule, morning or night.
- National Institutes of Health: "Vitamin B12"
- MedlinePlus: "Vitamin B12 Deficiency Anemia"
- National Health Service: "B Vitamins and Folic Acid"
- Mayo Clinic: "VItamin B12"
- National Institutes of Health: "Vitamin B12: Healthcare Professionals"
- National Library of Medicine: "Methylcobalamin: A Potential Vitamin of Pain Killer"
- National Library of Medicine: "Methylcobalamin in Vitamin B12 Deficiency: To Give or not to Give?"
- PLoS ONE: "Serum Nutritional Biomarkers and Their Associations With Sleep Among US Adults in Recent National Surveys"