When taken at appropriate doses, vitamin B-12 supplements are generally considered safe. While the recommended daily amount of vitamin B-12 for adults is 2.4 micrograms, higher doses have been found to be safe. Your body absorbs only as much as it needs, and any excess passes through your urine.
If you are low in vitamin B12, a common recommended dose for oral supplements is about 1,000 mcg daily. But you should make sure to ask your healthcare provider about how much vitamin B12 you should look for in a supplement.
Supplementation of 25-100 mcg per day has been used to maintain vitamin B12 levels in older people. For vitamin B12 deficiency: Vitamin B12 doses of 300-10,000 mcg daily have been used. However, some evidence suggests that the most effective oral dose is between 647-1032 mcg daily.
A few people experience gastrointestinal issues, such as bloating or diarrhea, from getting too much B-12. In rare cases, too much B-12 from a combination of diet and supplements can cause blood clots. You could also be allergic to a B-12 supplement and experience itching and rashes.
As summarized in the table provided, vitamin B12 (cobalamin) absorption and utilization by the body can be compromised with the chronic use of certain medications which include: colchicine, chloramphenicol, ethanol, histamine 2 receptor antagonists (H2RA), metformin, and proton pump inhibitors (PPI).
Recommended Vitamin B12 Dosage for Seniors
A recent study found that for seniors, a daily dose of 500 micrograms was efficient in reversing the signs of B12 deficiency. In general, experts recommend 2.5 micrograms of vitamin B12 per day for people over the age of 14.
While megadoses of up to 2,000 mcg are considered safe in treating B12 deficiency, it's always best to avoid excessive amounts of any vitamin, especially when it's not needed.
There is no risk of an overdose when taking large amounts of vitamin B-12 such as 1000 mcg, because it is a water-soluble vitamin. Meaning the body will use the amount that it needs then the excess will be excreted through urine.
diet-related deficiency is 50 micrograms to 150 micrograms, taken once a day. B12 deficiency not caused by your diet is one to two 1,000 microgram tablets, taken once or twice a day – this is usually if you cannot have vitamin B12 injections.
A: 2.4mcg is only approximately 1/250th of 1000mcg.
Extra strength B-12 supplements offer this amount—3,000 mcg—in one serving. If you think 125,000% seems excessive, you may be right (NIH-a, 2021). Fortunately, even at large doses, vitamin B12 is generally considered safe, at least in the short term (more on that below).
The Institute of Medicine's Food and Nutrition Board recommends that healthy adult men and women over 19 years old consume 2.4 micrograms of vitamin B-12 each day. Pregnant women need 2.6 micrograms daily and women who are breastfeeding need 2.8 micrograms daily.
Methylcobalamin. Methylcobalamin is the most bio-available type of Vitamin B12 which means the body absorbs it more easily. Naturally occurring, it is found in animal-based foods such as meat, fish, milk and eggs so Methylcobalamin B12 is readily available in many people's daily diets.
Vitamin B12
As a general rule of thumb, take your B vitamins in the morning or with a meal. Vitamin B12, for example, should definitely be taken in the morning. This is because it is important for energy metabolism, which may interrupt your sleep if taken at night.
How Long Does It Take for Vitamin B12 to Work? It can take 3-4 weeks to start feeling better after taking vitamin B12 consistently. However, it can take six months or more to recover from a severe B12 deficiency. One of the most common reasons people take B12 is to boost their energy levels.
Vitamin B12 is an essential nutrient. Fish, shellfish, meat, eggs, and dairy products are good sources of vitamin B12. The amount that should be consumed on a daily basis is called the recommended dietary allowance (RDA). The RDA is 2.4 mcg daily for people 18 years and older.
Stores of vitamin B12 in the body can last around 2 to 4 years without being replenished, so it can take a long time for any problems to develop after a dietary change.
Disturbed or blurred vision can also occur as a result of a Vitamin B12 deficiency. This happens when the deficiency causes damage to the optic nerve that leads to your eyes. The nervous signal that travels from the eye to the brain is disturbed due to this damage, leading to impaired vision.
Lack of vitamin B12 in your diet: People who don't eat enough foods that naturally have vitamin B12 or don't eat foods fortified with vitamin B12 can develop vitamin B12 deficiency. Gastritis: Gastritis is inflammation of the stomach lining, and it's a common cause of vitamin B12 deficiency.
If you are an older adult, you should be taking a supplement for B12 as well as trying to incorporate B12 into your diet. It is vital for good health and cognitive functioning. Studies continue to show all the ways it is beneficial for your overall health.
With that in mind, let's go back to our initial question: how much vitamin B12 should a person over 65 take? Recent reports suggest that, along with a B12-rich diet, consuming 500 micrograms of B12 in the form of a supplement may help individuals over 65 maintain healthy vitamin B12 levels [2].
B-Methylated-II is an excellent option for seniors who may have difficulty swallowing pills, and also have greater needs for folate and B12. Methylfolate and B12 are crucial cofactors in one-carbon metabolism and are both required for the breakdown of homocysteine and in neurological health.
Doctors tend to prescribe these higher dosages to treat conditions related to very low vitamin B-12 levels, such as pernicious anemia. Although vitamin B-12 appears, for the most part, to be safe — even at higher dosages — more is not necessarily better. There is no need to take very high doses of vitamin B-12.
Maintain gut health
Boosting cobalt supplies and fortified meals is essential, but so is increasing absorption power. This is where gut health comes into play since it is important for proper vitamin and nutrient absorption. Vitamin B12 gets absorbed in the stomach, thanks to a protein known as intrinsic factor.