Is 1000 mg of b12 too much
Emma Miller
Updated on April 02, 2026
In one 8-week study in 100 older adults, supplementing with 500 mcg of vitamin B12 were found to normalize B12 levels in 90% of participants. Higher doses of up to 1,000 mcg (1 mg) may be necessary for some ( 10 ).
Is it OK to take 1000 mcg of B12 a day?
The recommended dose for treating vitamin B12 deficiency is 1000 mcg daily. The recommended dose for preventing vitamin B12 deficiency is 1500 mg or 2500 mcg (sublingual tablets) daily. The dose for treating hyperhomocysteinemia is 400 mg daily in combination with folic acid.
Is 1000 mcg of B12 safe for seniors?
Recommended Vitamin B12 Dosage for Seniors The proper vitamin B12 dosage for seniors depends on if they have underlying health conditions and how severe their deficiency is. In some cases, doctors may recommend high doses — more than 1,000 micrograms (mcg) per day.
Is B12 level of 1000 too high?
There is no consensus on the definition of high or elevated B12. Previous studies have chosen a variety of levels to represent high or very high B12 (pmol/l) levels. Some examples include: 664.219; 5131; 700 (high) and 1500 (very high)11; and 601 (high) and 1000 (very high)10.How much B12 is considered high?
High. An abnormally high vitamin B-12 status is anything over 900 pg/mL. This result may suggest liver or kidney problems, diabetes, or certain forms of leukemia.
Can you overdose on B12?
No, you cannot overdose on B12 Medical term: A tolerable upper intake level is the highest level of nutrient intake that does not pose any adverse health effects for the majority of people. Vitamin B12 is a water-soluble vitamin, meaning it dissolves in water and is quickly absorbed by the body.
What is the difference between 2.4 mcg and 1000 mcg?
2.4mcg is only approximately 1/250th of 1000mcg.
Is High B12 worrisome?
Elevated levels of serum cobalamin may be a sign of a serious, even life-threatening, disease. Hematologic disorders like chronic myelogeneous leukemia, promyelocytic leukemia, polycythemia vera and also the hypereosinophilic syndrome can result in elevated levels of cobalamin.Is 1100 B12 level too high?
The normal range for vitamin B12 (total) is between 200 – 1100 ng/L (nanograms per liter), 200 – 1100 pg/mL (picograms per milliliter), or 148 – 811 pmol/L (picomoles per liter). The normal range for active vitamin B12 (holoTC) is around 20 – 134 pmol/L (picomoles per liter).
Can B12 hurt your liver?The common forms of vitamin B include vitamin B1 (thiamine), B2 (riboflavin), B3 (niacin), B6 (pyridoxine) and B12 (cyanocobalamin). Except for niacin (when given in high doses), there is no evidence that the other B vitamins, in physiologic or even super-physiologic high doses cause liver injury or jaundice.
Article first time published onHow much B12 should a 60 year old woman take?
When you’re in your 60s you should officially start getting blood tests to test for vitamin B12 deficiency. Around this age, you should be getting around 2.4 micrograms of B12 a day.
What medications should not be taken with B12?
Certain medications can decrease the absorption of vitamin B12, including: colchicine, metformin, extended-release potassium products, antibiotics (such as gentamicin, neomycin, tobramycin), anti-seizure medications (such as phenobarbital, phenytoin, primidone), medications to treat heartburn (such as H2 blockers …
How much vitamin B12 should a woman over 50 take?
The latest guidelines recommend 2.4 micrograms per day of vitamin B12 for those aged 51 and older. Most daily multiple vitamins supply this amount.
Is 500 a good B12 level?
The vitamin B12 standard reference range is 200–700 pg/ml whereas the proposed optimal range is 500–1300 pg/ml [10]. Higher vitamin B12 ranges have been associated with increased cognitive function, and reflexes, decreased brain atrophy, confusion, weakness and depression [10].
How much B12 do I need daily?
Safety and side effects. 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 …
What does 1000 mcg stand for?
Mcg is microgram…. 1,000,000th of a gram. mg milligram is 1000th of a gram. 1000 mcg = 1 mg. … One milligram, abbreviated as mg, equals 1,000 micrograms, abbreviated as mcg, µg or ug.
Is 1000 mcg more than 2.4 mcg?
1000 mcg is about 400 times as much as 2.4 mcg.
Can B12 cause anxiety?
B12 Causes Psychiatric Symptoms: B12 deficiency can cause almost any psychiatric symptom, from anxiety, and panic to depression and hallucinations. This is because B12 deficiencies trigger symptoms in the nervous system and red blood cells.
What causes too much B12 in the blood?
The most common cause of high B12 in the blood is due to recent ingestion or injection of supplemental vitamin B12. We don’t worry about overdosing on B12 supplements because excess can be excreted in your urine. It could also be possibly from your diet if high in animal products such as meat, eggs, and shellfish.
Can vitamin B12 cause high blood pressure?
Vitamin B12 was significantly associated with blood pressure when folic acid intake was high and vice versa. Considering that folic acid and vitamin B12 act together as cofactors in converting homocysteine into methionine,6 folic acid, and vitamin B12 may have synergic effects on blood pressure or endothelial function.
How long does it take to get rid of excess B12?
Unlike most other vitamins, B12 is stored in substantial amounts, mainly in the liver, until it is needed by the body. If a person stops consuming the vitamin, the body’s stores of this vitamin usually take about 3 to 5 years to exhaust.
What are the neurological symptoms of B12 deficiency?
- vision problems.
- memory loss.
- pins and needles (paraesthesia)
- loss of physical co-ordination (ataxia), which can affect your whole body and cause difficulty speaking or walking.
Is B12 hard on kidneys?
A: Vitamin B-12 is a water-soluble vitamin. Excess amounts of it (no matter how much you take) typically are just cleared by the kidney, so high levels of B-12 can occur if the kidneys aren’t working properly. B-12 is stored by the liver, so any liver damage that causes cells to die can increase blood B-12 levels.
Can B12 cause blood clots?
Population research suggests that having low levels of vitamin B12 might be linked to an increased risk for blood clots in the veins.
Can u overdose on vitamin B?
You’re also unlikely to get too much vitamin B if you’re taking any supplementation as directed. That said, overdose is possible — especially if you’re taking a supplement without receiving a deficiency diagnosis from your doctor. Symptoms of a vitamin B complex overdose include: excessive thirst.
What is Vitamin B12 1000 mcg used for?
Cyanocobalamin is a man-made form of vitamin B12 used to treat low levels (deficiency) of this vitamin. Vitamin B12 helps your body use fat and carbohydrates for energy and make new protein. It is also important for normal blood, cells, and nerves.
Is vitamin B12 good for arthritis?
Vitamin B complex is a type of non-antioxidant vitamin. We don’t fully understand how this type of vitamin may treat arthritis-related conditions, but evidence from trials suggests that vitamins B3, B9 and B12 might be of some benefit for treating osteoarthritis, particularly in improving joint mobility and hand grip.
Can vitamin B12 and vitamin D3 be taken together?
No interactions were found between Vitamin B12 and Vitamin D3. This does not necessarily mean no interactions exist. Always consult your healthcare provider.
How much B12 does a female need daily?
The typical general supplemental dose of vitamin B12 is 1-25 mcg per day: The recommended dietary allowances (RDAs) of vitamin B12 are: 1.8 mcg; older children and adults, 2.4 mcg; pregnant women, 2.6 mcg; and breast-feeding women, 2.8 mcg.
Is 350 a good B12 level?
A serum vitamin B12 level between 200 pg/mL and 900 pg/mL is considered normal, but a threshold of 300 to 350 pg/mL is recognized as a marker for a desirable status in the elderly. The laboratory diagnosis is usually based on low serum vitamin B12 levels or elevated serum methylmalonic acid and homocysteine levels.
Which is the best vitamin B12 to take?
- Jarrow Formulas Methyl B12 Chewable – 60 count.
- Vitafusion Vitamin B12 Gummy – 140 count.
- Solimo Vitamin B12 Gummy – 100 count.
- Doctor’s Best Fully Active B12 Capsule – 60 count.
- MaryRuth’s Methyl B12 Organic Liquid Spray – 1 fluid ounce.