Is 1000 mcg the same as 2.4 mcg?
1000 mcg is about 400 times as much as 2.4 mcg. However, the B12 molecule is too large to cross from the gut to the blood unaided. It needs to be carried across the gut wall by a special protein called Intrinsic Factor. And that mechanism has a limited capacity.
In a 2013 study in 100 older adults, supplementing with 500 mcg of vitamin B12 for 8 weeks was found to normalize B12 levels in 90% of participants. Higher doses of up to 1,000 mcg, or 1 milligram (mg), may be necessary for some ( 13 ).
It's common to start treatment for a significant vitamin B12 deficiency with weekly intramuscular shots (1000 micrograms of vitamin B12). This bypasses any absorption problems in the stomach or intestine, and is a good way to get an older person's vitamin B12 level back to normal quickly.
For example, absorption is only about 2% at doses of 500 mcg and 1.3% at doses of 1,000 mcg [25]. In addition to oral dietary supplements, vitamin B12 is available in sublingual preparations as tablets or lozenges [23].
Even the lowest doses in B12 supplements are many times the recommended dietary allowance. Doses up to 1,000 mcg, though unnecessary, aren't harmful. Fortified foods. Many breakfast cereals, soy products, and yeasts are fortified with B12.
B12 is important for many enzymatic processes, such as helping turn the food you eat into usable energy. The recommended daily amount for B12 is 2.4 mcg for adults. Pregnant and lactating women need higher amounts [1]. There is no upper intake limit for vitamin B12 because there is no known toxicity [2].
2.4mg would translate to 2400 MICROgrams (mcg) and is a common and acceptable dosage. 1500 MILLIgrams (mg) translates as 1,500,000 MICROgrams (mcg) and is an obvious overdose. 1 mg = 1000 mcg. Don't believe everything you see on the internet.
Dosages for Older People
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.
The amount of vitamin B12 that seniors should take depends on the level of need a given senior has; that's why it's important to involve medical professionals. In general, the recommended daily allowance is 2.4 mcg.
A blood test showing a serum vitamin B12 level between 300 and 350 pg/mL is ideal for seniors, while anything between 200 and 900 pg/mL is considered normal. An elderly person should be getting 2.5 micrograms of B12 per day.
How long does it take for B12 1000 mcg to work?
B12 injections work quickly and typically show noticeable effects within 48 to 72 hours. These effects may include better moods, more energy, less fatigue, and a general sense of wellbeing. If you have a mild deficiency, it may take two to three shots over several days or weeks before you begin feeling a difference.
One large study found that women who took 1,000 mcg of vitamin B12, along with 2500 mcg of folic acid and 500 mg of vitamin B6 daily, reduced the risk of developing AMD, an eye disease that can cause loss of vision.
A B12 ≥ 1000 ng/L was associated with the presence of solid cancer without metastases (OR 1.96 [95%CI: 1.18 to 3.25]) and with metastases (OR 4.21 [95%CI: 2.67 to 6.64]) after adjustment for all elevated B12-related causes.
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].
In diabetes patients with advanced kidney disease, high daily doses of B vitamins (folate, B6 and B12) were found in one study to worsen kidney function and double the risk of heart attack stroke and death (see the Cautions section of the B Vitamins Review for more information).
Left untreated, a vitamin B-12 deficiency can lead to anemia, fatigue, muscle weakness, intestinal problems, nerve damage and mood disturbances. The recommended daily amount of vitamin B-12 for adults is 2.4 micrograms.
This is particularly important if you experience any symptoms of high B12 levels in blood, including [9]: Gastrointestinal issues (like nausea, vomiting, and/or diarrhea) Headaches. Tingling in your hands and feet.
Since B12 is a water-soluble vitamin, it's generally considered safe, even at high doses. No Tolerable Upper Intake Level (UL) has been established for B12, due to its low level of toxicity.
Therefore, 2.4 mcg is equivalent to 0.0024 times the content of a 1000 mcg container.
Top foods with B12
The average adult should get 2.4 micrograms (mcg) of vitamin B12 a day, according to the National Institutes of Health. Here are some of the best foods with B12: Clams, 3 ounces: 84 mcg. 100% fortified breakfast cereal (check the label), 1 serving: 6.
How many mcg of B12 is enough?
Animal products such as meat, dairy and eggs are the only sources of B12 in humans, and the recommended daily allowance is 2.4 micrograms per day. The average intake of an individual in the United States is approximately 3.4 micrograms per day, but if you follow a vegan diet, you obviously lack sources of B12.
The usual dose for: 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.
We highly recommend Nature Made Vitamin B12 1000 mcg Softgels for seniors looking for a high-quality B12 supplement to support energy metabolism and overall health. These softgels help break down food into energy that your body can use all day long.
You can swallow a pill or take a tablet that melts under your tongue. The doctor may start you out at 1,000-2,000 micrograms a day. Once your levels are normal, you may need 100-500 micrograms a day or 1,000 micrograms one or two times a week.
Interactions between your drugs. No interactions were found between Vitamin B12 and Vitamin D3. However, this does not necessarily mean no interactions exist. Always consult your healthcare provider.
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