Answer: If your B-complex contains 50,000% of the Daily Value (DV), which is 6 mcg for adults, then it has 3,000 mcg of B-12. For people without a severe B-12 deficiency, this is certainly more than necessary. Taking some B-12 is advisable for people over the age of 50 (when you're less able to extract B-12 from food), as well as for those taking medications that interfere with B-12 absorption, strict vegetarians, alcohol and drug abusers, people recovering from surgery or burns, and those with bowel or pancreatic cancer. Although vitamin B-12 is generally considered to be safe, and no "Upper Tolerable Intake Level" has been established, there are some reports of doses of 20 mcg per day or higher causing outbreaks of acne and rosacea. There is also a study which showed that a high-dose B complex supplement (with 1,000 mcg of B-12) hurt, rather than helped, people with type 1 or type 2 diabetes and advanced kidney disease, resulting in a worsening of kidney function and an increase in the risk of heart attack, stroke and death.
Be aware that sublingual and dissolvable B-12 supplements often contain sugar substitutes which can, in some people, cause gas, bloating, and diarrhea -- particularly if taking multiple pills. In women who are pregnant, excessive blood levels of vitamin B-12 have been associated with an increased risk of autism in their children. In general, it's best to avoid excessive doses of any vitamin if it is not needed. 's tests of popular products, in the B Vitamin Supplements Review >> You can check the recommended intakes of other vitamins and minerals here. Also see the CL Answer "Can taking too much vitamin B-6 be dangerous?"It is always explicitly recommended that Vitamin B12 tablets should be dissolved under the tongue (aka “sublingual”). I wonder if that is also true for other minerals and vitamins of special concern to vegetarians, such as iron and vitamin D2? If not, why is this the case with vitamin B12? I have always told people who asked about sublingual B12 that there was no evidence, of which I was aware, that sublingual was any better than just chewing.
Despite this, until today, I had been recommending sublingual in my Step 1 Recommendations, which are geared towards people who have not recently had a reliable source of B12. I have recommended sublingual as a precaution just in case it was more effective. In recent years, I have been more diligent about trying not to recommend anything just to be prudent unless specifically stating that is why I am recommending it. This suggestion for sublingual (versus just oral) was a remnant left over from previous times. Still, I did not know whether sublingual was better than oral until I got this question and decided to check in on the research. As it turned out, there was a study as long ago as 2003. I guess I hadn’t checked in quite a long time. The 2003 study compared 500 µg per day via the sublingual and oral routes. The results were that sublingual was absolutely no better than oral B12 at raising vitamin B12 levels or improving B12 activity (as measured by homocysteine and methylmalonic acid levels).
The report did not specifically state whether the tablets were chewed or not (I assume that they were swallowed whole). So now I’m not sure I should even suggest that the tablets be chewed, but because other studies have shown a benefit to chewing, I will leave that in my recommendations. As for other vitamins and minerals, I have never checked into the research on taking them via the sublingual route, but my sense is that there would not be any benefit. It might even be dangerous to try this with iron given that it is a pro-oxidant and probably should not be held in constant contact with your tissues. Sharabi A, Cohen E, Sulkes J, Garty M. Replacement therapy for vitamin B12 deficiency: comparison between the sublingual and oral route. Br J Clin Pharmacol. This entry was posted on Friday, April 6th, 2012 at 5:31 pm and is filed under Supplements, Vitamin B12. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response.
Pinging is currently not allowed.Recently, vitamin B12 has been linked to weight loss and energy boosts, but are these claims for real? A lot of doctors and nutritionists lean toward "no." Vitamin B12 plays a major role in a number of the body's essential functions, including DNA synthesis and the formation of red bloodVitamin B12 also helps the body convert fats and proteins into energy. B12 deficiency can lead to several ailments, most notably megaloblastic anemia, which is caused by a low red blood cell count. common symptom of megaloblastic anemia is fatigue. This form of anemia — as well as other health issues associated with B12 deficiency — can be easily treated with injections of the vitamin. Claims that B12 can boost energy and aid in weight loss come from the incorrect assumption that the effect it has on people with megaloblastic anemia will be the same in people with normal levels Most people get vitamin B12 through their food.
is naturally present in certain animal protein-based foods, such as: Since B12 is only found naturally in these animal products, deficiency is common among vegetarians and vegans if they do not consume fortified foods such as fortified cereals and fortified yeast. Other groups of people at risk for B12 deficiency include the elderly, people who are HIV positive, people who have undergone gastrointestinal surgery, and people with certain digestive disorders, specifically Crohn's disease and celiac disease. Celiac disease is the autoimmune disorder thatElderly people or those who have undergone stomach surgery generally have lower levels of acid in the stomach, which can result in reduced absorption of B12 from animal foods. For these people, B12 found in fortified foods or supplements might be a better option. Also, people who take the diabetes drug metformin are at higher risk for B12 deficiency. There are many ways for people at risk for B12 deficiency to
add more to their diet. Like just about any vitamin and mineral on the market, B12 supplement pills are available at supermarkets and pharmacies. present in B complex supplements, which combine all eight of the B vitamins into a single dose. You can get larger doses of B12 through an injection, which is a common way weight loss facilities administer the supplement. typically suggest injections of higher-than-average doses of B12 for people diagnosed with megaloblastic anemia and other health problems associated with a B12This type of injection often requires a doctor's prescription. Foods where the vitamin is not naturally present – such as breakfast cereals – can also be "fortified" with B12. useful for people at risk for deficiency. Check the nutritional information on food labels to see if it’s been fortified. Institutes of Health (NIH) recommend 2.4 micrograms (mcg) of vitamin B12 per day for anyone over the age of 14.