Most healthy, meat-eating people will get enough vitamin B12 from their normal diets, but there are still millions of people around the world who would benefit from boosting their nutritional intake with a B12 supplement. These are available in a wide variety of forms, including not only the standard oral tablets, but also skin patches, injections, sprays, intranasal gels and sublingual tablets (which are placed under the tongue). But are you likely to need any of these in the first place?
Natural Sources of Vitamin B12
B12 is generally only found in animal products, with the richest sources being beef products and fish such as trout, salmon and tuna, although all of these pale in comparison to both liver and seafood like clams, oysters and crabs. These are all packed with high levels of vitamin B12, and they’re generally pretty healthy in most other respects as well.
Eggs, cheeses and yogurts all contain good amounts of B12 too, as does whole milk.
Plants are a different story, as they won’t normally contain vitamin B12. This means that aside from animal-based foodstuffs, there are very few natural sources of B12 for you to make use of.
Who is Most Likely to Need a Supplement?
Vegetarians may well struggle to get enough vitamin B12 from natural sources, and vegans even more so. Most vegan societies recommend that all vegans use commercially available supplements to increase their intake to recommended levels, and many vegetarians find it necessary as well.
Another group of people who run a higher risk of vitamin B12 deficiency are the elderly. It’s estimated that as many as 20-30% of over-50s may be at risk due to a condition known as atrophic gastritis, which basically means that the afflicted individual isn’t able to properly digest and process certain key nutrients, including vitamin B12.
People with atrophic gastritis were given B12 injections in the past in order to bypass the normal method of absorption in the gut, but recently the trend has shifted. Now most patients are instructed to simply take oral supplements in high doses (perhaps as high as 1mg).
It has been found that even patients who cannot absorb adequate B12 from their food can absorb enough from these high concentrations. (This is achieved by passive diffusion in the intestine.) Tablets like these are ideal if you’re in this situation (and will also work well for general supplementation).
High levels of vitamin B12 in the blood will also reduce the amount of homocysteine, which is particularly important for the elderly. This is because high levels of homocysteine are associated with a greater chance of getting Alzheimer’s disease or suffering from excessive brain shrinkage in old age.
Claims that taking oral contraceptives increase your chances of suffering from B12 deficiency are false. You can find out more here if you’re interested.
Pre-existing Conditions That Reduce B12 Levels
If you suffer from celiac disease, Crohn’s disease or any other condition affecting the small bowel you should also take steps to ensure that your body is getting enough B12, as the affected area is where most absorption of the vitamin occurs. Injections may sometimes be necessary.
Diabetics who use the medication metformin also suffer from an impaired ability to absorb B12 and should talk to their doctor about this potential problem as soon as possible.
There are many more risk factors, but all are fairly uncommon. They include a variety of hereditary causes, abuse of nitrous oxide, various prescription medications, parasitic infections of the gastrointestinal tract, and more. If any of these apply to you, it’s important that you consult your doctor about supplementing your vitamin B12 intake.
Alternatives to Supplements
If you decide that you want or need to supplement your diet with extra vitamin B12 but don’t fancy taking it directly in its pure form, the only real option is to try foods that have been fortified with B12. There aren’t a huge number of these available, although fortified porridge oats, granola and protein/energy bars are probably the most popular of the options on offer.
Should I Take a Vitamin B12 Supplement?
Ultimately the decision is yours to make, but note that vitamin B12 has extremely low levels of toxicity. Various studies have put human test subjects on doses of B12 far above the recommended daily amounts for long periods of time, sometimes even for several years. None of these studies have suggested that large quantities of this vitamin are in any way harmful. Yet if your body doesn’t get enough B12 for whatever reason, you’re likely to end up with vitamin B12 deficiency, which is definitely something you don’t want to happen.
This means that you shouldn’t worry about accidentally taking too much B12, as this is a problem that doesn’t really exist, whereas at the other end of the spectrum, a deficiency can be extremely serious. So if you’re vegetarian or vegan or suffer from any of the ailments listed above, or are just concerned that you might not be getting enough for any other reason, it’s probably worth taking a supplement.
However, you should consult a healthcare professional first if you have any serious underlying conditions such as diabetes or Crohn’s disease.
If you do choose to take a supplement, we recommend that you check that the B12 included is in the methylcobalamin form, which is more bioavailable and has a range of benefits over the inferior cyanocobalamin form more commonly used in supplements. You can read more about the differences between them here and see our recommended methylcobalamin-containing B12 supplements here.
From top to bottom, images are courtesy of Kittikun Atsawintarangkul, graur razvan ionut, YaiSirichai and jscreationzs, all at FreeDigitalPhotos.net