Most of us don’t need supplements
Save your money.
I spent some time this weekend researching vitamin B12 deficiency and the need for supplements. An elderly relative has been experiencing months of fatigue and wonders if a B12 supplement might help her.
Despite all the products you can buy that contain vitamin B12 to “boost” energy levels or “support” memory, most of us aren’t low in vitamin B12 and won’t benefit from supplements.
At worst, too much extra B12 can actually be harmful!
The recommended dietary allowance (RDA) of B12 for adults is quite small—only 2.4 micrograms. We get many times that amount if we eat a typical, healthy diet. The top foods for B12 are shellfish, liver, fish, red meat, eggs, dairy, and fortified breakfast cereals.
For example, a glass of milk has about 50% of the RDA. A cup of fortified bran flakes has 250% of the RDA. A 6-oz steak will have more than 500% of the RDA. Over a day, it’s not difficult to get the recommended amount, even if you don’t eat liver (and who does?).
Related post: Healthy adults don’t need multivitamins
We don’t absorb everything we eat, however. There’s a protein made in our stomachs called “intrinsic factor” and it helps our intestines absorb B12. It’s estimated that our intrinisic factor maxes out at 1.5 micrograms over a 4-6 hour period; it doesn’t help to load up on high-B12 foods in one meal.
B12 is one of the water-soluble vitamins, so most of the extra we take in is just peed out. The body stores a small amount. It can take years to become deficient in B12, which is one of the reasons it’s uncommon.
The Centers for Disease Control (CDC) estimates only 2% of Americans suffer from low B12 levels.
Who benefits from extra vitamin B12?
Although most of us don’t need supplements, there are some people who are at higher risk of developing a vitamin B12 deficiency.
- The elderly (like my relative). As we age, our stomachs produce less stomach acid (which separates B12 from food) and intrinsic factor. Our intestines also don’t absorb nutrients as well, either.
- Vegetarians and vegans. Meat is a major source of B12, so anyone with a meatless diet, and especially a dairy-free diet, has to be very conscientious about getting enough. Fortified cereals, tofu and nutritional yeast are good sources.
- People with intestinal problems. Anyone with conditions like Crohn’s disease, ulcerative colitis or celiac disease doesn’t absorb nutrients well. Also anyone taking antacids long-term for heartburn or gastroesophageal reflux (GERD) may have a problem because their stomachs stop making enough stomach acid. That’s another good reason not to treat yourself with OTC Nexium for more than 2 weeks! (Read more about that in my post on the topic.)
My relative is over 80, so the chance she is vitamin B12 deficient is fairly good. Otherwise she’s in pretty good health and will see her doctor in a couple of months. She could get a blood test to check her vitamin B12 level, but it’s not all that useful. Many seniors have fatigue or other symptoms, even though the blood test is normal.
Taking a low-dose supplement (500 micrograms) is safe and inexpensive. She should know within a month or two if it is helping or not. If not, she can follow up with her physician.
Supplements for vitamin B12 deficiency
If you’re always tired and not sure why, talk to your doctor. Even though fatigue is a symptom of B12 deficiency, many other things can cause low energy levels. Your primary care physician is the best person to help sort it out.
The blog Science-Based Pharmacy has a good post about the marketing hype behind vitamin B12. B12 supplements won’t provide an “instant” energy boost. It takes time to become deficient, and it takes time to build up vitamin B12 in your system again. Any instant energy spike you experience is more likely from added sugar or caffeine.
So if you’re really, truly B12 deficient, go for a quality supplement rather than gummi vitamins or energy drinks or any other product that makes too-good-to-be-true claims.
According to the independent supplement review group, ConsumerLab (requires a subscription), a 500 or 1000 microgram supplement is sufficient for almost everyone with a B12 deficiency. Higher doses should be supervised by a physician.
Most supplements are over 1000 micrograms because only about 1% of the dose is absorbed through the intestine. Unlike food, supplements don’t require intrinsic factor.
There are many forms of B12 supplements: tablets, sprays, drops, dissolving lozenges, and gummies. ConsumerLab says plain tablets are absorbed as well as the other forms, are usually cheaper, and don’t have added ingredients like artificial sweeteners.
I always recommend choosing a reputable brand with the lowest price point. I chose Nature Made 500 mcg tablets for my relative.
If you want more information about supplements and supplement safety, I have a list of good websites on my Resources page.
And if you take a lot of supplements, or like using herbal remedies, I highly recommend getting a subscription to ConsumerLab. Like Consumer Reports (not related) it reviews the research and tests and rates products for purity and price. A subscription costs about $50 for 12 months.