Takeaway: Regardless of the dietary plan you follow, getting a sufficient amount of B12 is not only possible but also essential to your health. Because diagnosing a B12 deficiency can be relatively difficult, it is a good idea to ensure you are eating B12-rich foods or using a B12 supplement—preferably one that you’ve done your research on—to avoid a deficiency.
There’s no question that vitamin B12 is essential for good health. However, despite that, vitamin B12 deficiency is still common among many people. In this article, we cover the different symptoms, benefits, and types of supplements associated with vitamin B12.
Who Needs B12 Supplements?
A Tottori University research study conducted by the Graduate School of Agricultural Sciences found that B12 deficiencies are prevalent among the elderly and people who follow a vegetarian diet. This is because unlike some other B vitamins, vitamin B12 is not found in any plant food other than fortified cereals. It is, however, abundant in many types of meat and fish, and in smaller amounts in milk and eggs. Avoiding these foods makes it difficult for people following a strict vegetarian diet to get the necessary amount of vitamin B12.
Other people that would benefit from vitamin B12 supplements are:
- Those who’ve had surgery that removes the part of the bowel that absorbs B12
- People on the drug metformin for diabetes
- Those taking long-term antacid drugs for heartburn
- People who suffer from anemia
In addition, some people make take vitamin B12 supplements to:
- Prevent memory loss
- Prevent Alzheimer’s disease
- Slow aging
- Boost mood, energy, concentration, mental function, and the immune system.
- Prevent heart disease, clogged arteries and decreasing the risk of re-clogging arteries after surgery.
- Reduce high triglyceride levels
- Lower high homocysteine levels (which may contribute to heart disease)
- Prevent diabetes and diabetic nerve damage
- Treat depression and some mental disorders
- Prevent osteoporosis
- Treat asthma, allergies, a skin disease called vitiligo, and skin infections.
A vitamin B12 deficiency is a condition that occurs when vitamin B12 levels in the blood are extremely low. A B12 deficiency is common among all people—even meat lovers! A study published in the American Journal of Clinical Nutrition found that nearly 40% of the 3,000 adult participants under the age of 50 had blood levels of vitamin B12 low enough to cause serious health problems.
The good news is that it is virtually impossible to consume too much B12! B12 has a very low potential for toxicity, and no adverse effects have been associated with a high dosage of vitamin B12 in healthy individuals. Vitamin B12 supplements that contain 500 – 1,000 micrograms are generally safe for you, regardless of the dietary plan you follow.
However, believe it or not, symptoms of a vitamin B12 deficiency can take years to show up, and it can be somewhat difficult to diagnose. Vitamin B12 deficiencies are often mistaken for a folate deficiency—a condition in which there isn’t enough folic acid in the body.
Here are some signs and symptoms associated with a vitamin B12 deficiency:
Pale or Jaundiced Skin
Looking pale or having a slightly yellow tinge to your hands and/or the whites of your eyes is common with a B12 deficiency. The lack of B12 causes problems with the production of red blood cells in your body. This can lead to a type of anemia called megaloblastic anemia, in which the red blood cells produced in your bone marrow are too large and fragile to pass from your bone marrow and into your circulation. Because you don’t have as many red blood cells circulating in your body, your skin tends to appear pale in color.
Weakness and Fatigue
A low count of red blood cells also leads to tiredness, weakness, and fatigue because your body can’t effectively transport oxygen throughout your body. In older adults, this type of anemia is often caused by an autoimmune condition known as pernicious anemia.
Sensations of Pins and Needles
Nerve damage is one of the more severe side effects of a long-term B12 deficiency. Vitamin B12 contributes to the production of myelin—a critical fatty substance that insulates and protects your nerves for the proper function of your nervous system. Without B12, myelin is produced differently, and your nervous system isn’t able to function properly. One common sign of this happening is paresthesia or the sensation of pins and needles in your hands and feet.
Changes to Mobility
After a while, the damage to your nervous system caused by a B12 deficiency can lead to changes in the way you walk, move, and stand. This symptom is often seen in undiagnosed B12 deficiency in the elderly, as people over the age of 60 are more prone to a B12 deficiency than others. This symptom is only seen in young people in extreme cases.
In rare cases, the nervous system damage that is caused by a B12 deficiency can affect the optic nerve and lead to blurred or disturbed vision. Nervous system damage can disrupt the nervous signal that travels from your eye to your brain, impairing your vision. The good news is that this damage is often reversible with the supplementation of vitamin B12.
B12 Deficiency and Weight Gain
If you’re questioning whether or not a B12 deficiency leads to weight gain, the short answer is no. On the contrary, one of the significant symptoms associated with vitamin B12 deficiency is weight loss. A vitamin B12 deficiency tends to affect your digestive system, leading to a lot of indigestion and nausea-related problems causing a lack of appetite, vomiting, and weight loss. Chronic stomach pains can be a sign of a B12 deficiency.
Keep in mind that not all weight loss is good weight loss! If you are not actively trying to lose weight with proper nutrition and diet but are still experiencing weight loss, then you are properly suffering from a B12 deficiency. Weight loss is actually one of the first symptoms of a vitamin B12 deficiency.
Vitamin B12 Side Effects and Benefits
B12 Side Effects
Although there are not many side effects associated with B12 supplementation, there are some people who might not benefit from taking supplements of vitamin B12.
One research study from the Division of Nephrology at the University of Western Ontario found that people with diabetic nephropathy (loss of kidney function due to diabetes) experienced a more rapid decline in kidney function when supplemented with high-dose B vitamins. These same participants had a higher risk of heart attack, stroke, and death compared to the group of participants receiving a placebo.
A different research study in pregnant women also found that extremely high B12 levels due to vitamin supplementation increased the risk of autism spectrum disorder in their offspring(s).
Aside from these special cases, most studies have demonstrated that vitamin B12 supplements are generally a safe and effective way to treat a B12 deficiency.
Some of the science-based health benefits of vitamin B12 include:
- Efficient red blood cell formation and anemia prevention
- Can support bone health and prevent osteoporosis
- May reduce your risk of macular degeneration
- Can improve your mood and reduce feelings of anxiety and depression
- Can produce a boost of energy
- Can improve heart health by decreasing homocysteine
- Supports healthy hair, skin, and nails
Is Vitamin B12 Overdose Possible?
Because B12 is a water-soluble vitamin, it is generally considered safe, even when taken in high doses. This means that realistically, there is no such thing as a vitamin B12 overdose. No Tolerable Upper Intake Level (UL) has been established for B12, due to its low level of toxicity. This limit has not been set because any B12 that your body does not absorb gets eliminated by your body through urination.
Does B12 Help with Weight Loss
Not only does vitamin B12 help with weight loss, but it is actually one of the essential vitamins for weight loss. B12 helps with weight loss by assisting with the conversion of fats and protein into energy. High levels of B12 in your body allows your respiratory and circulatory system to function properly, promotes fat loss, and optimizes your weight loss results.
A B12 deficiency can also slow down your metabolism, conserving fat stores, and burning fewer calories throughout the day. So, if your goal is to lose weight, then make sure you are getting enough vitamin B12 in your diet, either from the foods you consume or through a B12 supplement.
How Much B12 Should I Take?
The amount of vitamin B12 you need each day depends on your age. The average daily recommended amounts for different ages are listed below in micrograms (mcg):
Are There Different Kinds of B12 Supplements?
If you get a sufficient amount of B12 from your diet, then you do not need to take B12 supplements. However, for those who would like to increase their intake of B12, there are a variety of B12 supplements to choose from.
B12 Shots and B12 Injection
B12 injections are a great alternative if you are following a strict diet plan that limits the amount of B12 you get from food sources. If your diet limits you, B12 injections are often the best way to prevent a B12 deficiency and stabilize energy levels in your body.
B12 injections can get pricey, so we recommended speaking to your doctor and doing a sufficient amount of research before opting to purchase a B12 injection supplement on your own.
Although sublingual B12 is often promoted and seen the B12 supplement with the best absorption, there isn’t much evidence backing this up. In fact, some clinical studies that compare the oral and sublingual supplementation of B12 have found that both forms are just as effective in terms of correcting a B12 deficiency.
If you opt to take a sublingual B12 supplement, watch out for a variety of sugar substitutes that are often found in these supplements. Sugar substitutes such as sorbitol, mannitol, and sucralose can cause gastrointestinal symptoms in people with a sensitive stomach.
Below are two well-reviewed and popular sublingual B12 supplements:
Methylcobalamin B12 is the form of vitamin B12 that is easiest for the body to absorb and use. It is typically used as a dietary supplement to treat certain anemias. In people with low levels of B12, methylcobalamin B12 supplements are highly effective in improving energy levels and restoring mental function.
Like many B12 supplements, you do not need a prescription to obtain or buy methylcobalamin B12. However, it may be harder to find at your local store and may not be as inexpensive as other B12 supplements.
You can give some of these well-reviewed methylcobalamin B12 supplements a try:
Many people don’t know the difference between cyanocobalamin B12 and methylcobalamin B12. Cyanocobalamin is a synthetic form of vitamin B12 found only in supplements because it does not occur naturally. Methylcobalamin, on the other hand, is a naturally occurring form that you can get through either food sources or supplements. Some studies have found that the difference in absorption and retention is minimal among these two different supplements.
The bottle and nutrition label should clarify whether or not a supplement contains cyanocobalamin B12 or methylcobalamin B12.
Vegan B12 Supplements
Aside from foods fortified with B12, the only reliable vegan sources of vitamin B12 are vegan B12 supplements. Most vegans consume enough B12 to avoid anemia and nervous system damage, but many do not get enough to minimize the potential risk of heart disease or pregnancy complications.
According to The Vegan Society, to get the full benefit of a vegan diet and avoid a B12 deficiency, vegans should do one of the following:
- Eat fortified foods two or three times a day to get at least three micrograms (mcg or µg) of B12 a day
- Take one B12 supplement daily providing at least 10 micrograms
- Take a weekly B12 supplement providing at least 2000 micrograms.
You can give some of these well-reviewed vegan B12 supplements a try:
Regardless of the dietary plan you follow, getting a sufficient amount of B12 is not only possible but also essential to your health. Because diagnosing a B12 deficiency can be relatively difficult, it is a good idea to ensure you are eating B12-rich foods or using a B12 supplement—preferably one that you’ve done your research on—to avoid a deficiency.