A healthful diet and exercise plan go a long way toward weight loss, but when you need an extra boost, you might want to look into vitamin deficiencies in your diet. Vitamin B12 is one nutrient that, if lacking, could defeat your weight loss goals.
What is vitamin B12?
Also known as cobalamine, vitamin B12 is necessary for almost every function of the body, brain and nervous system, including metabolism, fatty acid synthesis, and energy production. Your body needs this water-soluble vitamin in order to produce red blood cells, which carry oxygen to all of the body’s tissues to provide energy. Lacking enough red blood cells to fuel your body with oxygen can lead to a certain type of anemia.
The liver stores B12 in large amounts, which the body can use in many cases of deficiency.
Health benefits of vitamin B12
Because vitamin B12 is so necessary to the body’s functions, maintaining the proper levels benefits you in a number of ways, including the following:
- Improves cholesterol levels to guard against heart disease
- Protects against certain cancers
- Helps maintain healthy skin, hair, and nails
Sources of vitamin B12
The recommended daily amount of vitamin B12 for adults is 2-3 mcg per day, and pregnant women or women who are nursing may require slightly more. It’s simple for most people to meet B12 requirements, though, as this critical vitamin is present in many foods:
- Seafood, particularly shellfish
- Cheese and Dairy
- Fortified cereals
Some of the foods listed above can provide up to 600% of the daily recommended intake of vitamin B12. Because B12 has very low toxicity, taking it in higher doses is not harmful.
In the 1920s, liver was a recommended treatment for B12 deficiency. While animal liver is a good source of B12, the extremely high levels of vitamin A, heavy metals, and possibly other toxins outweighs the benefits liver provides.
Symptoms of B12 deficiency
Even with the prevalence of vitamin B12-rich foods, a deficiency in this vitamin is common and may affect as much as 15% of the general population. Because B12 is necessary in so many of the body’s functions, the signs of a deficiency of this vitamin cover a large spectrum:
- Megaloblastic anemia
- Fatigue and weakness
- Loss of appetite and weight loss
- Difficulty maintaining balance
- Confusion and poor memory
- Soreness of the mouth or tongue
Experiencing any of these symptoms above will make it difficult for you to expend the energy you need to keep your body fit, let alone maintain healthy weight loss. None of these symptoms is enough on its own to diagnose a B12 deficiency, so please speak with your doctor if you are experiencing these signs and suspect additional vitamin B12 could benefit you.
Megaloblastic anemia occurs when DNA synthesis of red blood cells is impaired. Red blood cells are produced but they do not split, which creates red blood cells that are larger than normal and inefficient at supplying your body’s tissues with oxygen.
Who’s at risk of B12 deficiency?
Though vegans and people with poor diets are at risk of a deficiency, there are several reasons a person may be deficient in B12 even if he or she is eating more than the daily recommended amount. Some conditions cause people to have trouble absorbing B12 in their bloodstream, sometimes due to a lack of intrinsic factor—they are intrinsically incapable of absorbing the nutrients in the food they eat.
People at risk may include:
- Older adults
- Those with pernicious anemia (the stomach destroys the ability to absorb B12)
- Those with intestinal disorders, including Celiac disease and Crohn’s disease
In situations where the body lacks the intrinsic factor to absorb B12, oral supplements or B12 injections may be necessary to maintain proper levels. High nicotine and alcohol intake can also prevent the body from absorbing the B12 you ingest from your diet.
Do you need additional B12?
For people who are deficient in vitamin B12, increasing the intake levels can provide the energy they need to exercise at higher intensity for weight loss. Your doctor can recommend oral supplements or prescribe injections after an examination and possibly a blood test to diagnose anemia. These supplements may interact with certain medications as well as alcohol, so it is important to speak with your doctor if you are taking any of the following:
- Aminosalicylic acid
- Hormonal contraception
- Colestipol and cholestyramine
- H2-receptor antagonists
- Proton pump inhibitors
- Folic acid
Taking the medications above along with supplements could decrease or block the body’s ability to absorb B12 and, in some cases, may lead to megaloblastic anemia.
Will additional B12 help with weight loss?
For those with a vitamin deficiency, additional B12 could be the ingredient they’re missing in their diet to maximize the benefits of their workouts and meal plan. Depression, weakness, fatigue, and anemia—all symptoms of B12 deficiency—can undermine attempts to lead a healthy lifestyle, and supplements can help eradicate these symptoms.
However, if you eat a healthful, balanced diet and do not exhibit any of the above symptoms for a B12 deficiency, it is unlikely additional B12 will provide any extra energy or a higher metabolism to propel your weight loss. Vitamin B12 above and beyond your daily requirements will not provide an extra boost.
Some weight loss clinics administer these shots as part of their overall weight-management program, and while they may boost energy as part of a placebo effect, it is unlikely that most or many of these people are suffering from a deficiency that necessitates such supplements. There is no maximum recommended level of B12 due to its low toxicity, so the shots may not be physically harmful, but the cost and discomfort are probably not necessary in order for you to meet your weight loss goals.