Nutrition

Is Your Body Craving B12?

Is Your Body Craving B12?
If you plan or prepare meals for vegetarians, have them as patients, are thinking about becoming a vegan, have been one for more than a year, desire to eat healthy, have a compromised immune system, take antacids regularly, have had gastric bypass surgery, are pregnant or trying to conceive a child, have numbness or tingling in extremities, or are near 50 years of age, continue reading this compre­hensive article to prevent serious illness and expensive medical bills.

Make Certain You Have Enough B12

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Regardless of food choices, our goal is to stay healthy, right? Vitamin B12 (also known as methylco­balamin, cyano­co­balamin or cobalamin) is an indis­pensable nutrient commonly found in a variety of non-plant based foods. This includes fish, shellfish, meat, eggs, and dairy products.

Because animal products provide optimum food sources for vitamin B12, vegans have the greatest risk for deficiency. Vegetarians who eat eggs and milk products are also at risk because, on average, they consume less than half of the adult Recommended Dietary Allowance (RDA) of vitamin B12. [1,2]

Symptoms of Vitamin B12 Malnutrition

Our bodies send out unpleasant signals when they crave essential nutrients. Early vitamin B12 cravings include decreased energy: weakness, fatigue, light-headedness, rapid heartbeat (tachy­cardia), panting; dermato­logical and dental indictions: pallor, easy bruising, sore tongue, bleeding gums; gastric disturbance: upset stomach, weight loss, diarrhea or constipation.

Vitamin B12 deficiency can ultimately lead to several neurological and cardio­vascular problems, including paresthesia (numb or painful extremities), cold hands and feet, depression, dementia [2] and cardiac distress.

Vitamin B12 is required for proper red blood cell formation, neurological function, and DNA synthesis.

A normally functioning liver stores an adequate reserve of vitamin B12 for several years. Vegans are advised to have their B12 level checked every two years via methyl­malonic acid (MAA) urine testing due to the unreliability of blood tests.

Algae and other plant foods contain B12-analogues (false B12) that can imitate true B12 in blood tests while actually interfering with B12 meta­bolism. Values below approximately 170–250 pg/mL (120–180 picomoles/L) for adults indicate a vitamin B12 deficiency. [3,4]

Not Just Vegans At Risk

Vitamin B12 is required for proper red blood cell forma­tion, neurological function, and DNA synthesis. Vitamin B12 deficiency can have a number of possible causes. Typically it occurs in people whose diges­tive systems do not adequately absorb the vitamin from the foods they eat. [2,3] This can result from:

  • Pernicious anemia, a condition in which there is a lack of a protein called intrinsic factor. The protein, which is made in the stomach, is necessary for vitamin B12 absorption.
  • Atrophic gastritis, a thinning of the stomach lining that affects up to 30% of people aged 50 and older.
  • Surgery in which part of the stomach and/or small intestine is removed.
  • Small intestine conditions, such as Crohn’s disease, celiac disease, bacterial growth, or a parasite.
  • Excessive alcohol excess consumption.
  • Immune disorders, such as Graves’ disease, systemic lupus erythematosus or HIV.
  • Antacid abuse.

Our bodies don’t produce vitamin B12. The RDA is 4 to 7 mcg per day for most adults. More is advised to actually absorb this amount. (NutritionFacts.org) A developing infant depletes its mother’s supply. Most women take folic acid in a prenatal vitamin during preg­nancy. While folic acid is important for preventing birth defects, it can also “mask” some of the signs of a vitamin B12 malnutrition, making a deficiency much more difficult to detect. For proper care, expectant mothers should inform their Ob/Gyn if they are vegans.

Optimum Food Sources For B12

The easiest way for the average person to maintain adequate levels of vitamin B12 is to ingest it within foods. A full day’s supply of vitamin B12 can be obtained by eating 1 egg with a bowl of fortified cereal, 1 chicken breast, and 1 cup of plain yogurt. As the following table reveals, people with plant-based diet restrictions are primarily limited to fortified foods (and perhaps tempeh and raw seaweeds with a caveat). **


Food [3]

Serving Size
Micro­grams
(mcg)
per serving

Per­cent DV*
Clams, cooked3 ounces84.11,402
Liver, beef, cooked3 ounces70.71,178
Nori Seaweed, raw ** [4]3 ounces46.8780
Kombu Seaweed, raw ** [4]3 ounces23.0383
Breakfast cereals, fortified with 100% of the DV for vitamin B121 serving6.0100
Trout, rainbow, wild, cooked3 ounces5.490
Salmon, sockeye, cooked3 ounces4.880
Temepeh ** [4]3 ounces4.371
Trout, rainbow, farmed, cooked3 ounces3.558
Tuna fish, light, canned in water3 ounces2.542
Cheeseburger, double patty and bun1 sand­wich2.135
Haddock, cooked3 ounces1.830
Breakfast cereals, fortified with 25% of the DV for vitamin B121 serving1.525
Beef, top sirloin, broiled3 ounces1.423
Milk, low-fat1 cup1.218
Yogurt, fruit, low-fat8 ounces1.118
Cheese, Swiss1 ounce0.915
Beef taco1 soft taco0.915
Ham, cured, roasted3 ounces0.610
Egg, whole, hard boiled1 large0.610
Chicken, breast meat, roasted3 ounces0.35

*DV = Daily Value. DVs were developed by the U.S. Food and Drug Administration (FDA) to help consumers determine the level of various nutrients in a standard serving of food in relation to their approximate requirement for it. The DV for vitamin B12 is 6.0 mcg. However, the FDA does not require food labels to list vitamin B12 content unless a food has been fortified with this nutrient.

Foods providing 20% or more of the DV are considered to be high sources of a nutrient, but foods providing lower percentages of the DV also contribute to a healthful diet. To find the best sources of vitamin B12, the U.S. Department of Agriculture’s Nutrient Database website [5] lists the nutrient content of many foods and provides a comprehensive list of foods [PDF] containing vitamin B12.

Vitamin B12 Supplements

A macrobiotic diet typically consists of 50–60% whole cereal grains, 5% soups, 20–25% vege­tables, and 5–10% beans and sea vege­tables. Occasionally, small quantities of other foods, such as seafood, may be included. Meat is avoided and little or no dairy or eggs are eaten. Vitamin supplements generally are not taken. [6]

Trace amounts of vitamin B12 can be found within tempeh, seaweeds and organic plants in specific geographic regions.** But unless and until these foods are shown consistently to correct vitamin B12 deficiency, vegans should not rely on them as a vitamin B12 source. [6]

Spirulina Tablets

Sadly, many raw vegans think they are ingesting plant-based vitamin B12 but in reality they aren't. Spirulina is not considered to be a reliable source of vitamin B12. Spirulina is a microalga supplement that predomi­nantly contains pseudovitamin B12, which is bio­logically inactive in humans.

Therefore, it is not possible to get sufficient amounts of vitamin B12 by eating unwashed organic produce, seaweeds or mushrooms grown in B12-rich soil. [7,8] Vitamin B12 can be produced industrially only through bacterial fermination-synthesis for supplements and fortification.

To prevent malnourishment, Dr. Andrew Weil recommends taking 50 mcg as part of a B-Complex that contains a full spectrum of B vitamins, including biotin, thiamine, B12, riboflavin and niacin. [9,14] If for any reason you choose to avoid fortified foods or supplements, recognize that you are carrying out a dangerous experi­ment that many have tried before with consistently low levels of success. [10]

To get the full benefit on a vegan diet, do one of the following:

  • Eat fortified foods 2 or 3 times a day to get at least 3 mcg B12 a day.
  • Take one sublingual B12 supplement daily providing at least 10 mcg.
  • Take a weekly sublingual B12 supplement providing at least 2000 mcg.
  • Take supplement prescribed by personal physician.

Apart from other B vitamins, B12 tablets should be slowly dissolved beneath the tongue. This is comparable to B12 injections. Oral and sublingual tablets are available.

Take care that excess heating or pre-washing water-soluble vitamins, like B12, may destroy their potency. Most water-soluble vitamins breakdown quickly and are absorbed into the bloodstream. Generally, they cannot be amassed in our body and thus need to be consumed everyday.

Instead of filtering and excreting the excess like other water-soluble vitamins, your body stores some B12 in your liver. Outside of darkened urine, which may mask other genitourinary problems, there are usually no other symptoms of overconsumption, though vitamin B12 is contraindicated with surgical stents, some medicines, and pre-existing medical conditions.

Vegetarian B12 Requirements

This is no treatise against veganism. Being informed may determine whether any of us decides to include animal products (like eggs, cheese or yogurt) in our diet or not. Consider the information presented as important guidelines to becoming a success­ful vegan, vegetarian, pescatarian or flexitarian, if you will. [11]

We should not assume that because we are eating mostly vege­tables we must be healthy. Whether motivated by concern for animals, environ­mental impact, excessive antibiotics in the meat supply or a desire to minimize fats and lose weight, a vegetarian or vegan diet requires planing. [12] Along with a variety of the best fresh fruits and vege­tables, we must include essential protein, omega-3, calcium, vitamin D and vitamin B12 as part of our regular nutrition.

Persons over 50 are advised to take a B12 supple­ment even if they consume animal products. Vitamin B12 defi­ciency symptoms intersect cardio­vascular, endocrino­logical, derma­to­logical, urology, gastro­entero­logical, rheumatological, neurological, and obstetrics specialties. If you have health issues, it is wise to consult with a qualified physician before pursuing alter­native health remedies. B12 levels are measured with a blood test.

  • Normal range for vitamin B12 in the blood is between 200 and 900 nanograms per milliliter (ng/mL). Follow-up testing may be required based upon symptoms.
  • Low levels of vitamin B12 are below 200 ng/mL. This suggests a vitamin B12 deficiency, pernicious anemia, or an overactive thyroid. People with low vitamin B12 levels often experience neurological symptoms.
  • High vitamin B12 level is anything over 900 ng/mL. This may suggest liver or kidney problems, diabetes, or certain forms of leukemia.

Are you craving vitamin B12? You should be, whether you are symptomatic or not. It’s an essential vitamin affecting our energy, skin, digestion, heart function, genetic reproduction and thought processes. Which source will you choose? Nutritional guidelines are available for vegans/vegetarians from ChooseMyPlate.gov. [13]

Vitamin B12 Overview

Is Your Body Craving B12?

Everything you want to know about vitamin B12 but were afraid to ask: [14]

Vitamin B12 is required for the proper function and development of the brain, nerves, blood cells and many other parts of the body.

Vitamin B12 is useful in treating and preventing vitamin B12 deficiency, a condition in which B12 levels in the blood are too low. It is also used to treat pernicious anemia, a serious type of anemia that is due to vitamin

B12 deficiency and is found mostly in older people. For this purpose, people use either a supplement that is taken by mouth (sublingually) or a gel that is applied inside the nose.

Vitamin B12 is also used for memory loss, Alzheimer’s disease, boosting mood, energy, concentra­tion and the immune system, and slowing aging. It is prescribed for heart disease, lowering high homocysteine levels (which may contribute to cardio­vascular disease), male infertility, diabetes, sleep disorders, depression, mental disorders, weak bones (osteo­porosis), swollen tendons, AIDS, inflammatory bowel disease, asthma, allergies, a skin disease called vitiligo, preventing cervical and other cancers, and skin infections.

Some people receive vitamin B12 for amyo­trophic lateral sclerosis (Lou Gehrig’s disease), multiple sclerosis, preventing the eye disease age-related macular degeneration (AMD), Lyme disease and gum disease. It is also used for ringing in the ears, bleeding, liverand kidney disease, and for protection against the poisons and allergens in tobacco smoke.

As a dermatological treatment for psoriasis and eczema, vitamin B12 is applied to skin either alone or in com­bina­tion with avocado oil. Vitamin B12 is frequently used in com­bina­tion with other B vitamins in vitamin B-complex products. [14]

B12 Injections For Weight Loss?

Some weight-loss clinics offer vitamin B12 injections. Propo­nents of the injections say the shots provide more energy and boost meta­bolism, helping to shed unwanted pounds. But unless there is a vitamin B12 deficiency, such injections are not likely to offer any energy boost.

Getting large amounts of vitamin B12 through injections isn’t likely to harm your health. Arguably, it is no better than sublingual tablets or drops. Vitamin B12 can interfere with the effectiveness of some medications or stents, so if you receive vitamin B12 injections, be sure to let your doctor know. [15]

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To support the writing of useful articles about nutrition, ClinicalPosters sells human anatomy charts, scientific posters, and other products online. You may sponsor specific articles or remit a small donation.

ClinicalPosters sells human anatomy charts, scientific posters, and other products online to offset expense of the writing useful articles about nutrition. Slide extra posters into DeuPair Frames without removing from the wall.

ClinicalPosters sells human anatomy charts, scientific posters, and other products online. You may remit a small donation.

You can support the writing of useful articles about nutrition by sponsoring specific articles or remitting a small donation. Visible content is optimized for device size.

Check out the informative NutritionFacts.org video for a shocking commentary on the Safest Source of B12. Get the useful poster to hang on your wall entitled Understanding Nutrition.

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