5/5 - (1 vote)

My dog Scout almost daily puked at 3 a.m. for several months in the summer of 2022. Dog owners will be familiar with the noise. And each time, she ate her mess before I could even get to it, making it difficult to determine the root of the problem.

The veterinarian and I ultimately decided that my hydrangeas were the cause of the issue, but keeping Scout away from them wasn’t effective. She began to appear exhausted all the time, which was extremely unsettling in a typically hyper yellow Lab puppy.

Then, one day, a peculiar hairball—not just any hairball—was thrown up by Scout. Hair often moves through the digestive system of dogs without difficulty, but this particular hairball was wrapped around a brillo pad that was too large to pass through. The overnight vomiting stopped as soon as this foreign object was taken out. But despite this, Scout required treatment because the object had prevented her body from absorbing vitamin B12 at a crucial stage. B12 is a crucial nutrient needed for the healthy operation of nerves, blood cells, and many other vital bodily functions.

Even though I educate college students about nutrition and food science and am a licenced dietitian, I failed to recognise the B12 shortage that was the root of my puppy’s weariness. Despite the fact that B12 deficiency is a widespread health issue that affects between 6% and 20% of Americans, doctors can just as readily be blind to it in patients.

The diet is deficient in B12, which is only available in foods derived from animals. The good news is that humans only require 2.4 micrograms of B12 every day, or one ten-millionth of an ounce – a very, very small quantity. The body’s general health and quality of life suffer when B12 levels are insufficient.

Signs and symptoms

Fatigue is one of the main signs of a B12 deficiency, a state of extreme fatigue or exhaustion that interferes with day-to-day activity.

Other neurological symptoms can include numbness or tingling in the limbs, confusion, memory loss, sadness, and trouble staying balanced. If the vitamin shortage is not treated, several of these conditions can become permanent.

But because there are so many potential explanations for these symptoms, medical professionals can ignore the likelihood of a B12 shortage and neglect to screen for it. A good diet may also appear to rule out any vitamin deficiencies. As an illustration, because I was confident in Scout’s healthy diet, I disregarded a B12 shortage as the cause of her issues.

How B12 is absorbed

According to research, those who eat a plant-based diet must take B12 supplements at proportions usually found in multivitamins. However, hundreds of millions of Americans who do take B12 supplements may also be at danger due to illnesses that can prevent their bodies from absorbing B12.

The intricate multistep process of absorbing vitamin B12 starts in the mouth and ends at the very end of the small intestine. Saliva and food are combined during chewing. R-protein, a component of saliva that shields vitamin B12 from being dissolved by stomach acid, travels to the stomach with the food when it is swallowed.

Two chemicals secreted by particular stomach lining cells known as parietal cells are crucial for B12 absorption. One is stomach acid, which separates food and B12 so that the vitamin can bind to the R-protein in saliva. The second material, known as intrinsic factor, combines with the stomach’s contents and follows them into the duodenum, which is the first segment of the small intestine. Pancreatic juices release B12 from R-protein once in the duodenum and give it to intrinsic factor. This combination enables B12 to enter cells where it can support the formation of healthy red blood cells and sustain nerve cells.

Typically, a B12 deficit results from a breakdown at one or more of these steps in the absorption process.

Risk factors for a B12 deficiency


Without saliva, B12 cannot bind to the R-protein in saliva and cannot be absorbed by the body. And there are thousands of different medications that might make you feel dry-mouthed and reduce your saliva production. They include benzodiazepines, such as Xanax, which are used to treat anxiety, as well as opioids, inhalers, decongestants, blood pressure medications, and antidepressants.

In the United States, the final three categories alone account for easily 100 million prescriptions annually.

Low amounts of stomach acid may also contribute to a B12 deficiency. Numerous millions of Americans take anti-ulcer drugs to lessen the stomach acids that cause ulcers. Although that likelihood might not outweigh the requirement for the prescription, researchers have conclusively connected the usage of these treatments to B12 insufficiency.

Aging might also cause the production of stomach acid to decrease. In the United States, more than 60 million people are over 60, and about 54 million are over 65. This demographic has a higher risk of B12 deficiency, which may be made worse by the use of drugs that lower acid in the body.

It is essential for B12 absorption that gastric acid and intrinsic factor are produced by the stomach’s specialised parietal cells. However, harm to the stomach lining can stop both from being produced.

Gastric bypass surgery, ongoing inflammation, or pernicious anaemia, a disease with a long list of accompanying symptoms, are the three main causes of damaged stomach lining in people.

Insufficient pancreatic function is another frequent cause of B12 insufficiency. A B12 deficiency develops in about one-third of patients with impaired pancreatic function.

Last but not least, B12 deficiency has long been linked to the drug metformin, which is used to treat Type 2 diabetes by about 92 million Americans.

B12 insufficiency treatment
While certain medical professionals regularly evaluate patients’ levels of vitamins like B12 and others, a conventional well-check test only includes a complete blood count and a metabolic panel, neither of which checks a patient’s B12 status. You should visit a doctor to be checked if you have any symptoms that could indicate a B12 deficiency and one of the risk factors listed above. To find out or rule out whether low B12 levels could be involved, a thorough lab analysis and consultation with a doctor are required.

My dog Scout’s symptoms prompted the veterinarian to order two blood tests: a B12 test and a complete blood count. For humans, these make excellent starting points as well. After a while, Scout’s symptoms subsided.

The origin and severity of the B12 deficiency in humans determine the type of treatment and length of recovery. Although a full recovery can take up to a year, it is extremely likely with the right care.

Treatment for a B12 deficiency might be oral, given sublingually or nasally, or it may call for different kinds of injections. As it was for Scout, a B12 supplement or well-balanced multivitamin may be sufficient to address the deficit, but it is important to collaborate with a healthcare professional to ensure accurate diagnosis and treatment.

Leave a Reply

Your email address will not be published. Required fields are marked *