Can a B12 Deficiency Cause Jaundice? What Every Nutrition Diet Plan Needs to Address

October 13, 2025 •

4 min read

According to case reports, chronic jaundice can be an atypical presentation of vitamin B12 deficiency, particularly in individuals with dietary restrictions. This yellowing of the skin and eyes is a rare but documented symptom that arises from the underlying megaloblastic anemia caused by insufficient vitamin B12.

Quick Summary

Severe vitamin B12 deficiency can induce jaundice by causing megaloblastic anemia and premature red blood cell destruction. This leads to elevated bilirubin, resulting in yellowish skin and eyes. Timely diagnosis is crucial for effective treatment.

Key Points

Indirect Link: A B12 deficiency doesn't directly cause jaundice; it's a result of the hemolytic anemia that the deficiency causes.
Megaloblastic Anemia: Insufficient B12 leads to the production of large, immature, and fragile red blood cells (megaloblasts).
Bilirubin Buildup: Premature destruction of these fragile red blood cells releases excess bilirubin, which the liver cannot process, leading to the yellowing of the skin and eyes.
Risk Factors: High-risk groups include vegans, those with malabsorption disorders like pernicious anemia, and individuals who have had stomach or intestinal surgery.
Treatment is Effective: Addressing the underlying B12 deficiency with supplements or injections can reverse the hemolytic anemia and resolve the jaundice.
Early Diagnosis is Crucial: Misdiagnosing B12-induced jaundice as a liver problem or another blood disorder can delay proper and straightforward treatment.

While it's a less common presentation, yes, a B12 deficiency can cause jaundice. The mechanism behind this is rooted in the body's impaired ability to produce healthy red blood cells (RBCs). Vitamin B12 is essential for DNA synthesis and the proper maturation of blood cells in the bone marrow. When B12 is deficient, the bone marrow produces large, immature, and fragile RBCs, a condition known as megaloblastic anemia.

The Connection: Ineffective Erythropoiesis and Bilirubin

The jaundice caused by B12 deficiency is a result of a process called hemolytic anemia, where red blood cells are destroyed prematurely. Specifically, the defective and fragile red blood cells produced in the bone marrow are destroyed within the marrow itself, a phenomenon known as ineffective erythropoiesis. As these cells are broken down, they release a yellow pigment called bilirubin into the bloodstream.

Ordinarily, the liver processes bilirubin and excretes it, but with a severe B12 deficiency and high rates of red blood cell destruction, the liver can become overwhelmed. This leads to a build-up of unconjugated bilirubin, causing the characteristic yellowing of the skin, mucous membranes, and eyes associated with jaundice. Once the B12 deficiency is addressed, this cycle of hemolysis and ineffective erythropoiesis is corrected, and bilirubin levels return to normal.

Common Risk Factors for B12 Deficiency

Several factors can put an individual at a higher risk of developing a B12 deficiency and its associated complications, including jaundice. The most common causes are related to diet or malabsorption.

Inadequate Dietary Intake

Vegan or strict vegetarian diet: Since vitamin B12 is found almost exclusively in animal products, those who follow a strict vegan or vegetarian diet without supplementation are at high risk.
Malnutrition or restricted diets: Individuals with eating disorders or those who severely restrict their food intake may not get enough B12.

Impaired Absorption

Pernicious anemia: This autoimmune condition prevents the production of intrinsic factor, a protein necessary for B12 absorption in the small intestine. It is the most common cause of severe B12 deficiency in adults.
Gastric bypass or other stomach surgery: Surgical removal of parts of the stomach or intestine can impair B12 absorption.
Certain medications: Long-term use of certain drugs, such as metformin (for diabetes) and proton pump inhibitors (for reflux), can reduce B12 absorption.
Older age: As people age, their stomach acid production can decrease, making it harder to absorb vitamin B12 from food.

Gastrointestinal Disorders

Crohn's disease and celiac disease: These inflammatory conditions can damage the part of the small intestine where B12 is absorbed.
Chronic pancreatitis: Can disrupt the release of enzymes needed to free B12 from binding proteins in the gut.

Jaundice from B12 vs. Other Causes: A Comparison

To differentiate between B12-induced jaundice and other causes, healthcare providers use a range of diagnostic tests. The following table highlights some key distinguishing features. Consulting a healthcare professional for an accurate diagnosis is essential.


Characteristic	B12 Deficiency-Induced Jaundice	Other Common Causes (e.g., Obstructive)
Mechanism	Ineffective erythropoiesis and hemolysis cause high indirect bilirubin.	Blockage of bile ducts or liver disease causes high conjugated or mixed bilirubin.
Associated Anemia	Macrocytic, with large red blood cells (high MCV) and pancytopenia.	Anemia is often absent or normocytic, not typically macrocytic.
CBC Findings	High MCV, low reticulocyte count, hypersegmented neutrophils.	Varies, but does not typically include macrocytosis and hypersegmentation.
Bilirubin Profile	Primarily unconjugated (indirect) bilirubin is elevated.	Conjugated (direct) bilirubin is elevated.
Response to Treatment	Rapidly reverses with B12 supplementation.	Dependent on addressing the underlying liver disease or obstruction.

Diagnostic Approach and Treatment

The diagnostic process for B12 deficiency involves a combination of a physical examination, a review of symptoms, and blood tests. A complete blood count (CBC) can reveal the characteristic large red blood cells (macrocytosis). A serum B12 test confirms low levels, while elevated levels of methylmalonic acid (MMA) or homocysteine can help confirm a functional B12 deficiency even when serum levels are borderline.

For treatment, correcting the vitamin deficiency is key. This is most often done with vitamin B12 injections for severe cases or when malabsorption is the cause. High-dose oral supplementation can also be effective, especially for mild-to-moderate deficiency. The hemolytic anemia and jaundice often resolve within weeks of initiating treatment.

Conclusion: Prioritizing Nutrient Intake

While jaundice from a B12 deficiency is an unusual manifestation, it serves as a stark reminder of the critical role this nutrient plays in our health. A deficiency can lead to a host of other issues, including severe fatigue, neurological problems, and anemia. A balanced diet, especially for those at higher risk, is paramount. Those with malabsorption issues or on restricted diets should be proactive with supplementation and regular monitoring under medical supervision.

For more information on nutrition and vitamins, consult reputable health sources such as the National Institutes of Health. Learn more about vitamins and supplements from the NIH.

Frequently Asked Questions

A severe B12 deficiency impairs the production of healthy red blood cells, leading to megaloblastic anemia. These abnormal red blood cells are fragile and break down prematurely, releasing a yellow pigment called bilirubin into the bloodstream. When the liver cannot process this excess bilirubin, jaundice occurs.

The condition is known as megaloblastic anemia, which can also present with hemolytic features. The red blood cells are abnormally large (macrocytic), and their premature destruction is the cause of the jaundice.

Beyond jaundice, symptoms can include severe fatigue, pale skin, glossitis (a sore and swollen tongue), numbness or tingling in the hands and feet (paresthesia), and neurological or psychological changes.

Diagnosis typically involves a blood test to check serum B12 levels. A complete blood count (CBC) will show macrocytosis (enlarged red blood cells). Blood tests will also show elevated levels of bilirubin, LDH (lactate dehydrogenase), and sometimes methylmalonic acid (MMA).

Yes, it can. Because jaundice is commonly associated with liver disease, it is crucial for doctors to consider B12 deficiency in the differential diagnosis. A full workup, including a CBC and bilirubin fractionation, can distinguish the cause.

Risk factors include following a vegan diet without supplementation, having an autoimmune disorder like pernicious anemia, undergoing gastric bypass surgery, or having malabsorption issues from conditions like Crohn's disease.

With appropriate vitamin B12 supplementation, either via injections or high-dose oral tablets, the hemolytic process can resolve, and bilirubin levels can normalize, often leading to a noticeable improvement in jaundice within a few weeks to months.