What are the symptoms of a vitamin B2 deficiency?: A comprehensive nutrition guide

October 6, 2025 •

4 min read

Vitamin B2 deficiency, or ariboflavinosis, is uncommon in many developed nations due to food fortification but remains a concern in populations with limited access to riboflavin-rich foods. This condition often presents with a combination of non-specific symptoms affecting the skin, mouth, and eyes, and typically co-occurs with other B vitamin deficiencies. Recognizing what are the symptoms of a vitamin B2 deficiency is the first step toward correcting this nutritional issue.

Quick Summary

A riboflavin deficiency can cause painful cracks at the corners of the mouth and on the lips, a magenta-colored tongue, and skin rashes. Patients may also experience red, itchy eyes, sensitivity to light, fatigue, and anemia. In severe, prolonged cases, more serious eye conditions and nerve damage can develop.

Key Points

Oral Manifestations: Cracked lips (cheilosis) and painful sores at the corners of the mouth (angular cheilitis) are classic signs of a riboflavin deficiency.
Skin Problems: A red, scaly, and greasy rash, known as seborrheic dermatitis, may appear around the nose, mouth, ears, and eyelids.
Eye Issues: Symptoms include red, itchy eyes, sensitivity to light (photophobia), and, in severe cases, cataracts.
Systemic Symptoms: Other common symptoms include a sore, magenta-colored tongue (glossitis), general fatigue, and anemia.
At-Risk Groups: Individuals on restricted diets (vegans, those with low dairy intake), chronic alcohol users, and people with malabsorption issues are most vulnerable.
Effective Treatment: Deficiency can often be corrected with dietary changes and oral riboflavin supplements, which typically reverse symptoms quickly.

The Vital Role of Riboflavin

Riboflavin, or vitamin B2, is a water-soluble vitamin essential for numerous metabolic processes in the human body. It is a key component of two vital coenzymes, flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD), which play a central role in energy production, cellular growth, and function. Riboflavin aids in the breakdown of carbohydrates, proteins, and fats to produce energy. Furthermore, it assists in the metabolism of other vital nutrients, including converting vitamin B6 to its active coenzyme form and maintaining healthy levels of homocysteine, an amino acid linked to cardiovascular health. Without sufficient riboflavin, these fundamental processes are compromised, leading to a wide range of physical symptoms.

Recognizing the Signs of Deficiency (Ariboflavinosis)

Ariboflavinosis typically presents with a collection of symptoms affecting the skin and mucous membranes. These signs often appear gradually and can be mistaken for other conditions, making proper diagnosis dependent on a thorough medical and dietary history.

Oral and Mucosal Symptoms

Oral and throat-related signs are common indicators of riboflavin deficiency. These can include painful cracks at the corners of the mouth (angular cheilitis), which may become infected, as well as swollen and cracked lips (cheilosis). The tongue can become sore, swollen, and appear a vibrant magenta color (glossitis), sometimes becoming smooth and shiny due to papillae atrophy. A sore throat is also a frequent complaint.

Skin Conditions

Riboflavin deficiency can impact skin health, causing a red, scaly, and greasy rash known as seborrheic dermatitis, often on the face, eyelids, and ears, or in the genital area. Some individuals may also experience hair loss.

Ocular (Eye) Manifestations

Eyes are sensitive to riboflavin levels, and deficiency can lead to visual problems like red, itchy eyes (conjunctivitis) and increased sensitivity to bright light (photophobia). More severe, prolonged deficiency can result in new blood vessel formation in the cornea (corneal vascularization) and potentially cataracts.

General and Systemic Symptoms

Beyond visible signs, a lack of vitamin B2 can affect overall health, potentially leading to a mild form of anemia by interfering with iron, general weakness and fatigue, and in some cases, neurological changes.

Who is at Risk?

Certain individuals have a higher risk of developing riboflavin deficiency, even in areas where it's generally uncommon:

Those with poor diets lacking dairy, meat, and fortified grains.
Individuals who chronically consume alcohol.
People with malabsorption syndromes like celiac disease or chronic diarrhea.
Pregnant and breastfeeding women due to increased nutritional needs.
Vegans and those with low milk intake.
The elderly and those with chronic illnesses.
Individuals on certain long-term medications, such as barbiturates.

Diagnosing and Treating Riboflavin Deficiency

Diagnosis often relies on clinical symptoms and risk factors, but can be confirmed by measuring erythrocyte glutathione reductase activity. Treatment is typically effective and symptoms often improve quickly. This involves:

Dietary Changes: Increasing intake of riboflavin-rich foods like dairy, meat, and fortified cereals.
Oral Supplements: Healthcare providers may recommend supplements as part of a treatment plan.
Addressing Underlying Issues: If malabsorption or other conditions are the cause, they need treatment to prevent recurrence.

Excellent Food Sources of Riboflavin

To prevent deficiency, ensure adequate daily riboflavin intake. Good sources include:

Dairy products like milk, cheese, and yogurt
Organ and lean meats, poultry, and fish
Eggs
Green leafy vegetables such as spinach, broccoli, and asparagus
Fortified cereals and breads
Mushrooms

Since light can degrade riboflavin, store these foods in opaque containers when possible.

Symptom Severity Comparison: Mild vs. Severe Ariboflavinosis


Symptom Area	Mild Deficiency	Severe/Prolonged Deficiency
Oral/Mucosal	Angular cheilitis (cracked mouth corners), cracked lips, sore throat, mild glossitis (sore tongue)	Pronounced cheilosis and angular stomatitis, magenta tongue, widespread oral lesions
Dermatological	Mild, non-specific skin rashes and scaling	Distinct seborrheic dermatitis on face, eyelids, and genitals, hair loss
Ocular	Eye irritation, redness, and itching	Photophobia (light sensitivity), blurred vision, corneal vascularization, risk of cataracts
Systemic	Fatigue, weakness	Anemia, degenerative changes in the nervous system, impaired nutrient metabolism

Conclusion

While ariboflavinosis is not common in many developed countries due to fortified foods, understanding what are the symptoms of a vitamin B2 deficiency is still crucial, particularly for at-risk groups. The signs, including oral lesions, dermatitis, and eye problems, can significantly impact quality of life. The good news is that these symptoms are typically reversible with appropriate treatment. By maintaining a balanced diet rich in riboflavin from sources like dairy, meat, and fortified grains, and addressing any underlying medical conditions, individuals can prevent this deficiency and its associated health problems. Consult a healthcare provider if you suspect a nutritional deficiency for a proper diagnosis and treatment plan.

For more information on recommended dietary allowances and the benefits of riboflavin, visit the NIH Office of Dietary Supplements.

Frequently Asked Questions

The most common cause is inadequate dietary intake, often due to a poor diet lacking riboflavin-rich foods like dairy, meat, and fortified cereals.

Clinical symptoms of riboflavin deficiency usually appear only after several months of insufficient intake. Less severe signs, however, may begin earlier.

Yes, riboflavin deficiency can interfere with the body's iron metabolism and absorption, which can lead to a type of anemia.

No, riboflavin deficiency is rare in developed countries due to widespread food fortification and varied diets. However, certain at-risk groups, like pregnant women, vegans, and alcoholics, can still be affected.

While improving diet is crucial, oral supplements of riboflavin are often used as part of a treatment strategy for an existing deficiency to help resolve symptoms quickly.

Cheilosis refers to the general swelling and cracking of the lips, while angular cheilitis is the specific term for the painful fissures that form at the corners of the mouth.

The best way to prevent a deficiency is to eat a balanced diet that includes good sources of riboflavin, such as dairy products, meat, eggs, and fortified grain products.

Riboflavin is a water-soluble vitamin, so any excess is typically excreted in the urine. As a result, riboflavin has no known toxicity, even at high doses.