What are the symptoms of too little riboflavin?

November 23, 2025 •

3 min read

According to the National Institutes of Health, riboflavin (Vitamin B2) deficiency, known as ariboflavinosis, is rare in developed countries but still occurs in vulnerable populations. It is most often seen alongside other B vitamin deficiencies and can manifest in various ways, affecting the mouth, skin, and nervous system.

Quick Summary

A deficiency in riboflavin, or Vitamin B2, causes symptoms like sore throats, skin disorders, and swollen lips or tongue. It can also lead to fatigue, eye issues, and, in severe cases, anemia, often occurring with other nutritional deficiencies.

Key Points

Mouth and Throat Issues: Riboflavin deficiency often presents with cracked lips (cheilosis) and inflamed corners of the mouth (angular stomatitis).
Skin Problems: Seborrheic dermatitis, a greasy and scaly rash, commonly appears on the face and genital areas due to a lack of Vitamin B2.
Eye Sensitivity: Individuals may experience red, itchy, and burning eyes, along with an increased sensitivity to light (photophobia).
Fatigue and Weakness: A general feeling of weakness and fatigue is common, as riboflavin is crucial for energy production in the body.
Potential for Anemia and Cataracts: Severe or prolonged deficiency can lead to anemia and, in advanced cases, the development of cataracts.
Associated with Other Deficiencies: Ariboflavinosis is often accompanied by deficiencies in other B vitamins and is frequently linked to underlying health conditions or poor dietary intake.

Common Physical Signs of Low Riboflavin

One of the most noticeable indicators of insufficient riboflavin is the effect it has on the mouth and throat. The corners of the mouth can become cracked and fissured, a condition known as angular stomatitis or cheilosis. This cracking can sometimes become infected with Candida albicans, leading to grayish-white lesions called perlèche. The tongue is also affected, becoming sore and swollen (glossitis), and may turn a distinctive magenta color. Additionally, the mucous membranes of the mouth and throat can appear swollen and inflamed.

Skin Conditions Linked to Ariboflavinosis

Skin problems are another common manifestation of a riboflavin deficit. A red, greasy, scaly rash known as seborrheic dermatitis can appear on specific areas of the body. These affected areas often include the nasolabial folds (the lines extending from the nose to the corners of the mouth), the ears, eyelids, and the genital regions. This dermatitis can cause significant discomfort and, like other symptoms, is a sign that the body’s metabolic processes are being hindered by the lack of Vitamin B2.

Ocular and Neurological Symptoms

The eyes are also susceptible to issues from a lack of riboflavin. Symptoms can include itchy, red eyes, light sensitivity (photophobia), and a burning sensation. In more severe or prolonged cases, neovascularization (the growth of new blood vessels) and keratitis of the cornea can occur. Fatigue and a general feeling of weakness are also reported, as riboflavin plays a critical role in cellular energy production. In some instances, severe and prolonged deficiency may even contribute to neurological issues and depression.

Causes, Diagnosis, and Treatment

What Causes Riboflavin Deficiency?

Primary riboflavin deficiency typically results from inadequate dietary intake, especially in populations with limited access to dairy products, fortified grains, and meats. Secondary deficiency can arise from other health factors, including malabsorption syndromes, chronic diarrhea, and liver disorders. Chronic alcohol use and certain medical procedures like hemodialysis can also increase the risk. Those with higher needs, such as pregnant or lactating women, athletes, and the elderly, may also be more susceptible.

How is Riboflavin Deficiency Diagnosed?

Diagnosis is usually based on a combination of clinical symptoms and patient history. Medical professionals may measure urinary riboflavin excretion to assess the body's status. A therapeutic trial of riboflavin supplementation can also be used to confirm the diagnosis, as symptoms should resolve if riboflavin deficiency is the underlying cause. In rare cases, genetic disorders like riboflavin transporter deficiency can prevent the body from absorbing the vitamin correctly, requiring high-dose supplementation.

How is Riboflavin Deficiency Treated?

Treatment involves correcting the nutritional deficit, primarily through dietary changes and supplements. Incorporating foods rich in riboflavin is key, including milk, fortified cereals, lean meats, and eggs. For more severe cases, a healthcare provider may recommend oral supplements, typically in doses of 10–20 mg per day until symptoms resolve. In very rare and severe situations, intramuscular injections may be used. Treating any underlying medical conditions, such as malabsorption disorders, is also crucial.

Comparison of Symptoms and Associated Conditions

To illustrate the diverse impact of riboflavin deficiency, the following table compares the symptoms affecting different parts of the body.


Symptom Category	Specific Manifestations of Riboflavin Deficiency
Oral and Mucosal	Angular cheilitis (cracked mouth corners), cheilosis (swollen, cracked lips), glossitis (magenta, swollen tongue), sore throat, oral mucosa inflammation
Dermatological	Seborrheic dermatitis (greasy, red, scaly rash), especially on the face and genitals; general skin cracking and itching
Ocular	Itchy, red, and burning eyes; light sensitivity (photophobia); corneal neovascularization; cataracts in severe, prolonged cases
General & Neurological	Fatigue and weakness; depression; anemia; liver degeneration; hair loss; reproductive issues

Conclusion

Understanding what are the symptoms of too little riboflavin is essential for identifying and addressing this nutritional deficiency. While it is rare in populations with access to fortified foods, those with restricted diets, malabsorption issues, or certain chronic conditions remain at risk. Recognizing the signs, which primarily affect the mouth, skin, and eyes, allows for prompt treatment through dietary adjustments and supplementation. By addressing the root cause and restoring adequate riboflavin levels, most symptoms are reversible, preventing more severe complications like anemia or cataracts from developing. If you suspect a deficiency, consulting a healthcare professional is crucial for accurate diagnosis and management.

For more detailed, scientific information on riboflavin and its functions, refer to the National Institutes of Health (NIH) fact sheet on riboflavin.

Frequently Asked Questions

The primary cause is inadequate dietary intake of riboflavin-rich foods, which can be exacerbated by malabsorption disorders, chronic diarrhea, and excessive alcohol consumption.

Individuals at a higher risk include people in developing countries with diets low in fortified foods and animal products, chronic alcoholics, the elderly, athletes, pregnant or lactating women, and those with certain genetic disorders or medical conditions like liver disease.

Yes, in some cases, severe and prolonged riboflavin deficiency can contribute to neurological symptoms like depression and, in rare genetic disorders, more serious issues.

Good sources include milk and dairy products, eggs, lean meats, organ meats (like liver), fortified cereals and grains, and green vegetables.

Yes, in most cases, early symptoms are easily reversible with increased dietary intake or supplementation. However, later anatomical changes, such as cataracts, may not be reversed.

Diagnosis is based on clinical symptoms and a patient's history. It can be confirmed by measuring urinary riboflavin excretion or by observing a positive response to riboflavin supplementation.

Yes, severe and prolonged riboflavin deficiency can lead to normochromic-normocytic anemia.