What Vitamin Deficiency Causes Cuts in the Corner of the Mouth?

December 26, 2025 •

4 min read

According to several medical sources, angular cheilitis—the medical term for painful, cracked sores at the corners of the mouth—is often linked to nutritional deficiencies. This condition is not just a sign of dry skin, but can indicate an underlying health issue related to a lack of specific vitamins and minerals, most notably riboflavin.

Quick Summary

This article explains how certain nutritional deficiencies, primarily involving riboflavin and iron, can cause angular cheilitis, and outlines associated symptoms, other contributing factors, and treatment strategies.

Key Points

Riboflavin is Key: Riboflavin (Vitamin B2) deficiency is the most common vitamin link to angular cheilitis, causing painful cracks at the mouth corners.
Iron and B12 are also culprits: Deficiencies in iron and vitamin B12 also contribute significantly to the condition, impacting tissue repair and oxygen transport.
Infection is a common complication: The cracked skin is highly susceptible to secondary fungal or bacterial infections, most commonly Candida yeast.
Other causes exist: Beyond nutrition, causes include excessive saliva, ill-fitting dentures, lip-licking, and certain medications.
Treatment is multifaceted: Effective treatment involves correcting the nutritional deficiency, managing any secondary infections with topical creams, and addressing local irritants.

The Primary Suspect: Riboflavin (Vitamin B2) Deficiency

Riboflavin, or Vitamin B2, is consistently identified as a key nutritional factor in the development of angular cheilitis. This water-soluble vitamin plays a vital role in maintaining healthy skin, hair, and mucous membranes. A lack of riboflavin directly impacts the skin's integrity, particularly in delicate areas like the corners of the mouth.

Symptoms of ariboflavinosis

A deficiency in riboflavin, known as ariboflavinosis, presents with several tell-tale signs, often including:

Painful cracks (fissures) in the corners of the mouth.
Magenta-colored tongue.
Sore throat and swelling of the mouth's mucous membranes.
Dermatitis (greasy, scaly patches) around the nose and genitals.
Changes to the cornea of the eye, causing light sensitivity and blurred vision in severe cases.

Sources of Riboflavin

For those with a deficiency, increasing riboflavin intake is crucial. Good dietary sources include:

Dairy products: Milk, cheese, yogurt.
Meat: Lean meat, eggs, and liver.
Vegetables: Leafy greens like spinach.
Legumes and nuts: Almonds.
Grains: Fortified cereals.

Other Nutritional Culprits: Iron, B12, and Zinc

While riboflavin is a primary cause, other nutritional deficiencies can also contribute to or trigger angular cheilitis. These often occur concurrently, as poor diet or malabsorption can lead to multiple issues.

Iron Deficiency

Iron deficiency, which can lead to anemia, impairs the delivery of oxygen to the body's tissues, including the delicate skin at the mouth's corners. This slows healing and increases vulnerability to inflammation and cracking. Symptoms of iron deficiency anemia can also include fatigue, pale skin, and brittle nails. Correcting the underlying iron deficiency is necessary for permanent relief.

Vitamin B12 and Folate (B9) Deficiencies

These B vitamins are essential for cell repair and are frequently deficient in people with poor nutritional intake or malabsorption issues. A lack of Vitamin B12, often found in animal products, can lead to painful mouth sores, glossitis (tongue inflammation), and angular cheilitis. Vegetarians, vegans, and those with certain gastrointestinal disorders are at higher risk.

Zinc Deficiency

Zinc is a vital mineral for immune function and tissue repair. A deficiency can impair wound healing and make skin more susceptible to breakdown, leading to angular cheilitis. Zinc deficiency may also cause dermatitis and hair loss.

Comparison of Angular Cheilitis Causes

This table highlights the differences between nutritionally-induced and other common causes of angular cheilitis.


Feature	Nutritional Deficiency Cause	Other Common Causes (Non-Nutritional)
Underlying Mechanism	Lack of essential nutrients (B vitamins, iron, zinc) impairs cell repair and skin health.	Environmental factors, moisture buildup, and infections irritate the skin.
Key Trigger	Poor diet, malabsorption issues (e.g., Crohn's), or underlying health problems affecting nutrient uptake.	Lip-licking habits, ill-fitting dentures, drooping facial skin, or fungal/bacterial infections.
Associated Symptoms	Often accompanied by other deficiency signs (fatigue, dermatitis, pale tongue).	Symptoms are often localized to the mouth corners, possibly with signs of yeast or bacterial infection.
Primary Treatment Focus	Dietary changes and supplementation to correct nutrient levels.	Topical treatments (antifungal/antibacterial creams) and addressing local irritants.

How to Manage and Prevent Cracked Mouth Corners

Beyond correcting nutritional deficiencies, several steps can help manage symptoms and prevent recurrence.

Topical Treatments and Hygiene

Keep the area moisturized: Use unscented, unflavored lip balms or petroleum jelly to create a protective barrier. Avoid licking your lips, which only worsens the dryness.
Address secondary infections: Because the open cracks are prone to infection by Candida yeast or Staphylococcus bacteria, a healthcare provider may prescribe topical antifungal or antibiotic creams.
Maintain oral hygiene: Keep your mouth and any dental hardware, like dentures, clean to reduce microbial buildup.

Dietary Adjustments and Supplementation

Increase intake of nutrient-rich foods: Eat a balanced diet with plenty of fruits, vegetables, lean meats, and fortified grains to get adequate vitamins and minerals.
Consider supplements: If dietary intake is insufficient or an underlying absorption issue exists, a doctor may recommend a B-complex supplement, iron tablets, or zinc supplements.

Address Mechanical Irritants

Check denture fit: Ensure dentures fit correctly to prevent saliva from pooling at the mouth's corners.
Manage saliva: If excessive drooling is a problem, use a barrier cream to protect the skin.

Conclusion

Cuts at the corner of the mouth, known as angular cheilitis, can be a painful and frustrating condition. While often mistaken for simple chapped lips, they frequently signal an underlying nutritional deficiency, most notably in riboflavin (Vitamin B2), iron, or other B vitamins. While topical treatments can soothe symptoms, addressing the root cause through dietary changes or supplementation is essential for preventing recurrence. Always consult a healthcare professional for an accurate diagnosis and treatment plan, as other factors like infection or dental issues may also be at play.

For more detailed information on angular cheilitis, visit the Cleveland Clinic's article on the topic.

Frequently Asked Questions

No, angular cheilitis is not contagious. However, if a secondary infection, such as herpes simplex, is the cause, that specific virus can be transmissible.

Foods rich in riboflavin include dairy products (milk, cheese), eggs, lean meat, fortified cereals, and green leafy vegetables.

Yes, an iron deficiency can be a direct cause of angular cheilitis. It impairs oxygen supply to tissues, hindering the healing process and making the skin more fragile.

Treatment involves dietary changes to increase nutrient intake and potentially taking supplements under a doctor's supervision. Topical creams may be used to address any concurrent infection.

A doctor can help determine the cause. They may run lab tests for nutrient levels, test for infections, and evaluate contributing factors like dental hardware or saliva issues.

With proper treatment, angular cheilitis typically resolves within a couple of weeks. However, it may recur if the underlying cause, such as a nutritional deficiency, is not fully addressed.

Zinc is important for skin repair and immune function. A zinc deficiency can hinder wound healing and contribute to the inflammation and scaling seen in angular cheilitis.