What Causes Low Biotin Levels in the Body?

October 13, 2025 •

4 min read

According to research, while overt biotin deficiency is rare in the general population, marginalized deficiencies are more common, particularly in pregnant women. Understanding what causes low biotin levels in the body is crucial for identifying risk factors and preventing health complications.

Quick Summary

Several factors, including inherited disorders, medication use, dietary habits, and certain medical conditions, can lead to depleted biotin levels. Prompt identification of these causes is key to effective management and preventing potential health issues.

Key Points

Genetic Factors: Inherited disorders like biotinidase deficiency can prevent the body from recycling biotin, leading to lifelong treatment needs.
Raw Egg Whites: Excessive consumption of raw egg whites can cause biotin deficiency because the protein avidin binds to biotin, blocking its absorption.
Medication Interactions: Long-term use of certain anticonvulsant and antibiotic drugs can interfere with biotin absorption and metabolism.
Chronic Alcohol Use: High alcohol intake impairs intestinal biotin uptake, making chronic alcoholics a high-risk group for deficiency.
Pregnancy and Lactation: The body's increased metabolic demand during pregnancy and breastfeeding can lead to marginal biotin deficiency.
Malabsorption Issues: Conditions affecting the digestive system, such as inflammatory bowel disease, can hinder the absorption of dietary biotin.
Poor Dietary Habits: An inadequate diet lacking biotin-rich foods is a risk factor, especially for those on prolonged intravenous feeding.

Introduction to Biotin and Deficiency

Biotin, also known as vitamin B7, is a water-soluble B vitamin that plays a vital role in various metabolic functions, including the metabolism of fats, carbohydrates, and proteins. The body cannot produce biotin on its own, so it must be obtained from dietary sources, and it is also synthesized by gut bacteria. While a severe biotin deficiency is rare in individuals with a balanced diet, certain factors can disrupt its absorption, metabolism, or utilization, leading to low biotin levels.

Inherited Genetic Disorders

Genetic conditions are one of the most significant causes of severe biotin deficiency, often presenting in infancy. These disorders impair the body's ability to properly utilize or recycle the vitamin.

Biotinidase Deficiency (BTD)

This is a rare, inherited metabolic disorder where the body cannot recycle biotin. The enzyme biotinidase is responsible for removing biotin from proteins so it can be reused. In individuals with BTD, this process is impaired, leading to a shortage of free biotin.

Profound BTD: Characterized by less than 10% of normal biotinidase activity, it can cause severe symptoms like seizures, hypotonia, and developmental delays.
Partial BTD: With 10% to 30% of normal activity, symptoms may be milder and only appear during periods of physiological stress like illness.

Holocarboxylase Synthetase (HCS) Deficiency

Another rare genetic disorder, HCS deficiency prevents the proper binding of biotin to carboxylase enzymes, disrupting their function. Symptoms typically appear in newborns and can include lethargy, seizures, and feeding difficulties.

Dietary and Lifestyle Factors

Beyond genetics, everyday habits and nutritional intake play a large part in maintaining adequate biotin levels.

Excessive Raw Egg White Consumption: Raw egg whites contain a protein called avidin, which binds strongly to biotin and prevents its absorption in the digestive tract. This binding is irreversible unless the eggs are cooked, which denatures the avidin.
Chronic Alcoholism: Long-term, excessive alcohol consumption can inhibit the intestinal absorption of biotin by reducing the expression of a key transporter protein. Chronic alcohol use is a notable risk factor for biotin deficiency.
Poor Diet and Undernutrition: Individuals on a restricted or poor diet that lacks sufficient biotin-rich foods (e.g., eggs, nuts, organ meats, legumes) are at risk of deficiency. This is especially relevant for those on prolonged parenteral (intravenous) nutrition without adequate biotin supplementation.
Smoking: Some studies suggest that smoking may accelerate biotin catabolism, potentially increasing the risk of deficiency.

Medical Conditions and Medications

Certain health issues and pharmaceutical drugs can disrupt biotin absorption and metabolism.

Pregnancy and Lactation: Up to half of pregnant women may develop a marginal biotin deficiency due to increased metabolic demands. Requirements also increase during lactation.
Gastrointestinal Disorders: Conditions that affect nutrient absorption in the gut, such as inflammatory bowel disease (Crohn's, celiac disease), can lead to malabsorption of biotin.
Chronic Antibiotic Use: Prolonged use of antibiotics can interfere with the balance of intestinal flora, which naturally produce biotin.
Anti-Seizure Medications: Long-term use of certain anticonvulsants (phenytoin, carbamazepine, phenobarbital) can increase biotin catabolism and inhibit its absorption.
Isotretinoin: This acne medication has also been linked to potential interference with biotin metabolism.

Comparison of Biotin Deficiency Causes


Cause Category	Example	Primary Mechanism	Onset	Treatment	Reversibility
Genetic	Biotinidase Deficiency	Inability to recycle biotin	Early infancy	Lifelong biotin supplementation	Excellent if treated early; irreversible damage if delayed.
Dietary	Raw Egg Whites	Avidin protein binds and prevents absorption	After excessive consumption	Cease eating raw eggs, biotin supplementation	Reversible.
Lifestyle	Chronic Alcoholism	Impaired intestinal uptake	Long-term use	Reduce alcohol, supplementation	Reversible with lifestyle change and supplements.
Medication	Anti-Seizure Drugs	Increased catabolism and reduced absorption	Over time with medication use	Biotin supplementation, drug modification if possible	Reversible with treatment.
Physiological	Pregnancy	Increased metabolic demand	During pregnancy	Increased dietary intake or supplementation	Reversible after pregnancy/lactation.

Understanding the Symptoms

Recognizing the signs of low biotin is key to early intervention. Symptoms typically develop gradually and can affect multiple body systems. Common symptoms include:

Dermatological: Thinning hair (alopecia), scaly red rash around body openings (eyes, nose, mouth), brittle nails.
Neurological: Depression, lethargy, hallucinations, numbness or tingling in extremities (paresthesia), and muscle pain.
Other Signs: Conjunctivitis (red eyes), poor appetite, and fatigue.

In infants with genetic deficiencies, severe symptoms can include developmental delays, seizures, and hypotonia (weak muscle tone).

Conclusion

While a severe biotin deficiency is rare, several underlying factors can lead to low biotin levels. Inherited genetic conditions like biotinidase deficiency represent a permanent cause requiring lifelong management. Other causes, such as dietary issues from consuming excessive raw eggs, chronic alcoholism, or prolonged medication use, are often reversible with targeted changes. For at-risk individuals, being aware of the causes and symptoms can lead to early detection and prevent potential complications. Consulting a healthcare provider is the best course of action to diagnose and treat a biotin deficiency effectively. To learn more about biotin's functions and rich food sources, refer to the National Institutes of Health Office of Dietary Supplements.

Frequently Asked Questions

The most common cause of biotin deficiency is dietary inadequacy, especially combined with other risk factors like chronic alcoholism or medication use. However, genetic disorders like biotinidase deficiency are the most severe and common cause in infants detected by newborn screening.

Yes, taking high doses of biotin supplements can cause significant interference with certain lab tests, including those for thyroid hormones and troponin, leading to false-positive or false-negative results. It is important to inform your doctor if you are taking biotin supplements before any lab work.

Marginal biotin deficiency is common during pregnancy, and while overt deficiency is rare, some healthcare providers may recommend supplements to ensure adequate intake. Always consult a healthcare professional before starting any supplement during pregnancy.

The speed of recovery depends on the underlying cause. For dietary deficiencies, symptoms can resolve quickly with supplementation and diet changes. For genetic conditions like biotinidase deficiency, lifelong supplementation is required to manage the condition and prevent symptoms.

Biotin is found in a variety of foods, including cooked egg yolks, liver, legumes (like peanuts and soybeans), nuts, seeds, and sweet potatoes.

While biotin is available in both plant and animal-based foods, vegetarians and vegans following a restricted diet may be at a higher risk of dietary insufficiency if they do not consume enough biotin-rich plant sources like legumes, nuts, and seeds.

If genetic biotinidase deficiency is left untreated, it can lead to irreversible complications, including hearing loss, optic atrophy, and developmental delays. Early diagnosis and lifelong treatment are crucial to prevent such long-term damage.