Biotin or Vitamin B7

Biotin, also known as vitamin B7 or vitamin H (from the German words Haar and Haut, meaning hair and skin), is a water-soluble B vitamin essential for various physiological processes. This vitamin plays a critical role in energy metabolism, supporting healthy hair, skin, and nails.

What Is Biotin?

Biotin belongs to the B-vitamin complex and is involved in the metabolism of carbohydrates, fats, and proteins. It acts as a coenzyme for carboxylase enzymes, which help in the synthesis of fatty acids, gluconeogenesis (glucose production from non-carbohydrate sources), and the breakdown of amino acids. Although the body needs only small amounts of biotin, its impact on health is significant.

Food Sources of Biotin

Biotin is found in various foods, particularly those rich in protein and healthy fats. Here are some of the best dietary sources:

1. Egg Yolks

   • Rich in biotin, but avoid raw egg whites as they contain avidin, a protein that binds biotin and inhibits its absorption.
   • Biotin Content: ~10 micrograms per egg.

2. Organ Meats (Liver and Kidney)

   • These are among the highest sources of biotin.
   • Biotin Content: Beef liver provides ~30-35 micrograms per 3-ounce serving.

3. Nuts and Seeds

   • Almonds, walnuts, sunflower seeds, and peanuts are excellent sources.
   • Biotin Content: ~1.5-6 micrograms per 28-gram serving.

4. Legumes

   • Lentils, soybeans, and peas are biotin-rich and also high in protein and fiber.
   • Biotin Content: ~1.5-5 micrograms per serving.

5. Whole Grains

   • Whole wheat bread and oats contain biotin, though processing can reduce its levels.
   • Biotin Content: ~0.2-0.4 micrograms per serving.

6. Dairy Products

   • Milk, cheese, and yogurt provide moderate amounts.
   • Biotin Content: ~0.3-0.4 micrograms per serving.

7. Fruits and Vegetables

   • Avocados, sweet potatoes, spinach, and broccoli are good plant-based sources.
   • Biotin Content: ~0.2-2 micrograms per serving.

8. Fish

   • Salmon and tuna are excellent sources of biotin and omega-3 fatty acids.
   • Biotin Content: ~4-5 micrograms per serving.

Benefits of Biotin

Biotin is vital for several physiological and biochemical processes. Here are the key benefits:

1. Supports Hair Health

Biotin is widely recognized for promoting healthy hair growth and preventing hair thinning. It strengthens hair shafts and minimizes breakage.

• Evidence: A study published in The Journal of Clinical and Aesthetic Dermatology found that biotin supplementation improved hair growth in individuals with thinning hair.

2. Enhances Skin Health

Biotin plays a role in maintaining the skin's barrier function, reducing dryness, and preventing conditions like dermatitis.

• Evidence: Research in Dermatology Reports highlights that biotin deficiency can lead to scaly skin rashes.

3. Strengthens Nails

Biotin helps improve nail thickness and reduces brittleness, promoting healthy nail growth.

• Evidence: A study in Cutis found that daily biotin supplementation increased nail thickness by 25%.

4. Supports Energy Metabolism

Biotin aids in converting carbohydrates, fats, and proteins into usable energy, making it essential for maintaining physical and mental energy levels.

• Mechanism: It functions as a coenzyme for carboxylases, critical in metabolic pathways.

5. Regulates Blood Sugar Levels

Biotin may help manage blood sugar by improving glucose metabolism.

• Evidence: Studies in diabetic patients have shown that biotin supplementation can lower fasting blood glucose levels.

6. Promotes Fetal Development

Biotin is essential during pregnancy as it supports embryonic growth and reduces the risk of congenital disabilities. Pregnant women often require higher biotin levels.

• Recommendation: The National Institutes of Health recommends 30 micrograms/day for pregnant women.

Biotin Deficiency: Causes and Symptoms

Although biotin deficiency is rare due to its presence in many foods and production by gut bacteria, certain conditions and habits can increase the risk:

Causes of Biotin Deficiency

1. Dietary Insufficiency

   • Low intake of biotin-rich foods.

2. Chronic Alcoholism

   • Alcohol interferes with biotin absorption and utilization.

3. Prolonged Antibiotic Use

   • Antibiotics can disrupt gut microbiota, reducing biotin synthesis.

4. Consuming Raw Egg Whites

   • Avidin in raw egg whites binds to biotin and prevents absorption.

5. Pregnancy

   • Increased demand for biotin during fetal development.

Symptoms of Deficiency

• Thinning hair or hair loss.
• Scaly red rashes, particularly around the eyes, nose, and mouth.
• Brittle nails.
• Fatigue and lethargy.
• Depression, hallucinations, or cognitive impairments.
• Muscle pain and weakness.
• Tingling sensations in the extremities.

Diseases Associated with Biotin Deficiency

If left untreated, biotin deficiency can lead to severe health issues:

1. Dermatitis and Alopecia
   Prolonged deficiency causes dermatitis (skin inflammation) and hair loss.

2. Neurological Disorders
   Biotin deficiency can result in mood disturbances, seizures, and developmental delays in infants.

3. Biotinidase Deficiency
   A genetic disorder where the body cannot recycle biotin effectively, leading to neurological and dermatological symptoms.
   • Treatment: Lifelong biotin supplementation.

Recommended Daily Intake of Biotin

The National Institutes of Health (NIH) provides the following Adequate Intake (AI) levels for biotin:

• Infants (0-12 months): 5-6 micrograms/day.
• Children (1-13 years): 8-20 micrograms/day.
• Adults (14 years and older): 30 micrograms/day.
• Pregnant Women: 30 micrograms/day.
• Breastfeeding Women: 35 micrograms/day.

Biotin Supplementation: Is It Necessary?

Biotin supplements are widely available in tablets, capsules, and gummies. Supplementation may be beneficial for individuals with:

1. Deficiency: Diagnosed biotin deficiency due to genetic disorders or malabsorption issues.
2. Hair and Nail Problems: To address brittleness and thinning.
3. Pregnancy: To meet increased demands during fetal development.

Caution: Excessive biotin intake (over 200 micrograms/day) can interfere with laboratory tests, leading to inaccurate results for thyroid, heart, or hormone levels.

Conclusion

Biotin, though required in small amounts, plays a crucial role in maintaining hair, skin, nails, and overall metabolic health. Including biotin-rich foods like eggs, nuts, and vegetables in your diet is essential to prevent deficiency and promote well-being. While supplementation can be helpful for specific conditions, a balanced diet is typically sufficient for meeting daily needs. By prioritizing biotin and other nutrients, you can support a healthier, more vibrant life.

References

1. Zempleni, J., et al. (2008). Biotin and biotinidase deficiency. Expert Review of Endocrinology & Metabolism.
2. Flohé, L., & Gässler, K. (2012). Role of biotin in cellular metabolism. Archives of Biochemistry and Biophysics.
3. Staggs, C. G., et al. (2004). Biotin supplementation improves nail strength: Results from an open-label trial. Cutis.
4. Mock, D. M., et al. (2002). Biotin deficiency: Occurrence and implications. Nutrition Reviews.
5. The National Institutes of Health Office of Dietary Supplements. (2023). Biotin Fact Sheet for Health Professionals