Vitamin B8 Deficiency
Assess whether you present clinical signs of vitamin B8 (biotin) deficiency: hair loss, coarse hair, body hair, red eyes.
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Keeping your balance
Metabolic role of biotin
Biotin is the cofactor for 4 essential carboxylases involved in carbohydrate metabolism (gluconeogenesis), lipid metabolism (fatty acid synthesis), and amino acid metabolism. It is also involved in histone biotinylation, an epigenetic mechanism for regulating gene expression.
Caution with raw egg white
Raw egg white contains avidin, a glycoprotein that binds to biotin with exceptional affinity and renders it unavailable. Cooking denatures avidin and neutralizes this effect. Always consume your eggs cooked to preserve your B8 intake.
Supporting intestinal production
Part of your biotin is produced by your intestinal flora. Maintain your microbiota with fermented foods (yogurt, kefir, sauerkraut) and prebiotic fibres. Repeated antibiotic courses deplete the bacteria that make your biotin. It is your doctor who judges whether they are needed; what you can do is rebuild your flora afterwards, with fermented foods and fibre.
What you can do
Understanding biotin deficiency
Biotin is the cofactor for pyruvate carboxylase (gluconeogenesis), acetyl-CoA carboxylase (fatty acid synthesis), propionyl-CoA carboxylase, and 3-methylcrotonyl-CoA carboxylase. A deficiency leads to accumulation of 3-hydroxyisovaleric acid and impairs keratin synthesis, hence hair loss and fragile nails.
Biological markers to request
Request serum biotin testing to assess circulatory status. The most sensitive marker is urinary 3-hydroxyisovaleric acid: an elevated level reveals functional biotin deficiency, even when serum biotin appears within low normal ranges.
Biotin-rich foods
Prioritize cooked poultry liver (210 mcg/100g), cooked egg yolk (60 mcg/100g), nutritional yeast (50 mcg/100g), walnuts (28 mcg/100g), peanuts, and almonds. Cauliflower, soy, and mushrooms are good complementary plant-based sources.
Biotin supplementation
Supplementation of biotin per day is classically recommended in case of confirmed deficiency. Biotin is well tolerated with no known toxicity at standard doses. Combine it with a B-complex to optimize metabolic synergies between B vitamins. Doses are set with your doctor or your naturopath, all the more so if you already take a medication.
Lifestyle and microbiota
Intestinal bacteria produce a significant portion of biotin. Support your microbiota with fermented foods and prebiotic fibers. Limit antibiotic courses to strict necessity. Always cook your egg whites to neutralize avidin, which traps biotin.
Horsetail for hair and nails
Field horsetail (Equisetum arvense) is rich in organic silica, a structuring mineral for hair and nails. In a 3-month course, it strengthens keratin of hair and nails in synergy with biotin. Choose an extract standardized in organic silicon for better bioavailability.
What you can do
Pathophysiology of biotin deficiency
Biotin is the prosthetic group of 4 human carboxylases. Its deficiency blocks gluconeogenesis (hypoglycemia), fatty acid synthesis (dermatitis), branched-chain amino acid catabolism (organic acidosis), and histone biotinylation (genomic instability). The accumulation of 3-hydroxyisovaleric acid and propionic acid is the direct biochemical reflection of this deficiency.
Priority biological testing
Request serum biotin testing and especially urinary 3-hydroxyisovaleric acid, the most sensitive and earliest marker of biotin deficiency. An elevated level confirms functional deficiency even when serum biotin remains within low normal ranges. Also explore the state of your intestinal microbiota.
Foods to prioritize
Focus on the densest sources: cooked poultry liver (210 mcg/100g), cooked egg yolk (60 mcg/100g), nutritional yeast (50 mcg/100g), walnuts (28 mcg/100g), and peanuts (25 mcg/100g). Avoid raw egg white whose avidin sequesters biotin with exceptional affinity.
Biotin supplementation
Supplementation of biotin per day is recommended to restore reserves. Biotin is water-soluble and has no known toxicity. Combine it with a complete B-complex to respect metabolic synergies. Note: high-dose biotin can interfere with certain thyroid hormone assays; inform your laboratory. Doses are set with your doctor or your naturopath, all the more so if you already take a medication.
Restoring biotin-producing microbiota
Commensal intestinal bacteria synthesize a significant portion of biotin. Restore your flora with targeted probiotics, fermented foods and prebiotic fibres. Repeated antibiotic courses deplete the bacteria that make your biotin. It is your doctor who judges whether they are needed; what you can do is rebuild your flora afterwards, with fermented foods and fibre. Chronic stress and ultra-processed foods alter the microbiota and reduce this endogenous production.
Field horsetail for hair and nails
Field horsetail (Equisetum arvense) is the plant richest in organic silica, a mineral essential for keratin synthesis. In a course of at least 3 months, it strengthens hair and nails in synergy with biotin. Prefer a dry extract standardized in bioavailable organic silicon.
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Related tests
This result is an educational naturopathic self-assessment. It is neither a diagnosis nor medical advice, and it does not replace a consultation. Only a health professional can confirm or rule out a disorder. If symptoms persist, or if you are pregnant, breastfeeding or on any treatment, talk to your doctor before taking any supplement or herbal preparation, and never stop a treatment without medical advice.
How to read this test
Assess whether you present clinical signs of vitamin B8 (biotin) deficiency: hair loss, coarse hair, body hair, red eyes. Free, 5 questions.
Vitamin B8, or biotin (also called vitamin H), is a cofactor for 4 essential carboxylases involved in the metabolism of fatty acids, amino acids, and glucose. It is particularly known for its role in the health of hair, nails, and skin, as it participates in keratin synthesis. Biotin deficiency can occur with regular consumption of raw egg white (which contains avidin, an anti-biotin compound), intestinal dysbiosis, or prolonged antibiotic use.
Strengths
- Rapid identification of clinical signs
- Simple self-assessment test
- Detection of hair, ocular, and cutaneous manifestations linked to biotin deficiency
Limitations
- Does not replace blood testing
- Some signs may have other causes
- Limited sensitivity for subclinical deficiencies