Biotin (Vitamin B7) is a water-soluble B vitamin often recognized for supporting hair, skin, and nail health. As part of the B-complex group, this nutrient helps the body convert food into usable energy. During pregnancy, a time of rapid growth and increased metabolic demands, the focus shifts from cosmetic benefits to the vitamin’s profound biological functions. Biotin is required for both maternal health and proper fetal development, making the question of supplementation important.
Biotin’s Essential Role During Pregnancy
Biotin functions as a coenzyme for several carboxylase enzymes that drive fundamental metabolic processes. These biotin-dependent enzymes are directly involved in metabolizing carbohydrates, fats, and proteins, ensuring efficient energy production. Since pregnancy significantly heightens the body’s metabolism to support the growing fetus, the proper function of these enzymes is especially important.
The vitamin’s involvement in cell growth and gene regulation is particularly relevant for the developing baby. Biotin is required for synthesizing essential fatty acids and amino acids, which are the foundational building blocks for new cells and tissues. Because fetal development involves rapid cell division, an insufficient maternal supply can potentially lead to issues, as demonstrated in animal models where biotin deficiency is teratogenic.
Research suggests that a marginal biotin deficiency can occur even in normal human pregnancies, though the exact biological reason is not fully understood. This potential for reduced biotin status during gestation underscores the need for pregnant individuals to maintain an adequate intake. Biotin supports the formation of the nervous system and aids in the proper formation of the brain and spinal cord, potentially reducing the risk of developmental issues.
Dietary Sources Versus Supplementation
Most people can meet their biotin requirements through a balanced diet, as the vitamin is naturally present in a variety of common foods. Excellent dietary sources include cooked eggs (especially the yolk, which contains about 10 micrograms per egg), organ meats like beef liver, nuts and seeds such as almonds and sunflower seeds, and certain vegetables like sweet potatoes and spinach.
The potential for marginal deficiency during pregnancy means that a typical diet may not provide enough for the increased demands of gestation. For this reason, many healthcare providers recommend a prenatal vitamin containing biotin to ensure a consistent, reliable intake. Prenatal supplements are designed to cover this increased nutritional need and typically contain the recommended amount.
If diet alone is insufficient, or if a pregnant individual has a condition affecting nutrient absorption, a healthcare provider might suggest a targeted supplement. Note that a protein in raw egg whites, called avidin, can bind to biotin and prevent its absorption. Cooking denatures this protein, however, making cooked eggs a safe and rich source.
Safety Concerns and Recommended Intake
Biotin is generally considered safe when consumed at recommended intake levels because it is water-soluble, and any excess is typically excreted through urine. The Adequate Intake (AI) level recommended for pregnant individuals is 30 micrograms (mcg) per day, which is the same as for non-pregnant adults. For breastfeeding women, the recommendation slightly increases to 35 mcg daily.
The primary safety concern is not toxicity, as no tolerable upper intake level has been established, but rather the use of high-dose supplements. High-dose biotin, often found in “hair, skin, and nail” supplements far exceeding 30 mcg, can interfere with common laboratory blood tests. This interference occurs because many lab assays use biotin-streptavidin technology to measure various substances, including thyroid hormones and troponin.
High levels of supplemental biotin can cause falsely high or falsely low results in these tests, potentially leading to misdiagnosis or incorrect treatment. During pregnancy, this interference is concerning for thyroid function tests and human chorionic gonadotropin (hCG) tests, which monitor the pregnancy and diagnose issues like ectopic pregnancy or miscarriage. Therefore, it is advised to only take biotin at the recommended levels found in prenatal vitamins and to always inform a healthcare provider about all supplements before any scheduled blood work.