Does Biotin Deplete Vitamin B5? Understanding the Nutrient Balance

December 19, 2025 •

4 min read

Over 10,000 Americans are hospitalized annually due to supplement interactions and side effects, and some research suggests that high-dose biotin supplements can potentially interfere with the absorption of vitamin B5. This competition can lead to a relative deficiency of vitamin B5, which is an important consideration for supplement users.

Quick Summary

High-dose biotin can create a nutrient imbalance by competing with vitamin B5 for absorption, potentially causing a functional deficiency of pantothenic acid. This imbalance is sometimes linked to dermatological issues like acne, although the direct evidence is debated.

Key Points

High-Dose Supplementation: Excessive biotin intake can outcompete vitamin B5 for absorption in the gut, leading to a functional vitamin B5 deficiency.
Acne Connection: The theoretical link between biotin supplements and acne flare-ups is often attributed to the resulting vitamin B5 imbalance, which can disrupt skin oil production.
Absorption Mechanism: Both biotin (B7) and pantothenic acid (B5) utilize the same sodium-dependent multivitamin transporter (SMVT) for intestinal and cellular uptake.
Dietary Intake is Key: For the majority of healthy people, a varied diet provides adequate amounts of both biotin and pantothenic acid, making high-dose supplements generally unnecessary.
Interference with Lab Tests: High biotin intake can interfere with certain lab tests, including thyroid and troponin tests, leading to inaccurate results and potential misdiagnosis.
Low Toxicity, Potential Side Effects: While biotin toxicity is rare because excess is excreted in urine, the competition with B5 and other factors can still cause side effects like digestive issues and acne.

The Surprising Link Between Biotin and Vitamin B5

It is a common misconception that taking biotin, also known as vitamin B7, will automatically lead to better hair, skin, and nails. While it is an essential nutrient for these functions, the practice of taking high-dose supplements can have unintended consequences. Specifically, there is evidence suggesting that a significant intake of biotin can interfere with the body's ability to absorb another vital B vitamin, pantothenic acid, or vitamin B5. Both biotin and vitamin B5 use the same intestinal transport system for absorption. When a person consumes a very high amount of biotin, the sheer volume can saturate the transport system, effectively outcompeting the much smaller amount of vitamin B5 typically present. This competition can create a functional or relative deficiency of B5, despite sufficient dietary intake.

The Absorption Mechanism and Nutritional Science

To understand this interaction, it's helpful to look at the sodium-dependent multivitamin transporter (SMVT), the protein responsible for moving both biotin and pantothenic acid across intestinal and cellular membranes. Under normal circumstances, both vitamins are absorbed efficiently. However, in the context of high-dose supplementation, such as the 5,000 to 10,000 mcg doses often marketed for cosmetic benefits, the balance is heavily tipped towards biotin. Research, including some studies on intestinal cells, has observed this competitive inhibition. This means that while high-dose biotin is largely non-toxic and excess amounts are typically excreted in the urine, it can still create a significant internal imbalance. The physiological effects of this competition are a point of discussion among nutritional scientists and dermatologists.

The Biotin-Acne Connection

One of the most frequently discussed side effects of high-dose biotin is the potential for acne breakouts. This phenomenon, while anecdotally reported, is theorized to be a direct result of the biotin-B5 competition. Vitamin B5 is crucial for maintaining the skin's barrier function and regulating oil production in the sebaceous glands. A relative deficiency of B5 could disrupt this function, leading to a cascade of events: increased sebum production, clogged pores, and subsequent acne flares. For individuals already prone to acne, this could exacerbate a pre-existing condition. Some dermatologists and nutrition experts suggest that the link lies more with the potential B5 deficiency rather than biotin itself. Interestingly, some studies have explored the use of B5 for treating acne, suggesting that a proper balance is key for skin health.

How to Mitigate the Risk of Nutrient Depletion

For individuals concerned about this interaction, there are several steps to take. First, consider whether high-dose supplementation is truly necessary. For most healthy people, biotin deficiency is rare, and the recommended daily intake (around 30 mcg for adults) is easily met through a balanced diet rich in foods like eggs, nuts, and legumes. If you choose to supplement, sticking to lower doses may reduce the risk of competition. Another strategy is to space out the intake of biotin and pantothenic acid if taking them separately. If taking a B-complex supplement, ensure the vitamins are properly balanced. For those experiencing side effects like acne, reverting to a food-first approach or a lower dose is often recommended.

Comparison Table: Biotin vs. Pantothenic Acid


Feature	Biotin (Vitamin B7)	Pantothenic Acid (Vitamin B5)
Primary Role	Metabolism of fats, carbohydrates, and proteins; supports healthy hair, skin, and nails.	Component of Coenzyme A (CoA); vital for energy metabolism, hormone synthesis, and healthy skin.
Absorption	Absorbed via the sodium-dependent multivitamin transporter (SMVT) in the small intestine.	Absorbed via the same SMVT as biotin, creating competition at high doses.
Recommended Daily Intake (Adults)	30 mcg (Adequate Intake)	5 mg (Adequate Intake)
Deficiency Symptoms	Thinning hair, skin rashes, brittle nails, neurological issues.	Fatigue, insomnia, numbness/tingling, skin issues, muscle cramps.
Common Supplement Dose	Often sold in high doses (e.g., 5,000-10,000 mcg) for hair/nail health.	Less common as a standalone supplement, often in B-complexes.

Sources of Biotin and Vitamin B5

A diversified diet remains the best way to ensure adequate intake of all B vitamins without the risks associated with excessive supplementation. Biotin is abundant in cooked eggs, organ meats, seeds, nuts, and certain vegetables like sweet potatoes and cauliflower. Vitamin B5 is widely distributed in foods, with good sources including eggs, meat, whole grains, avocado, and dairy. Since both are water-soluble, excess amounts are not stored by the body, so consistent intake from dietary sources is ideal.

The Takeaway: Is Biotin to Blame?

The relationship between biotin and vitamin B5 illustrates a critical concept in nutrition: balance is paramount. While biotin itself may not be inherently harmful at high doses, its interaction with the absorption of other key nutrients can lead to secondary effects. For most individuals, the perceived benefits of high-dose biotin for cosmetic purposes are largely unproven by robust scientific evidence. The best course of action is to obtain these vitamins from a varied, nutritious diet. If you are considering supplementation, understanding the potential for competition and consulting a healthcare professional is wise, especially if you have concerns about skin health. For further information, the NIH Office of Dietary Supplements provides detailed factsheets on both biotin and pantothenic acid.

Conclusion

In summary, while biotin does not inherently destroy or "deplete" vitamin B5 from the body in a direct chemical sense, high-dose biotin supplementation can indirectly cause a relative or functional deficiency of vitamin B5 by overwhelming the shared intestinal absorption pathway. This competition is a plausible mechanism behind reported side effects like acne. For most people, a balanced diet is sufficient for healthy biotin and pantothenic acid levels, making high-dose supplementation unnecessary and potentially counterproductive to maintaining a balanced nutritional state. By prioritizing whole-food sources and considering moderation in supplementation, individuals can support overall health and mitigate the risk of unintended nutrient imbalances.

Frequently Asked Questions

Yes, some anecdotal and theoretical evidence suggests that high-dose biotin supplements can lead to acne breakouts. This is thought to be caused by the competition for absorption between biotin and vitamin B5, which is essential for healthy skin function.

To minimize the risk of a vitamin B5 deficiency, consider obtaining your nutrients from a balanced diet rather than high-dose supplements. If you do supplement, choose a lower dose or take biotin and vitamin B5 at different times to reduce absorption competition.

Yes, both biotin (B7) and pantothenic acid (B5) are absorbed using the same sodium-dependent multivitamin transporter (SMVT), which can become saturated when one vitamin is consumed in very high amounts.

While there is no established upper intake level (UL) for biotin, many supplements contain doses far exceeding the recommended 30 mcg Adequate Intake (AI). Doses over 2,500 mcg are considered high and are more likely to cause absorption interference and other side effects.

Excellent food sources for both include eggs, organ meats, nuts, seeds, and legumes. Pantothenic acid is also found in meat, whole grains, and vegetables, while biotin is also in sweet potatoes and bananas.

Yes, it is crucial to inform your doctor if you are taking biotin supplements, as they can interfere with various laboratory tests, including those for thyroid function and heart health. You may need to stop taking it for a certain period before the test.

Since biotin is a water-soluble vitamin, any excess not used by the body is simply excreted in the urine. This is why high doses don't typically lead to toxicity, but can still cause other issues like nutrient competition.