Biotin, often referred to as vitamin B7 or vitamin H, is a water-soluble B-vitamin that plays many roles in the body. This article clarifies the relationship between biotin and cancer, addressing common questions based on current scientific understanding.
Understanding Biotin’s Role
Biotin is a coenzyme involved in various metabolic processes, including the breakdown of fats, carbohydrates, and proteins. It acts as a cofactor for several carboxylase enzymes, which are necessary for reactions in gluconeogenesis (glucose production), fatty acid synthesis, and amino acid catabolism. Biotin also influences gene regulation and cellular signaling, affecting cell growth and development.
The human body obtains biotin through dietary sources and, to some extent, from gut bacteria. Foods rich in biotin include eggs, nuts, seeds, fish like salmon, meat, dairy products, and certain vegetables such as spinach and sweet potatoes. Dietary intake is considered the primary source.
Biotin and Cancer Detection Accuracy
High doses of biotin can interfere with the accuracy of certain laboratory tests, particularly immunoassays. These tests are used for diagnosing and monitoring various conditions, including some cancer markers, hormones, and cardiac function biomarkers. The interference can lead to either falsely decreased or falsely increased results, depending on the specific test and its design.
The mechanism of interference involves the biotin-streptavidin technology used in these immunoassays. Biotin has a strong affinity for streptavidin, a protein used in many assays to capture or detect analytes. When high levels of supplemental biotin are present in a patient’s blood sample, this excess biotin can saturate streptavidin binding sites, preventing the detection of the antibody-antigen complex. For instance, in a sandwich immunoassay, excess biotin can lead to falsely low results, while in a competitive immunoassay, it can cause falsely high results.
Examples of tests that can be affected include certain tumor markers such as Cancer Antigen 125 (CA 125), Carcinoembryonic Antigen (CEA), and Prostate Specific Antigen (PSA). Thyroid function tests can also be impacted, potentially leading to a misdiagnosis of hyperthyroidism. Individuals should inform their healthcare providers about all biotin supplementation, especially high-dose products, before any blood tests, as this allows for proper interpretation of results. Patients are advised to stop biotin supplementation for at least 48 hours before blood collection for such tests.
Biotin’s Influence on Cancer Development and Progression
There is no evidence that normal dietary biotin intake causes cancer. Research into biotin’s relationship with cancer development and progression is complex. Studies have shown that some malignant tumors can have higher biotin content compared to corresponding adult tissue. This suggests that cancer cells may have increased biotin requirements to sustain their proliferation.
This increased requirement has led to investigations into targeting biotin metabolism in cancer cells. Research explores compounds that compete with biotin or inhibit enzymes like holocarboxylase synthetase (HLCS) to impair tumor growth. High HLCS expression has been associated with glioblastoma, a type of brain cancer, and its gene silencing has reduced tumorigenicity in mouse models. This research explores therapeutic avenues to disrupt biotin’s role in cancer cell metabolism, not suggesting biotin causes cancer or that supplementation is a treatment.
Biotin supplementation is not a recognized treatment for cancer and should not be used as such. The idea that biotin supplementation might “feed” cancer cells is an oversimplification and is not supported by clinical evidence for typical supplementation levels. While some studies suggest biotin deficiency might activate survival pathways in certain cancer cells, potentially enhancing resistance to antineoplastic agents, these are laboratory findings and do not translate to a recommendation for biotin supplementation in cancer treatment. Most biotin-based anticancer drugs remain in preclinical stages, due to the need for more preliminary research data and evidence of efficacy in human clinical trials.
Important Considerations for Cancer Patients
Individuals undergoing cancer treatment should discuss all supplements, including biotin, with their oncology team or healthcare provider before use. Supplements can interact with cancer treatments or affect the accuracy of laboratory tests. While biotin is considered safe, high doses can lead to incorrect results on certain lab tests, potentially hindering diagnosis or obscuring treatment response.
In some cases, cancer patients might experience biotin deficiency. Such deficiencies can be managed under medical supervision through targeted supplementation. Any supplementation should be carefully considered and directed by a healthcare professional to avoid potential complications, especially diagnostic test interference. Supplements should never replace prescribed cancer therapies; their role in cancer care is supportive, not curative.