Popular hair growth supplement can mess with cancer treatment, doc warns

B-ware of B7?

As if battling cancer wasn’t difficult enough, many patients lose their hair — especially if they are undergoing chemotherapy.

These patients have increasingly turned to biotin, also known as vitamin B7 or vitamin H, to boost their hair growth and thickness.

Now, an oncodermatologist at The Ohio State University Comprehensive Cancer Center is warning against biotin use, claiming that it can cause inaccurate, misleading lab test results that can upend patients’ treatment plans.

“Biotin does not actually change the levels of hormones in the body, but it interferes with the way those levels could be checked when blood work is done,” said Dr. Brittany Dulmage, associate director of dermatology at Ohio State’s College of Medicine and director of the Oncodermatology Clinic.

Here’s everything you need to know about biotin supplements — whether you have cancer or not.

What is biotin?

The water-soluble B-complex vitamin helps metabolize carbohydrates, fats and proteins into energy.

It also supports the production of keratin, a structural protein essential for the strength and protection of hair, skin and nails.

Biotin is found in many foods — the highest concentrations are seen in egg yolks, organ meats, nuts, seeds and sweet potatoes.

Because it’s so readily available, biotin deficiency is rare.

Dulmage said deficiency could manifest as problems with vision and hearing, seizures, muscle weakness or developmental delays.

“There can also be rashes that look similar to eczema and more widespread hair loss,” Dulmage told The Post.

What happens when cancer patients take biotin?

Biotin — especially in high doses — can significantly interfere with hormone and cardiac lab tests, potentially affecting the treatment of thyroid, ovarian, breast and prostate cancers. 

“For some of the hormones, such as prostate-specific antigen, PSA, or thyroid-stimulating hormone, TSH, it may falsely suppress or lower those levels, potentially masking cancer recurrence in cancer survivors,” Dulmage explained.

“For reproductive hormones, including estrogen and testosterone, it may falsely elevate levels, resulting in delayed therapy.”

Even if you don’t have cancer, biotin supplements can mess with thyroid testing, at-home urine testing for pregnancy and cardiac troponin testing, used to diagnose a heart attack.

If you don’t want to give up biotin supplements, Dulmage advises stopping them 72 hours before blood work.

Which hair growth treatments should you take if you have cancer?

Dulmage recommends taking topical or low-dose minoxidil — sold under the brand name Rogaine — instead of biotin supplements, unless the patient is pregnant or breastfeeding.

Special caps that cool the scalp to between 64 and 72 degrees Fahrenheit can also prevent or minimize hair loss by limiting the amount of chemotherapy medication reaching the hair follicle cells.

Are there other supplements to avoid if you have cancer or are in cancer remission?

“More than half the patients who come to see me with a problem related to hair loss are on a supplement that they’ve started on their own after learning about it online, by word of mouth and sometimes even at the advice of their doctor,” Dulmage said.

She cautions against:

• Saw palmetto — found in hair, skin and nail supplements — which can indirectly increase estrogen levels, potentially affecting hormone-sensitive cancers such as breast cancer.
• Vitamin B12 taken before and during chemotherapy “has been shown to be statistically associated with poorer disease-free survival and overall survival, though the mechanism of this effect is unclear,” Dulmage said.
• Similarly, iron supplementation before and during chemotherapy has been associated with a higher risk of breast cancer recurrence.

“My main advice to oncology patients with supplement use is to let your oncology team know what you are taking and what you hope to gain from a particular supplement,” Dulmage said.

“They can confirm if a particular supplement is acceptable and recommend alternative treatment approaches if necessary.”