As research demonstrating efficacy of Biotin supplementation is limited, if one is healthy, taking biotin supplementation probably does very little to improve ones genetic hair loss. This is contrary to all what is seen advertised in the media/social media.
Biotin (also called vitamin B-7) is a co-factor in many enzymes that play a part in numerous metabolic process including keratinisation of hair and nails. It is found in many foods like sweet potatoes, avocados, nuts, yeast, salmon. It is also made in the gut.
At present, there are no studies that show deficiency in healthy individuals with a balanced diet. Deficiency is rare but can happen due to genetic causes, during pregnancy, alcoholism, impaired intestinal absorption, taking medication like valproic acid, isotretinoin and long term antibiotics that affect the gut flora. Interestingly, consuming raw eggs causes biotin deficiency.
A 2017 systematic review was carried out on all random clinical trials carried out and published about biotin and hair growth. In 18 reports, biotin supplementation helped in cases where patients had seriously established deficiency of biotin. There has been no randomised controlled trials to prove that biotin supplementation helps hair loss in healthy patients.
Furthermore, taking Biotin supplements can affect the accuracy of many blood tests carried out resulting in false readings. It is important, to stop taking Biotin at least 3 days before a blood test.