A number of clinical trials have been conducted in order to substantiate Bio‑Oil's various claims.

In 2005 three single blind, single product, randomized and controlled trials were conducted at the Photobiology Laboratory of MEDUNSA (Medical University of South Africa). Results confirmed that Bio‑Oil effectively improves the appearance of scars, stretch marks and uneven skin tone.

In 2010 further trials were conducted by proDERM, a leading institute for applied dermatological research based in Hamburg, Germany. Results showed that Bio‑Oil is efficacious in improving the aesthetic outcome of scars and stretch marks in double-blind, placebo controlled clinical studies.

In 2011 Stephens & Associates conducted a 12-week trial, which showed that Bio‑Oil is efficacious in improving the overall appearance of photodamaged (aging) skin on the face, neck and body; the study also provided further substantiation for Bio‑Oil's uneven skin tone claim. Also in 2011, MEDUNSA conducted two clinical studies to substantiate Bio‑Oil's dehydrated skin claim.

Finally, in 2012 Peking University First Hospital in Beijing conducted an exploratory study to assess the efficacy of Bio‑Oil in improving the appearance of facial acne scars.