Received: 4 January 2019
Revised: 30 August 2019
Accepted: 10 September 2019
First Online: 23 September 2019
Compliance with ethical standards
: BetterYou co-funded this PhD and provided the supplements and placebos. This sponsor was not involved in the study design, delivery or interpretation of the data, which was undertaken entirely by The University of Sheffield. The authors declare that they have no conflict of interest.