WHACK-A-MOLE: Whacking non-evidence-based claims on the head: Effect of Irvingia Gabonesis on body weight, glucose and blood cholesterol

  • Huntley Antippa, Sophia (Other)
  • Evens, Paige (Other)
  • Ho, Jeremy (Other)
  • Del Mar, Chris (Professor)
  • Harvey, Kenneth (Associate Investigator)
  • Diug, Basia (Associate Investigator)
  • Stehlik, Paulina (Project Lead)

Project: Research

Project Details


Introduction/ Background
Advertising of therapeutic goods, as opposed to other goods and services, is held to a higher standard in order to protect consumers when relying on such products for their health. Ensuring truthful and clear information is vital. The Therapeutic Goods Act 1989 (the Act) and the Therapeutic Goods Advertising Code (No. 2) 2018 states that “advertising [must be] … conducted in a manner that: (b) is ethical and does not mislead or deceive the consumer or create unrealistic expectations about product performance.”

We reviewed African Mango Seed Extract, which appears to have breached these regulations. This report aims to evaluate the quality of available evidence addressing the products claims; “controls”4 body weight, blood glucose and blood cholesterol.

Three systematic reviews were performed. We searched Cochrane Library, PubMed, ProQuest, Embase, ClinicalTrials.gov, Google Scholar and manufacture’s websites. We included randomised trials (and in some circumstances other human study designs) of African Mango Seed Extract with any control reporting on the following outcomes: weight (weight loss and BMI), blood glucose (fasting and post-prandial BGL), and lipid (HDL, LDL, TG). Risk of bias was assess using the Cochrane Risk of Bias tool.

We found 86 studies and included five studies reporting on weight outcomes, six studies reporting on blood glucose outcomes, and four studies reporting on lipid outcomes. Heterogeneity of the studies and small study sample sizes prevented meta-analysis across all three reviews. While some studies reported positive results, overall the studies had a high risk of bias and were reported poorly.

There is insufficient evidence to suggest that IG effectively “controls” and “lowers” blood cholesterol and lipid levels. These claims should be removed from products containing IG and associated marketing materials.

1. Therapeutic Goods Act 1989, 1990 (Cth). Compilation date: 1 January 2019. Registered: 22 January 2019. https://www.legislation.gov.au/Details/C2019C00066/Download. Accessed 25 January, 2019.
2. Advertising to the public: Complying with the Therapeutic Goods Advertising Code (No. 2) 2018. Therapeutic Goods Administration Web site. https://www.tga.gov.au/publication/advertising-public. Updated January 2019. Accessed 25 January, 2019.
3. Therapeutic Goods Advertising Code (No.2) 2018 (Cth). Dated: 31 October 2018. https://www.legislation.gov.au/Details/F2018L01524. Accessed 25 January, 2019.
4. African Mango Extract Australia: How it works, Buy now. African Mango Extract Australia Web site. https://www.africanmangoextractaustralia.com/. Accessed 29 July, 2019.

Plain Language description

Why “Whack-a-mole”: Because, given deficiencies in the current regulatory system, no sooner does one miscreant get “whacked” than another (or the same one) pops up!

Project Aims

To evaluate the quality evidence (or lack there-of) supporting therapeutic claims made by a therapeutic good and/or service, and where product sponsors have breached advertising regulations, to make a submission to the relevant regulatory body.
Short titleWhack-a-mole
Effective start/end date1/08/189/08/19