A Consumer NZ test of kiwi sunscreen brands is misleading and dangerous, warns a Vitamin D researcher and author, because it ignores an elephant in the room - there's growing evidence sunscreens don't actually protect kiwis from melanoma at all.
"This Consumer test of whether sunscreens match their SPF ratings is dangerous," says Ian Wishart, "because it perpetuates the myth that slapping on a high SPF sunscreen will stop you developing melanoma. The latest scientific reports suggest sunscreens are as effective as lolly water."
In recent years, reports a 2015 Italian medical study, “many researchers have epidemiologically studied whether sunscreen use influences the malignant melanoma (MM) incidence upon sun exposure. Surprisingly, most of the researchers observed that sunscreen users have a higher incidence of MM than non-users.”1
That study explores the possibility that chemicals in sunscreen may actually cause cancer, not reduce it.
"I would have thought Consumer would be looking much deeper at the multi-billion dollar marketing scam that sunscreens appear to be," says Wishart.
A 2017 US Government scientific review of sunscreens and skin cancer found:2
• "The evidence that interventions designed to reduce exposure to UV radiation by the use of sunscreen, protective clothing, or limitation of sun exposure time decrease the incidence of nonmelanoma skin cancer is inadequate."
• "It is possible that individuals who use sunscreen may experience excess sun exposure because they avoid sunburn but do not avoid harmful UV radiation."
• "There is inadequate evidence to determine whether the avoidance of sunburns or the use of sunscreen alters the incidence of cutaneous melanoma."
• " A meta-analysis of 18 studies that explored the association between melanoma risk and previous sunscreen use illustrates widely differing study qualities and suggests little or no association.36 A systematic review of the association between sunscreen use and the development of melanocytic nevi in children reported similar issues with study quality and heterogeneity, hindering conclusive assessments; however, of 15 studies meeting inclusion criteria, 12 found either an increased incidence or no association.37 Thus, the current evidence indicates that sunscreen application as practiced in the general population shows no clear association with reduced risk of melanocytic nevi or melanoma."
In summary, says Ian Wishart, "Consumer's study blathering on about SPF factors is utterly irrelevant. The much bigger fundamental question Consumer should have asked is this: After 50 years of sunscreen use, what hard evidence is there that the billions of dollars spent on sunscreen by consumers has saved even one life? The studies indicate sunscreens are killing more people than they are saving.
"As the US National Cancer Institutes 2017 review found, there is scientific evidence to suggest that sunscreens actually cause melanoma by preventing sunburn but not reducing dangerous UV exposure, giving consumers a false sense of protection. If sunscreens are causing melanoma, New Zealanders deserve to know."
Wishart is the author of two bestselling health books, Vitamin D  and Show Me The Money Honey , and has debated the efficacy of sunscreens directly with the Cancer Society of New Zealand. For both books he conducted an extensive review of scientific papers on sunscreen efficacy.