With the introduction of SPF50+ sunscreens into Australia in late 2012, early 2013, there had been, and continues to be, a belief by some (including some fairly reputable organizations), that there is a negligible increase in protection as compared to previous generation SPF30+ sunscreens. Given SPF is the acronym for ‘Sun Protection Factor’, logic should prevail that 50+ provides considerably better protection than 30 and it is, twice as good in fact!
The articles that have been written dismissing SPF50+ will always raise a supposed minor change in protection by referring to a “1.3% increase in protection” which is an incorrect representation of a factual figure. There is a 1.3% increase, however the increase relates to the absorbance, where SPF30 sunscreen absorbs 96.67% of UVB radiation (and plenty of UVA also), whilst SPF50 sunscreen absorbs 98.00% of UVB radiation (SPF50+ actually absorbs over 98.33%). If we presume an SPF30 sunscreen was to provide 300 minutes of protection, an SPF50 sunscreen certainly does not offer a paltry additional 3.9 minutes in the sun (300 minutes multiplied by the supposed “1.3% increase in protection”).