Hundred is two times fifty. But when it comes to sunscreens meant to protect your skin from the harsh ultraviolet rays of the sun, this simple arithmetic does not apply. A sunscreen with an SPF (Sun Protection Factor) of 100 is not twice as effective as SPF 50.
If you look at sunscreens in the market, you will notice that their SPF factor usually varies from 15 to 100. While SPF 15 blocks 93 per cent of ultraviolet B rays, SPF 30 blocks 97 per cent. After that, an increase in SPF does not offer any significant advantage.
While SPF 50 offers 98 per cent protection from UVB rays, SPF 100 provides you with 99 per cent protection (some experts even say that it is only 98 per cent).
In fact, the Food and Drug Administration (FDA) in the United States says there is no sufficient data to show that products with values higher than 50 provide greater protection than products with SPF values of 50.
And no product completely blocks all wavelengths of ultraviolet light or gives complete protection.
Since consumers are not aware of this, they end up spending money on sunscreen products that do not give them any advantage commensurate with the increase in costs.
It’s for this reason that many countries around the world have labeling regulations that limit the maximum SPF value indicated on sunscreen. While the (FDA) has proposed a rule that limits the maximum SPF value on sunscreen labels to 50, Australian regulation mandates a maximum of 30. Those with a value higher than SPF 30 can only declare it as 30+.
A good sunscreen should be capable of shielding your skin from the harmful effects of both UVB and UVA rays. While internationally, SPF values denote the level of protection against UVB rays, there is no such common international indicator for UVA. So different countries have adopted different methods of expressing it.
In the United States, for example, where the incidence of skin cancer caused by ultraviolent rays is high, the term ‘Broad spectrum’ represents protection against both UVA and UVB. And only those sunscreens that offer UVA protection proportional to UVB and pass the FDA’s tests formulated for the purpose are allowed to claim that on the label.
In India, you find some sunscreen labels mentioning only the SPF factor, while some indicate in addition that it screens both UVB and UVA. Yet others indicate the SPF and the PA values. You also find some of them using the term ‘Broad spectrum’.
It’s time we enforced a uniform labeling norm, which is also simple and unambiguous, for all sunscreens sold in the country so that consumers are in a better position to compare products and make an informed choice. Regulators should ensure that when a product claims to be made only from natural ingredients, it really is so.
Several countries, I must mention here, prohibit manufacturers from using terms like ‘sunblock’ (no sunscreen can completely block the UV rays) or ‘water proof’ (they should use the term water resistant instead) or ‘instant protection’ on the ground that they are misleading.
Sandhya Sharma: There are so many sunscreens in the market these days, how does one choose the right one? And what is the SPF number that they indicate?
Answer: Hopefully, the information that I have given above will be of help. Read the label and follow instructions to get the best out of a sunscreen.