I am a retired epidemiologist with expertise in skin cancer prevention, so I read your most recent post with great interest.
First, let me congratulate you on going down the sunscreen rabbit hole! It's a complex topic and difficult to study epidemiologically as it relates to risk of melanoma because melanoma is so rare. Below are a few po…
I am a retired epidemiologist with expertise in skin cancer prevention, so I read your most recent post with great interest.
First, let me congratulate you on going down the sunscreen rabbit hole! It's a complex topic and difficult to study epidemiologically as it relates to risk of melanoma because melanoma is so rare. Below are a few points I would like to add to your commentary.
1. Regarding proper use of sunscreen, we found in a case-control study we conducted (Cancer Epidemiol Biomarkers Prev. 2011 Dec;20(12):2583-93), that individuals do not use sunscreen properly. They do not apply sufficient amounts to obtain the benefit of the SPF, whether it's 30 or 50 and they do not reapply it as necessary. In our study, we found that use of sunscreen was either not associated or only weakly associated with melanoma risk, most likely, because improper use limits our ability to identify an association, if one exists. Furthermore, studies have shown that using even 50% of the recommended amount reduces the SPF protection, regardless of the factor, to very low levels of minimal benefit (Schneider, J. Arch Dermatol 2002;138:838-b-839-b). Inadequate application of sunscreen that leads to very low SPF is an important point to emphasize.
2. In our case-control study, the most consistently robust finding was for a decreased risk of melanoma if other sun protection methods were used, namely avoidance or covering up. Our results for methods other than sunscreen are consistent with the World Health Organization recommendations that place priority on these sun protection methods, and advise using sunscreen ONLY in conjunction with one of these other methods. The Australian Slip, Slap, Slop graphic you presented does not make this point clearly and I think our public health messaging for sun protection needs improvement, especially as in this country, studies have shown that most Americans associate sunscreen use with skin cancer prevention, even though the evidence is weak.
3. As for additional nuances, there is the concern that people use sunscreen to prolong their time in the sun. And if, as is likely, they are not using sunscreen properly, and are only using sunscreen and not one of the other methods, then they are very likely increasing their risk for skin cancer. Again, our public health messaging on sun protection is inadequate.
4. Lastly, you did not mention spray-on sunscreen. This application method should be discouraged as there is no way to know how much sunscreen is reaching the skin. I know it is a popular method with parents of young children due to its ease of application. However, parents need to know that spray-on sunscreen is not protecting their children,
Congratulations on your recent TIME recognition and the hard work of translating epidemiology for the public
I am a retired epidemiologist with expertise in skin cancer prevention, so I read your most recent post with great interest.
First, let me congratulate you on going down the sunscreen rabbit hole! It's a complex topic and difficult to study epidemiologically as it relates to risk of melanoma because melanoma is so rare. Below are a few points I would like to add to your commentary.
1. Regarding proper use of sunscreen, we found in a case-control study we conducted (Cancer Epidemiol Biomarkers Prev. 2011 Dec;20(12):2583-93), that individuals do not use sunscreen properly. They do not apply sufficient amounts to obtain the benefit of the SPF, whether it's 30 or 50 and they do not reapply it as necessary. In our study, we found that use of sunscreen was either not associated or only weakly associated with melanoma risk, most likely, because improper use limits our ability to identify an association, if one exists. Furthermore, studies have shown that using even 50% of the recommended amount reduces the SPF protection, regardless of the factor, to very low levels of minimal benefit (Schneider, J. Arch Dermatol 2002;138:838-b-839-b). Inadequate application of sunscreen that leads to very low SPF is an important point to emphasize.
2. In our case-control study, the most consistently robust finding was for a decreased risk of melanoma if other sun protection methods were used, namely avoidance or covering up. Our results for methods other than sunscreen are consistent with the World Health Organization recommendations that place priority on these sun protection methods, and advise using sunscreen ONLY in conjunction with one of these other methods. The Australian Slip, Slap, Slop graphic you presented does not make this point clearly and I think our public health messaging for sun protection needs improvement, especially as in this country, studies have shown that most Americans associate sunscreen use with skin cancer prevention, even though the evidence is weak.
3. As for additional nuances, there is the concern that people use sunscreen to prolong their time in the sun. And if, as is likely, they are not using sunscreen properly, and are only using sunscreen and not one of the other methods, then they are very likely increasing their risk for skin cancer. Again, our public health messaging on sun protection is inadequate.
4. Lastly, you did not mention spray-on sunscreen. This application method should be discouraged as there is no way to know how much sunscreen is reaching the skin. I know it is a popular method with parents of young children due to its ease of application. However, parents need to know that spray-on sunscreen is not protecting their children,
Congratulations on your recent TIME recognition and the hard work of translating epidemiology for the public
DeAnn Lazovich, Ph.D.
Associate Professor Emerita
Division of Epidemiology and Community Health
School of Public Health
University of Minnesota