Sunscreen slows wrinkles and allows for vitamin D absorption, say new studies

No more lazy excuses, folks. Time to lather on that sunscreen.

Two new studies show the benefits of sunscreen -- one suggests it reduces signs of aging and another shows it allows for some vitamin D absorption, despite fears it may block it entirely.

In the first study, a group of Australian researchers say that sunscreen decreases signs of aging by reducing the amount of wrinkles, among other things. This is the first major study of its kind, as previous research on how sunscreen affects aging has only been conducted on mice.

The research, published Monday in the journal Annals of Internal Medicine, was financed by the Australian government and Ross Cosmetics, an Australian company that makes the sunscreen used in the study.

Scientists from the Queensland Institute of Medical Research tracked 903 Australians age 55 and younger for a total of 4½ years. Participants were put into two groups, one that used sunscreen daily -- rubbing it on face, neck, arms and hands -- and the other who used sunscreen when they felt they needed it.

At the end of the 4½ years, members of the first group were 24 per cent less likely to show signs of increased aging, including wrinkles, dark spots and skin coarseness.

Also see: Sunscreen excuses you need to ditch right now

"We weren't surprised by the findings, but we now have the science to back it up," lead author Adele Green, a senior scientist at the Queensland Institute of Medical Research, tells ABC.

The researchers speculated that the group told to use SPF 15 every day throughout all seasons would probably slack, and indeed they did, proving to only use the sunscreen about 3-4 times a week.

Yet despite this reduced amount of sunscreen they still benefited from less signs of aging. It didn't matter how much aging had already occurred, but whether a liberal dose of sunscreen was used.

"I'm fond of telling people that if they start using sunscreen on a regular basis and don't do anything else, over a period of time they'll see an improvement in the appearance of their skin," Dr. Richard Glogau, a clinical professor of dermatology at the University of California who was not involved in the study, tells the Associated Press. "It's never too late."

In the second study, U.K. researchers suggest that people can get absorb a significant amount of vitamin D even when using sunscreen.

The research, not yet published, was partly funded by the pharmacy retail store Boots.

Also see: 'Bad' sunscreens you should avoid

Antony Young, a professor of experimental photobiology at King's College London, analyzed the vitamin D levels of 79 men and women on a week long vacation in Tenerife in the Canary Islands.

Participants were split into two groups, those that were told to use a specified amount of SPF 15 from after breakfast until sundown and taught how to apply it, and those that were instructed to use sunscreen whenever they felt they needed it. Both groups had their vitamin D levels checked at the start of their vacation and at the end.

The results showed that those who were instructed on how and when to use sunscreen had an increase in vitamin D levels of 16 nanomoles (nml) per litre of blood. While they showed significantly lower levels of vitamin D than those who were allowed to use sunscreen at their discretion, averaging 28 nanomoles (nml) per litre of blood, it was still a substantial amount.

"That is still a significant rise in vitamin D levels," Young tells the Daily Mail in relation to the first group. He believes his results show that some UV will get through sunscreen.

It's worth noting, as well, that the group who used sunscreen more frequently were substantially less burned by the end of their vacation.

With both these studies in mind, will you change your sunscreen habits in anyway? Do they provide a compelling enough reason to use it more often?