University of Leicester researchers hope to discover the perfect amount of sun for your skin

Posted by pt91 at Sep 02, 2013 10:55 AM |
University of Leicester researchers hope to use innovative tests to reveal how much skin damage occurs at different light intensities

Issued by University of Leicester Press Office on 2 September 2013

After the summer sunshine, most of us know it is important to use sun cream to avoid sun burn.

However, it is important to also remember that sunlight is actually an important source of vitamin D – far better than food.

The problem is that we don’t have much idea of exactly how much sun our skin needs to make vitamin D before damage starts to occur.

Thankfully, University of Leicester researchers are hoping to determine exactly how much skin damage occurs for different intensities of light – as well as for different skin tones.

They aim to put their results together with parallel tests being carried out at the University of Manchester into how much vitamin D your skin produces at different strengths of light.

They hope the two sets of results will tell us the ideal amount of sun exposure for our skin.

This could be extremely beneficial, as too much sun can increase our risk of skin cancer – but it is also important to get enough sunlight so we can create the vitamin D we need to maintain healthy bones.

A team based in the University’s Department of Cancer Studies and Molecular Medicine are using an innovative urine test to show how much evidence of skin damage there is in people who have been exposed to different levels of ultraviolet (UV) light.

The test uses mass spectrometry to identify the levels of cyclobutane pyrimidine dimers in each urine sample.

Cyclobutane pyrimidine dimers are modifications of DNA, caused by UV light exposure.  As they can be harmful to the cell, they are removed, and ultimately appear in the urine where they are a strong indicator of how much damage has occurred in skin cells.

The researchers are investigating the impact of different amounts of light and different skin tones on the levels of this damage in urine.

Simultaneously, researchers at the University of Manchester are investigating how much Vitamin D and DNA damage is produced in the skin when people of different skin tones are exposed to various intensities of simulated sunlight.

Together, the team hope to draw from both sets of results to determine the optimal sunlight exposure levels for people of all skin tones.

It is still early days for the project, and definitive results are still a little way off.

But in time, the researchers hope their findings will be used by health authorities to form more detailed and personalised recommendations for the public on sun exposure.

The researchers are currently studying urine samples collected as part of the study. However, the researchers in Manchester are particularly looking for volunteers of African/Caribbean and South Asian descent living in the Greater Manchester area.

The project has been funded by Cancer Research UK, but has also attracted significant funding from a range of other sources for related aspects of the work.

Principal investigator Dr Marcus Cooke, of the University’s Department of Cancer Studies and Molecular Medicine, said: “The purpose of this project is to develop trials to look at the risk-benefit balance of UV exposure.

“The risk of sunlight exposure is the potential for DNA damage – which can cause cancer – while the benefit is that it stimulates vitamin D production.

“At the moment, nobody really knows where the balance is. We are hoping that this work will provide evidence from which advice can be given and that, through our data, this advice can be tailored to a range of different skin types.

“We hope the results can help to shape policy advice for health authorities and charities on the right levels of sun exposure for individuals.”



Please contact:

Dr Marcus S. Cooke, Senior Lecturer in the Oxidative Stress Group, University of Leicester's Department of Cancer Studies and Molecular Medicine and Department of Genetics, at:

For information on the human volunteer studies: Mrs Joanne Osman, Photobiology Unit, Dermatology Research Centre, Salford Royal Hospital, Greater Manchester, or at:

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