The brighter side of sunshine
Some scientists are saying that the health benefits of sunbathing might outweigh skin cancer risks
Sunbathing reduces blood pressure, cuts the risk of heart attack and is more likely to prolong life than shorten it, says a new study. Sun worshippers worried by gloomy warnings that they risk getting skin cancer can now start looking at the bright side.
Dermatologist Dr Richard Weller, whose team conducted the study, said, "We suspect that the benefits to heart health of sunlight will outweigh the risk of skin cancer." The discovery is that when skin is exposed to sunlight, a compound called nitric oxide is released in blood vessels that helps lower blood pressure. So far, it has been believed that the only health benefit the sun offered was Vitamin D, which assists bone growth, boosts the immune system and also controls blood pressure.
Dr Weller said, "Our work also explains why dietary Vitamin D supplements alone will not be able to compensate for lack of sunlight."
The experiment
The Edinburgh University team sat 24 volunteers beneath tanning lamps for two sessions of 20 minutes each and measured their blood pressure. In one session they were exposed to both UV rays and the lamp heat. In the other, the UV rays were blocked, as if wearing sunscreen. So, only the heat of the lamps affected the skin.
The findings
The results showed that blood pressure dropped significantly for one hour following exposure to UV rays, but not after the heat-only sessions. This indicated that the sun's UV rays promote the production of the blood pressure-lowering nitric oxide. There are different bands of UV rays in sunlight. The lowest band, UVA, induces the production of vitamin D. UVB is the band that causes sunburn and skin cancer.
The team's risk assessment comes from the estimate that heart disease and stroke linked to high blood pressure kills 80 times more people than skin cancer in the UK.
Dr Weller said his team still needs to look at the relative risks of heart disease and skin cancer in people who have received different amounts of sun exposure.
He said, "If this confirms sunlight reduces the death rate from all causes, we will need to reconsider our advice on sun exposure." The findings will be presented this week at a gathering of skin experts.
Sunbathing reduces blood pressure, cuts the risk of heart attack and is more likely to prolong life than shorten it, says a new study. Sun worshippers worried by gloomy warnings that they risk getting skin cancer can now start looking at the bright side.
Dermatologist Dr Richard Weller, whose team conducted the study, said, "We suspect that the benefits to heart health of sunlight will outweigh the risk of skin cancer." The discovery is that when skin is exposed to sunlight, a compound called nitric oxide is released in blood vessels that helps lower blood pressure. So far, it has been believed that the only health benefit the sun offered was Vitamin D, which assists bone growth, boosts the immune system and also controls blood pressure.
Dr Weller said, "Our work also explains why dietary Vitamin D supplements alone will not be able to compensate for lack of sunlight."
The experiment
The Edinburgh University team sat 24 volunteers beneath tanning lamps for two sessions of 20 minutes each and measured their blood pressure. In one session they were exposed to both UV rays and the lamp heat. In the other, the UV rays were blocked, as if wearing sunscreen. So, only the heat of the lamps affected the skin.
The findings
The results showed that blood pressure dropped significantly for one hour following exposure to UV rays, but not after the heat-only sessions. This indicated that the sun's UV rays promote the production of the blood pressure-lowering nitric oxide. There are different bands of UV rays in sunlight. The lowest band, UVA, induces the production of vitamin D. UVB is the band that causes sunburn and skin cancer.
The team's risk assessment comes from the estimate that heart disease and stroke linked to high blood pressure kills 80 times more people than skin cancer in the UK.
Dr Weller said his team still needs to look at the relative risks of heart disease and skin cancer in people who have received different amounts of sun exposure.
He said, "If this confirms sunlight reduces the death rate from all causes, we will need to reconsider our advice on sun exposure." The findings will be presented this week at a gathering of skin experts.
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