Sunbathing after 10 AM is dangerous: a fact or myth?

Sunbathing on a cruise ship in 2009 (giggel)

Morning sunshine does produce UV rays that can be converted by our body into vitamin D. Our body needs this vitamin to metabolize calcium, maintain our immune system, and transmit impulse from the nerves to the muscle.

So, what time should we sunbathe, and what are the dangers of UV rays on our bodies?

According to the World Health Organization (WHO), overexposure to sunlight can harm the skin, eyes, and the immune system. Experts believe that four out of five cases of skin cancer can be prevented by avoiding excessive UV light exposure.

Wearing unrevealing clothing, headgear such as hats, sunglasses, and putting on sunscreen can protect us from the sun's ultraviolet radiation. According to the WHO, a broad-spectrum sunscreen of SPF 15+ is enough to protect our hands and face for about two hours. However, reapplying sunscreen and continuing sunbathing is not good for the skin.

The WHO also explained that UV rays from 10 a.m. to 4 p.m. were more dangerous. The agency also suggested reducing the intensity of exposure without protection at these hours.

Demonstration of the effect of sunscreen: The man's face has sunscreen on his right only. The left image is a regular photograph of the face. The right image is taken by reflected UV light. The side of the face with sunscreen is darker because it absorbs the UV light. (Spigget)

In addition, it is also important to know the UV Index. The UV Index is the level of UV radiation whose values differ throughout the day. This UV Index value depends on the geographical location of a country or region.

UV Index in the range of 1 to 2 is safe. In this range, people can be outside without certain protection. Then, in the range of 3 to 7, people need protection such as headgear or sunscreen. This range is usually around midday.

Then, in the range of 8 to 11, people need extra protection. In this range, it is not recommended to leave the house without protection for the skin and eyes.

Mild Reports tried to observe the UV Index forecast in San Jose, California, on April 13, 2020, through the monitoring website sunburnmap.com. By clicking the skin type 2 related to the characteristics of its residents - blond-haired, hazel-eyed, and white-skinned - the website recommended the estimated time for sunbathing at certain hours.

At 8 a.m., for example, when the UV Index is estimated at 1, people can sunbathe to their heart's content. Then, at 10 a.m., when the UV Index is estimated at 3, people can sunbathe up to 56 minutes. Then, at noon, when the UV Index is at 6, sunbathing should be done for a maximum of 28 minutes.

At 1 p.m. in San Jose, the UV Index has reached 7. In this time frame, people should not get too much UV exposure. If you want to bask in this range, 24 minutes is the maximum recommended time. The UV Index in San Jose is expected to decline to 5 at 3 p.m.

At 1 to 2 p.m., the exposure to sunlight in high intensity for a long period can be harmful to the skin because the UV Index is estimated to be above 6. If you have to move at that time, you should use protection such as headgear, sunglasses, and sunscreen.

Important note: ozone can affect UV Index values.

It can be concluded that, in San Jose, the best time for sunbathing is between 8 to 11 a.m. During this time, the UV Index is not expected to be too dangerous for the skin and eyes.

UV Index can be different in each country depending on climate and its location on the equator.