This article is sourced from the “Shanghai Network Rumor Refutation”;
This year, sunbathing is especially popular. When the sun comes out, you can see the “sunbathing tribe” everywhere in the park, on the grass, and on rooftops. Many people bare their upper bodies, wearing only underwear or covering their faces with a cloth while lying on the ground to sunbathe. Some say, “Sunbathing is a free ‘moxibustion'” “Sunbathing can help lose weight, remove dampness, and detoxify,” while others believe, “Getting tanned, turning red, or breaking out in a rash means it’s effective.” Online, there are businesses selling “sunbathing clothes,” that expose the back.
So, does sunbathing really have that many effects?
The “sunbathing tribe” can be seen everywhere in the park, on the grass, and rooftops.
Don’t expect “Sunbathing to lose weight”
Recently, “Lose 4 pounds in 10 days of sunbathing” has become a hot topic online. In reality, sunbathing for long periods can lead to dehydration. Short-term weight changes may be due to loss of water, not fat burning, so the claim of “sunbathing for weight loss” is not reliable.
Although studies have found that blue light in sunlight can activate ion channels in fat cells, thereby activating signal pathways that regulate lipid metabolism in fat cells, initiating lipid breakdown metabolism, this only indicates that “sunlight helps maintain normal fat metabolism in the body” and cannot be used as a basis for weight loss.
Beware of heatstroke when sunbathing during the “Dog Days of Summer”
Zhou Yang, director of the Department of Preventive Treatment at the Yueyang Integrated Chinese and Western Medicine Hospital affiliated with the Shanghai University of Traditional Chinese Medicine, believes that in traditional Chinese medicine, the back of the human body has two meridians – the Du meridian and the Bladder meridian of the Foot-Taiyang. The Du meridian governs the body’s yang qi, while the Bladder meridian of the Foot-Taiyang is prone to external invasion by pathogenic cold and dampness, leading to illness. Sunbathing can help to invigorate yang qi, disperse cold, and remove dampness. However, this does not mean that everyone should sunbathe. It is especially not recommended to sunbathe at noon when the sun is strongest during the Dog Days of Summer. With Shanghai recently issuing consecutive red alerts for high temperatures, many people sunbathing in parks may easily suffer from heatstroke or even heat exhaustion, which is strongly discouraged. Furthermore, prolonged exposure to high temperatures can cause dehydration. Under the sun for a long time, the body sweats a lot, and if not replenished in a timely manner, it can lead to dehydration and may even endanger life.
“Getting tanned, turning red, or breaking out in a rash” indicates sunburn
The trend of “Sunbathing for health” has become popular, with some netizens openly sharing issues like red, swollen, itchy skin after sunbathing, with some believing that achieving such results signifies effectiveness. However, in reality, the claim that “Getting tanned, turning red, or breaking out in a rash means it’s effective” is purely a rumor.
Some netizens experience issues like getting tanned, turning red, itching, or breaking out in a rash after sunbathing.
Yuan Chao, chief physician of the Department of Dermatology and Cosmetology Research at the Shanghai Skin Hospital, pointed out that photosensitive individuals are not suitable for sun exposure. Strictly speaking, a skin phototest should be done before sun exposure. If the result is positive, sun exposure should be avoided, and only those with negative results can sunbathe. Doctors will assess if patients are suitable for sun exposure based on the minimum erythema dose (MED) of their skin. For photosensitive individuals who forcibly sunbathe, issues such as sunburn, polymorphic light eruption, and solar urticaria may occur.
The UV rays are strong in summer, and even non-photosensitive individuals should not persistently sunbathe for health reasons. UVA in sunlight can cause skin photoaging and skin cancer, while UVB can cause sunburn and pigmentation issues. Therefore, even healthy individuals should sunbathe moderately.
What is the correct way to sunbathe?
Chao believes that the following groups should avoid excessive sun exposure: patients with skin diseases or cardiovascular diseases; individuals taking photosensitive drugs.
How healthy individuals should sunbathe
The best times are in the morning from 8:00-9:00 and in the afternoon after 15:00, avoiding the strongest sunlight periods. Sunbathe for a maximum of 15 minutes per day, gradually increasing exposure, for example, 5 minutes on the first day, 6 minutes on the second day, to allow the body to adapt gradually.
Pre-sunbathing preparation:
1. Drinking water.
The daily water intake for adults should be 1500-1700 ml. The WHO recommends that the water intake in summer should be 1.5 times the usual amount, i.e., 2250-2550 ml. After sweating heavily, it is best to replenish water with electrolyte solutions and avoid alcohol, coffee, and sugary drinks.
2. Sunscreen.
Sun protection measures should be taken, especially for the head, face, and eyes, which should not be exposed directly to sunlight. Sunbathing is to absorb heat energy from the sun, so it is recommended to wear light clothing or apply sunscreen before sun exposure to avoid skin damage caused by UV rays.
[Attention]
As long as there is slight sweating during sunbathing, it is sufficient; excessive sun exposure and overheating are not advisable. Be especially vigilant for symptoms of dehydration, heatstroke, etc. If you sweat profusely, have an abnormal increase in body temperature, feel weak, dizzy, thirsty, these are likely signs of heatstroke, and prompt medical attention is necessary.
Avoid eating photosensitive foods before sunbathing, such as amaranth, celery, rapeseed, spinach, bok choy, pomelo, lemon, mango, fig, lettuce, buckwheat, snails, as these foods can increase sensitivity to UV rays, making it easier to develop solar dermatitis.
In fact, you can sunbathe all year round as long as the sun is out, not just limited to summer. Sunbathing in winter can also boost mood. Everyone should take a scientific approach to sunbathing for health and not just follow trends.
