[Spring UV Awareness Survey] 61.3% Do Not Know "Full-Scale UV Care is Necessary from April", 72.0% of Those with Pigmentation Regret "Should Have Taken Measures Earlier" - IC Clinic Survey

[Conclusion] Points of this Survey **To conclude, the amount of ultraviolet (UV) rays in April reaches about 80% of midsummer, so it is necessary to start full-scale UV care from April. To prevent pigmentation after sunburn, in addition to using sunscreen, moisturizing care and vitamin C intake within 72 hours immediately after UV exposure are effective. The minimum necessary UV care in spring is to apply sunscreen of SPF30 or higher and PA+++ or higher every day, and reapply every 2 to 3 hours.**

- It was found that 61.3% of people do not know that full-scale UV care is necessary from April. - 72.0% of people who have experienced pigmentation due to sunburn regret that they "should have taken measures earlier". - Only 23.7% of people use sunscreen every day as a UV measure in spring.

Glossary ### ■ What are Ultraviolet (UV) Rays? Ultraviolet rays are electromagnetic waves with a wavelength of 280 to 400 nm contained in sunlight. They are classified into UVA (long-wavelength ultraviolet rays) and UVB (medium-wavelength ultraviolet rays). UVA reaches the dermis and causes wrinkles and sagging, while UVB acts on the epidermis and causes spots and sunburn. The amount of UV rays increases rapidly from April and approaches the annual maximum in May.

### ■ What is Pigmentation? Pigmentation is a condition in which melanin pigment accumulates excessively in the skin, leaving brown or black spots and blemishes. When exposed to stimuli such as UV rays or inflammation, melanocytes (pigment cells) excessively produce melanin, and melanin that cannot be completely discharged by turnover is deposited in the epidermis and dermis.

### ■ What are SPF and PA? SPF stands for Sun Protection Factor, a numerical value indicating the effect of preventing UVB. The higher the number, the higher the protection effect against UVB. PA stands for Protection Grade of UVA, an index indicating the effect of preventing UVA in four stages from + to ++++. SPF30 and PA+++ or higher are recommended for daily use, and SPF50 and PA++++ are recommended for leisure time.

Comparison of UV Amount by Season and Recommended Measures | Comparison Item | Spring (April-May) | Summer (June-August) | Autumn/Winter (September-March) | | --- | --- | --- | --- | | UV amount (Summer=100) | 70-80% | 100% | 30-50% | | UVA intensity | Almost the same as summer | Maximum | 50-60% of summer | | Recommended SPF | 30-50 | 50+ | 15-30 | | Recommended PA | +++ to ++++ | ++++ | ++ to +++ | | Reapplication frequency | Every 2-3 hours | Every 2 hours | Every 3-4 hours | | Ease of dropping guard | Very high | Low | Medium | *This is a general guide, and there are individual differences. Values are based on Japan Meteorological Agency UV data and Japanese Dermatological Association information.

Medical Corporation Tetsuyukai IC Clinic (Locations: Shinjuku-ku, Shibuya-ku, Taito-ku, Toshima-ku, Chiyoda-ku, Tokyo, and Saitama City, Saitama Prefecture), which specializes in skin tumors and dermatological surgery treatments, conducted a "Spring UV Awareness Survey" targeting 300 men and women in their 20s to 60s nationwide. This survey revealed the degree of awareness of the importance of UV measures from April, experience of pigmentation due to sunburn, and actual status of UV care in spring.

Background of the Survey In April, opportunities to go out increase with the start of the new fiscal year, while the amount of UV rays also increases rapidly. According to the Japan Meteorological Agency's data, the amount of UV rays in April reaches about 80% of midsummer, but many people tend to think that "UV measures start from summer." At our clinic, consultations regarding pigmentation and spots caused by UV rays tend to increase from spring. Therefore, we conducted this survey to investigate the actual state of awareness regarding UV rays in spring and to enlighten people about the importance of early measures.

Survey Overview Target: Men and women in their 20s to 60s nationwide who lead a daily life involving going out Period: March 16 to March 25, 2026 Method: Internet survey Number of respondents: 300

Survey Results ### [Result] Over 60% did not know "full-scale UV care is necessary from April" *Question: Did you know that the amount of UV rays in April reaches about 80% of midsummer, requiring full-scale UV care?* 61.3% of respondents answered they "did not know" that full-scale UV care is necessary from April. It became clear that because the temperature is still cool in spring, it is difficult to be conscious of UV rays, and many people tend to neglect measures.

### [Result] About 70% have experienced pigmentation from sunburn *Question: Have you ever experienced pigmentation (spots/dullness) due to sunburn?* A total of 70.0% of respondents answered that they "have" experienced pigmentation due to sunburn. Among them, 48.3% answered that they are still concerned about pigmentation, suggesting that once formed, pigmentation remains for a long time.

### [Result] 72.0% of those with pigmentation regret "I should have taken measures earlier" *Question: (To those who have experienced pigmentation) Do you think you should have started UV measures earlier?* Among those who have experienced pigmentation, 72.0% combining "strongly agree" and "somewhat agree" were found to regret not taking early UV measures. This indicates that prevention is important for pigmentation, and improving it after it has formed takes time and money.

### [Result] Only 23.7% use sunscreen daily in spring *Question: To what extent do you use sunscreen as a UV measure in spring (March-May)?* Only 23.7% of people "use it every day" in spring. On the other hand, those who "hardly use it" and "do not use it at all" totaled 19.6%, revealing the reality that about 1 in 5 people do not take UV measures in spring.

### [Result] Only 17.0% "well understand" the mechanism of spot formation *Question: How well do you understand the mechanism of spot formation caused by UV rays?* Only 17.0% of respondents "well understand" the mechanism of spot formation, while "do not understand much" and "do not understand at all" totaled 44.7%. A lack of understanding of the mechanism is considered a contributing factor to not taking appropriate preventive actions.

Survey Summary This survey revealed that 61.3% of people do not know that full-scale UV care is necessary from April, and the reality is that spring UV measures are not sufficiently widespread. Also, 70.0% of people have experienced pigmentation due to sunburn, and 72.0% of them regret "I should have taken measures earlier". Only 23.7% use sunscreen daily in spring, and only 17.0% fully understand the mechanism of spot formation. From these results, it was suggested that further enlightenment on the reality of spring UV levels and the importance of early measures is necessary.

Doctor's Comment | IC Clinic, Dr. Kota Takakuwa **Speaking from over 15 years of clinical experience as a dermatologist, UV measures need to start full-scale "from April," not "from summer." According to Japan Meteorological Agency data, the amount of UV rays in April reaches about 80% of midsummer, and letting your guard down during this period will cause spots and pigmentation in the future.**

I will explain the mechanism of spot formation caused by UV rays. When exposed to UV rays, melanocytes (pigment cells) in the basal layer of the epidermis are stimulated and produce melanin pigment. Normally, melanin is discharged through skin turnover (about a 28-day cycle), but repeated exposure to UV rays keeps melanocytes activated, and excess melanin accumulates to become spots.

What requires special attention is UVA (long-wavelength ultraviolet rays) in April and May. Over 80% of UVA reaches the ground even on cloudy days, and it passes through glass, affecting the skin even indoors. UVA reaches the dermis, destroys collagen and elastin, and causes wrinkles and sagging. Because the temperature is cool in spring, it is hard to feel the UV rays, making it a period when damage tends to accumulate without noticing.

To prevent pigmentation after sunburn, care within 72 hours immediately after UV exposure is important. This period is the "golden time" when melanin production becomes active, and sufficient moisturizing and intake/application of antioxidant ingredients (Vitamin C, Vitamin E) are effective. If you are already concerned about pigmentation, we recommend consulting a dermatologist. We propose treatments suitable for symptoms, such as topical medications like hydroquinone and tretinoin, and laser therapy.

### *[Evidence]* *The "Cosmetic Medicine Clinical Guidelines" of the Japanese Dermatological Association clearly state that UV measures are the most important in preventing spots and pigmentation. Also, according to the Japan Meteorological Agency's UV data, the monthly average of the daily maximum UV index in April in Tsukuba City reaches 5.0 to 6.0 ("moderate to strong"), a level where sunscreen measures are recommended. In my clinical experience as a dermatologist, as a result of neglecting UV measures from spring to summer, many people come for consultation about spots from autumn onwards.*