Is UV radiation the cause of aging?! A woman's worst enemy, known as "photoaging."

Ultraviolet rays cause skin aging, a phenomenon known as "photoaging."

It's often said that you can tell a person's age by looking at their hands, and you can also get a good sense of how much aging is progressing by looking at their hands.

For example, let's compare the skin on the buttocks and the back of the hand of the same person. The skin on the buttocks, which is rarely exposed to sunlight, will likely be smooth, while the skin on the back of the hand, which is more exposed to sunlight, will probably have more wrinkles and sagging.
This is proof that ultraviolet rays are deeply related to skin aging. The real danger of ultraviolet rays lies not in the immediate redness or tanning, but in the gradual accumulation of skin changes that occur, in other words, "photoaging."

Photoaging is said to be proportional to the duration and intensity of exposure to ultraviolet (UV) rays. It is said that approximately 80% of skin aging in exposed areas such as the face and hands, which are often directly exposed to UV rays, is caused by photoaging.
As shown in the table below, the characteristics of the skin are clearly different when compared to natural aging.

		natural aging	photoaging
Appearance		It is smooth and shows a decrease in elasticity (firmness).	It's rough and has deep wrinkles and blemishes.
Skin texture		Almost normal	Severely deformed
epidermis	stratum corneum	Normal thickness	The thickness is uneven.
epidermis	melanocytes	Decreasing, morphology is almost uniform Melanin production is impaired.	Increase, morphology is non-uniform Melanin production is increased.
dermis	collagen	The thickness and orientation of the fiber bundles change slightly.	The thickness of the fiber bundle changes.

(References) Adapted from RM Lavker: Photodamage, p.123, Blackwell Sci., 1995, and AM Kligman: Aging and Skin, p.33, Seishi Shoin, 1986.

The risk of "photoaging" is increasing!?

The ozone layer that surrounds the Earth's atmosphere acts like a "spacesuit," protecting us from ultraviolet rays pouring down from space.
According to the Japan Meteorological Agency's ozone layer observation report, ozone levels in Sapporo and other areas are decreasing year by year, while ultraviolet radiation levels are said to be increasing.
That is why, for those of us living in this era, protecting ourselves from ultraviolet rays, which cause photoaging, has become a more important issue than ever before.