How long is the validity period of sunscreen? How long can sunscreen not be used after opening?

Sunscreen is a cosmetic, so it certainly has a shelf life. It is not recommended to continue using it once the shelf life has expired. So what is the shelf life of sunscreen? How long can it be kept after opening?

How long is sunscreen generally effective?

The shelf life of sunscreen is approximately two to three years. Within the two or three years of its shelf life, sunscreen can provide the best sun protection effect. After the shelf life, the sun protection performance of the sunscreen will gradually decrease until the sunscreen deteriorates, and the sunscreen will no longer provide the desired sun protection effect.

How long should you not use sunscreen after opening it?

It cannot be used after opening for half a year or a year. On the packaging of most sunscreens, there is an image of a bottle with an open lid, and words such as 6M or 12M are written on the image, which means that the sunscreen has a shelf life of only half a year or a year after opening. Once the shelf life expires, it is recommended not to continue using it.

What happens if you open your sunscreen for too long?

1. Loss of sun protection effect: If the sunscreen is opened for too long, the physical sunscreens such as titanium dioxide and zinc oxide will deteriorate, causing the sunscreen to deteriorate and the sun protection effect of the sunscreen to change.

2. Cause skin allergies: If the sunscreen is opened for too long, the effective ingredients will be lost and bacteria will grow seriously. If you continue to use it, it will easily burden the human skin, cause skin allergies or inflammation, and affect the skin condition.

What to do if your sunscreen is expired

1. Shoe polishing

If you wear leather shoes or have leather shoes at home, you can use expired sunscreen to wipe the leather shoes with a used towel or a soft-bristled toothbrush.

2. Sticky suction cup

Sometimes, in order to make it convenient to hang things at home, such as clothes or convenience bags, some small hooks like suction cups are hung on the wall. If it takes a long time, the suction cup may not have enough pressure and will not be able to stick and fall off. At this time, we can apply sunscreen on the hook and then hang the hook up. In this way, the suction cup will be very firm.

3. Clean handwriting

When writing, sometimes we accidentally make strokes on our hands, which are generally difficult to wash off. At this time, we only need to apply an appropriate amount of sunscreen to the area with strokes, massage with our hands for a while, and then wash it off with clean water.