If you are going to invest on quality bed sheets, then one of your priorities will certainly be keeping them in pristine condition. Even the best fabrics can, if not treated correctly, suffer from the wear and tear of repeated usages. If you do have a good product, however, it is relatively simple to guarantee that it retains its best features for a very long time. Here is how you can do it.
1 - If you wear makeup, make sure to remove it before going to bed
This is actually a good tip for your skincare as well. Almost all makeup includes emulsifiers and thickeners in its composition. This means that even if it doesn't leave a visible stain, residual makeup will trap oils and moisture in the fabric, facilitating the chemical processes that end up yellowing the sheets.
2 - If you do stain the sheets, clean them immediately
You don't even have to wash them. Just get a cleaning rag, or a sponge, a very small amount of dish soap, and attack small spots or stains immediately. Dish soaps are essentially surfactants, which means they break the tension between solids. This means it will keep the stains from setting, but won't work as well if they are already set. If you act quickly, you may not even have to remove the sheets from bed at all!
3 - Wash your sheets (more) regularly
This may seem like an obvious recommendation, but the truth is white sheets need to be washed more regularly than others. Once a week is ideal. You leave a lot of yourself in your sheets while you sleep. Sweat, dead skin cells. All of this is removed by washing, of course, but if you let it accumulate, white sheets will start to yellow. This yellowing can be removed, of course, but prevention is much easier.
4 - Do not use bleach
It seems like a good idea. Bleach whitens fabric, after all. The problem is that the yellowing of white sheets is produced by protein-based stains. Chlorine bleach reacts in a different way to protein than it does to other elements, and it will make those stains even more yellow. There are whiteners available in the market that are appropriate for white sheets. You will find them in any grocery store. Vinegar, lemon or baking soda will also work wonders.
5 - Air dry if possible
This doesn't affect the colour directly, but it is quite decisive. Tumble dryers are aggressive on the fabric, and air drying will keep your sheets looking and feeling comfortable and new for a lot longer. A worn-out fabric may technically be as white as a pristine one, but it won't look like it to the naked eye.