Choosing a sponge for sensitive skin

A sea sponge has no hard edge anywhere on it. It is a skeleton of soft fibre, not a woven cloth with a hem or a plastic mesh with cut ends, and there is nothing in it to catch.

It also holds a great deal of water. A full sponge glides where a dry cloth drags, and most of the irritation people blame on soap is really friction.

After that it is a question of how fine the pores are. The finer they are, the less you feel the surface at all.

A loofah is not a sponge. It is a dried gourd, and it is coarse on purpose: it is made to lift dead skin, not to wash with. Even on robust skin, twice a week is plenty. On skin that is already sore it is the wrong tool.

A washcloth is gentle enough but does very little, and it has a woven edge and a hem, which are the two hardest parts of it.

A sea sponge sits between the two: soft when wet, no edges, and it lasts years rather than weeks.

Konjac sponges are made from a plant root and are sold for the same job. We do not sell them, so we are not going to pretend to be neutral about them.

What we can tell you is what ours do. A deep-water sponge, rinsed and dried properly, is still in use three or four years later, and it is the same sponge, not a replacement for a replacement.

You would expect a shop to push the expensive sponge, so here is the arithmetic rather than the assurance.

The deep-water sponges grow slowly under pressure and end up denser, and that density is why they last three to four times as long.

The silk sponge, every time. Not because the others would do anyone harm (they would not) but because it is simply the softest thing in the shop. Velvety is the word we use, and it is the right one.

It grows at sixty to seventy metres, where the water is cold and the pressure high, so it grows slowly and its pores end up so small that the surface is almost smooth.

You will read online that a bath sponge should be replaced every three or four weeks. We are not going to pretend that advice does not exist. What we can tell you is what happens to ours, looked after this way:

• Rinse it through with plenty of water after every use, until nothing is left inside it. Shampoo and shower gel left in a sponge are what shorten its life.
• Squeeze the water out and leave it somewhere with air around it, not sealed in the corner of the shower.
• Once or twice a month, soak it for a quarter of an hour in warm water (warm, not hot) with a spoonful of bicarbonate of soda.

Treated that way, a shallow-water sponge lasts a year to eighteen months and a deep-water one three to five years. You will know when it is finished, because it starts to fall apart.