The first time I used an outdoor shower in the middle of a rainforest, my shampoo had never worked better. The lather was perfect, the rinse was clean with no build-up to be seen. I later learned about the varying mineral content in water across regions, and how this can affect how cleansing ingredients work.
Hard water is water that is high in mineral content, particularly calcium and magnesium. These minerals can interfere with the surfactants in your shampoo and hinder their ability to lather. In addition, these interactions can build up on your hair and prevent a clean rinse. Depending on the degree of water hardness, some may notice weaker hair strands or a rougher hair appearance due to mineral deposition, versus hair treated with deionized (or soft) water.
If you think hard water may be the cause of unpredictable hair days, here are some ways to minimize its effects:
- Use a shower filter. Most hardware stores carry filtered shower heads that are easy to install with refillable filters that can be changed every 6 months.
- Look for chelators in your shampoo. On a label, this would show up as disodium or tetrasodium EDTA, sodium phytate, sodium gluconate, trisodium ethylenediamine disuccinate or tetrasodium glutamate diacetate. These bind to the metals found in hard water that would otherwise interfere with a shampoo or body wash performance.
- Try a shampoo bar. These are typically concentrated in surfactants and as a result, can work well in hard water. Ideally, look for one with a chelator.