“Adding salt makes water boil faster.”

It's a common kitchen practice to toss a pinch of salt into a pot of water, with many believing it will bring the water (Review) to a boil more quickly. This idea is a widespread culinary misconception, often passed down through generations of home cooks. While the intention might be to speed up meal preparation, the science behind it reveals a different outcome.

Scientifically, adding salt to water actually elevates its boiling point, a phenomenon known as boiling point elevation. This means that saltwater (Deals) needs to reach a slightly higher temperature than pure water before it will begin to boil. The dissolved salt ions interfere with the water molecules' ability to escape into the gas phase, requiring more energy—and thus a higher temperature—to overcome these interactions and initiate boiling. Although salt also lowers the specific heat capacity of water, meaning less energy is theoretically needed to raise its temperature, for the small amounts of salt typically used in cooking, this effect is negligible and doesn't counteract the increased boiling point. In fact, for a noticeable difference in boiling time, one would need an impractically high salt concentration, far beyond what's used for seasoning food.

So, why does this myth persist? One reason might be the visual effect of adding salt to hot water; the sudden appearance of bubbles as the salt dissolves can mistakenly be interpreted as the water boiling faster. Another factor could be the association of salt with cooking and the general desire to accelerate processes in the kitchen. Ultimately, the primary and most practical reason for adding salt to cooking water is to season the food, enhancing its flavor from the inside out (Review), rather than to shave precious seconds off boiling time.