It’s also worth noting that seasonal stress can cause greasier hair, too. “It’s the time of year that stress levels are high, and in turn that increases the levels of cortisol in the body. As a result, oil production once again increases, creating an oilier environment for both the hair and scalp,” she says.

So what’s the solution? Interestingly, Onuoha advises against washing your hair more regularly because it’s counter-effective. “It might seem like a natural response, but washing hair more often will dry out the scalp, leading to the production of more sebum,” she explains.

Instead, she recommends using a hydrating shampoo that’s formulated without sulphates – an ingredient that can strip away natural oils, causing it to overproduce oil. “I would also recommend investing in a clarifying shampoo to help remove the build-up of sweat, pollution and dead skin cells, all of which can lead to greasy hair,” says Onuoha.

This is why your hair might be getting greasier more quickly during the winter, according to a trichologist