Those horizontal rows of lines above the eyebrows are quite common in those who ‘raise their eyebrows’ frequently when making facial expressions. The frontalis muscle is responsible for this movement which in turn creates creases and folds on the forehead.
As with other facial expressions, repeated action can cause lines to become permanent wrinkles on your forehead. Many factors can worsen the appearance of these wrinkles. Genetics is one of them so if your parents have these lines, you’re most likely to have them too. Ageing is another factor. As we age, we lose collagen and elastin in the skin. This reduces the ability for our skin to “bounce back” quickly to its original state after a facial expression is made. Over time, these temporary lines tend to become permanent wrinkles. Smoking can also make forehead lines worse. That is because nicotine causes blood vessels to narrow. This reduces oxygen flow and nutrients to the skin, thus weakening it.
As forehead wrinkles are typically what we will refer to as expression lines due to repetitive facial muscle movements, the use of neurotoxin like Botox or Xeomin is the most common option of treatment. They have been proven to be very effective in relaxing the treated facial muscles and thereby reducing the intensity of these related muscle movements. Over time, this could reduce the visibility of forehead lines.