One clear-faced influencer will claim it’s their biggest skincare secret, and the top comments complain about the same trick not working for them. Some of Reddit’s most popular skincare posts will feature before-and-after photos evidencing the wonders of drinking more H2O, while its top memes and tweet screenshots mock this advice.

On one hand, it’s the most affordable skincare advice out there: water is easily accessible for most people, and drinking enough of it is already crucial to good health. Plus, it feels right, like you’re flushing out all the impurities that could clog up your pores. But will drinking more of it really make acne go away and smooth away your wrinkles?

“I’m one of those guys who thinks it’s a myth,” Dr. Cameron Rokhsar, a board-certified dermatologist and associate clinical professor of dermatology at Mount Sinai Hospital, said.

1. Your body is designed to tell you how much water you need

“Our body’s thirst mechanism is pretty robust,” Rokhsar said, noting that it’s unlikely someone who has access to clean water would ignore their body telling them they’re thirsty.

As for drinking more than the recommended eight glasses of water a day: Rokhsar said it won’t give you much, other than more frequent trips to the bathroom. “Our kidneys are pretty good at figuring out the concentration of our urine,” he said, noting how lighter urine just means there’s more water in your urine. “If you drink too much water, you’re gonna pee all that out anyway” – without any added benefits.

Plus, there are risks to drinking too much water. Your kidneys won’t be able to process all that fluid, which can lead to life-threatening conditions like hyponatremia. As long as your urine is pale yellow, you should already be getting enough water.

2. Swapping caffeinated and sugary drinks for water

One reason people’s skin clears up or gets smoother with more water is that they’re also cutting back on drinks like soda, sugary drinks, coffee or tea.

According to Rokhsar, sugar is “pro-inflammatory” and can exacerbate acne, while caffeinated beverages are diuretics and will dehydrate you.

What is often missing from quick social media posts is how drinking water fits into the person’s existing habits. If they’re swapping Coke or iced tea with water (as opposed to merely drinking more of it), they’re reducing the substances that can worsen their skin.

3. Moisturisation is the key to true skin hydration

If you routinely forget to drink enough water per day, you can grab one of those water bottles with the times marked on them. Drinking enough water every day is the baseline of healthy skin. It’s just not the magic cure for everything else.