When you shop for a swimsuit for your kid, don’t buy them a blue one. The simple reason: The color can make it difficult, even impossible, to see them underwater.

According to the CDC, drowning is the leading cause of unintentional death for children between the ages of 1 and 4, and nearly 400 children drown in swimming pools or spas every year in the US. And while there’s a lot more to swimming safety than the color of a bathing suit, why tempt fate?

The distortion of light caused by sunlight on a swimming pool can be more dramatic than you might think. Check out this video where Nikki Scarnati, an infant swimming resource instructor demostrates the point with her child. As Scarnati points out, her video is shot in calm pool water. Add in a bunch of other kids splashing around and some waves, and you could see how quickly a child could disappear underwater, even in bright sunlight.

A terrifying example of pool-blindness

If you’re up for a particularity gruesome real-world example of how hard it can be to spot a child in a swimming pool, consider the 2002 case of Paolo Alexander Ayala. The 7-year-old boy was reported missing after he attended a pool party in the affluent Los Angeles neighborhood of Holmby Hills.

Police conducted an extensive manhunt, and after two days, Ayala’s body was located: He’d been at the bottom of the backyard pool the entire time. The water was clear, and dozens of people had checked it, including trained police officers and LAPD detectives, but no one saw the boy’s body. He was wearing blue and white trunks.

So which color swimsuit should you choose for your child?

As for what color suit you should choose, the rule-of-thumb is simple: Make it bright. Lifehacker has covered bathing suit colors and safety before, pointing to the research done by aquatic safety company ALIVE Solutions. They tested a dozen suit colors for visibility in both a lake and a pool, and determined the most visible colors are neon yellow, neon green, and bright orange. Neon pink is a good choice for a swimming pool with a light bottom, but not as good a choice in a lake.

Another thing to think about: Contrasting colors. Chunky neon green trunks with a bright orange swim top might not be the most fashionable color combination, but it’s a safer choice than a suit that matches the color of the bottom of the pool.

Suit color is no substitute for water safety

Wearing a bright bathing suit is great, but if you want to keep your child safer in the water, always keep watch over them, use lifejackets as appropriate, and, for god’s sake, teach them how to swim. Infants can learn to turn over on their backs if they fall into water, and children as young as one year old can benefit from swimming lessons. There is no excuse not to do this.

Taking your children anywhere near any kind of water, even a kiddy pool or fountain, involves a measure of risk, so familiarize yourself with basic water safety. Don’t let them swim anywhere unfamiliar or even remotely dangerous, and keep a close watch, even if there are lifeguards and other adults around.