Can You Lose Weight By Sunbathing?

It's an almost standard summer image, something familiar from almost every form of summer media. Start any movie or crank up any song about summer and you'll hear all about catching some sun. In movies this usually translates into bathing suit-clad bodies lined up on the beach, wearing sunglasses, with arms and hands behind their heads as they soak up all the sun they can.

Most of the time these aren't just smiling and happy. They're slim, too. It's almost as if laying out under the sun is part of why they're so slim, or at least that's how it feels. But is there anything to the idea? Or is it just one of those ideas we come up with that don't end up bearing fruit in the real world?

Unfortunately, it turns out to be the latter. Sunbathing doesn't burn calories, no matter how much of a sweat you work up while you're laying out. At least you won't burn any more calories laying out in the sun than you do laying around inside, according to AZ Central. Your body is always burning calories to fuel internal processes and keep you alive. But that's about all the burn you're going to feel while you're sunbathing. Unless you're out too long, that is.

There is a common misconception that sweating more means you're burning more calories. But, as Men's Health explains, that's not true either. Sweating just means you're moving toward dehydration. And while working up a sweat through exercise means that you're losing that fluid because your body is heating up as it works, any weight loss you see (after drinking water again) is a result of the effort you put in, not the sweat. It's the reason insulated running suits don't actually do anything for weight loss.

The idea that you can lose weight through sunbathing is probably linked to the idea that sweating is a sign you're burning calories. But there's an even bigger flaw in the idea, other than the fact that a sweaty workout isn't always an effective one. When you sweat because of your environment — such as a lounge chair on a hot, sunny day — you're not even getting the weight loss benefits of a basic workout. 

Houston Methodist explains that we sweat on hot days because the sun is driving up our body temperatures. In an effort to avoid overheating and the serious complications it causes, your body breaks out in a sweat. As the sweat evaporates, it takes some of your body heat with it. There's no extra calorie burn, nor fat loss. So if you want to lose weight under the sun, grab a yard game or go for a swim and get your body moving.