Watermelon might be a summer fruit, but you tend to be able to find it all year round and you really ought to take advantage of its availability because, as it turns out, watermelon is incredibly good for you. So what are the health benefits of watermelon? Well, for one thing, it can help lower blood pressure in the obese. It’s also a natural diuretic that can help hydrate your body. It’s also a great sweet treat that’s still incredibly low in calories, and practically free from cholesterol and fat.