I see some claims about amazing health benefits being made, but when I look at the details they say it's because dragon fruit contains fiber, antioxidants, vitamins and minerals. These are things you can get in any fruit or vegetable, and it doesn't look like there's anything special in dragon fruit.
I found a nutritional analysis of it here:
http://www.healwithfood.org/nutrition-f ... nefits.php It's 87% water. If you read the text at the link it says that the seeds have a strong laxative effect, so watch out for that lol. But it seems like fiber is the main reason for it, which you can get from any other fruit.
For comparison, here's a nutritional analysis of strawberries, which are 91% water.
http://nutritiondata.self.com/facts/fru ... ces/2064/2 Click the dropdown box to change the serving size to 100 grams so it's comparable to the dragon fruit. Overall it looks like the strawberries have more nutrients than the dragon fruit does, but the dragon fruit surpasses it in some ways. But it's not a huge difference.
Here's an analysis for Florida oranges:
http://nutritiondata.self.com/facts/fru ... ces/1969/2 Remember to change the serving size to 100 grams for comparison purposes. The oranges are 87% water, just like the dragon fruit. The orange juice wins on Vitamin C and calcium, but the dragon fruit wins on some other things.
Overall it sounds like some of our ordinary fruits are more nutritious, but not enough to make a major difference. If you like dragon fruit then eat it, and if you think the plant is attractive or interesting to look at you can plant it. But if it doesn't really interest you there's no special reason to seek it out.