These are randomly generated diets built with foods from the USDA food database. Though there shouldn't be anything technically wrong with them, it's up to you to make sure you're satisfying your health needs, and consult a doctor before changing your diet if you think you have any health problems. More basically, don't follow a diet that's making you feel bad.
Also, make sure to check out the micronutrient stats under the cumulative meal stats. The generator tries to match the vegetables to make up for your micronutrient needs, but it's very dependent on what foods are stuck in the rest of your diet and isn't always successful. I'd therefore suggest taking a multivitamin, but I'm not a licensed nutritionist, licensed doctor, or licensed anything, so take my advice at your own risk.