Infrared cooking can be bad for you because it increases the risk of a person developing cancer due to the infrared cooking method.
Just like microwaves cook through microwaving the food which is what heats the food up that can too be bad for your health.
However infrared cooking and microwave cooking are both relatively safe cooking methods and have been used for quite some time.
I would not really worry about the health effects of cooking with infrared or cooking with microwaves as many people do cook using those methods and have stayed healthy.
I use my infrared cooker a lot as well as my microwave and never had or have so far any health issues.
I'm not worried about it either way.