Because garlic contains a fair amount of fructose, it is highly recommended that you eat it in moderation. Too much fructose can definitely be bad for you, so you will need to make sure that you do everything you can to limit the amount you consume on a regular basis. Some of the other foods that are okay to eat in moderation due to their moderate fructose level includes spring onions, coriander, onions, and of course garlic.
As far as foods that are completely safe to eat, you can feel confident eating just about any type of fruit as well as such vegetables as shallots, spinach, and celery. All of these foods and many more are good for those who are on a low-fructose diet.