Physicians can't do magic. Dietary needs are to some degree individual but that doesn't mean that your physician necessarily knows what's best for you.

Healthy living is often about switching habits and that not something where physicians can help you much via a 15 minutes (or less) conversation.

If you suspect gluten insensitivity it can make sense to get tested by a physician but in many cases you just have to be aware of what's happening with you. How does your body react to different kinds of food? What stands in the way of changing your habits?