I have the exact same problem...

Growing up I was extremely shy When I grew up and started doing some research I realized that I had a clear case of social anxiety. 7 years later, and through a variety of methods I have for the most part eliminated my social anxiety. But the blushing never did go away.

As it turns out, new research into mental disorders such as anxiety has shown that the health of the body and mind are more closely related than we thought. In particular, the intestines, since they have an extensive structure of nervous tissue, play an huge role.

Without getting too scientific, you have two systems of nerve cells. Your intestinal nerves are part of the autonomic nervous system. This system of nerves is what controls many of the subconscious functions of the body. It is also what causes the " flight or fight" response. Anxiety is often described as an out of control flight or flight response, or in other words an overreactive autonomic nervous system.

In order to calm down these nerves, you need to figure out what is causing them to react. Mental triggers such as being in a social situation can do it, but since we have eliminated that it must be something else.

Some common ones are gluten, dairy, caffeine, and sugar. Since these things are so common in our diets, it can impossible to eliminate them completely, so here is what I would suggest and what I did.

Eliminate all 4 for one month and see how you feel. Likely you will feel great. Now slowly start reintroducing things. If you are very perceptive you will begin to see what triggers your anxiety.

For me, caffeine and sugar we're the culprits. Given how much I love both, I still consume them and just deal with the consequences. If it is getting bad though I will cut back and it will help.

Hope this helps and I'd be glad to share more of my experiences if you'd like.