Is anxiety relief by natural care effective?

Depends what kind: There are many "natural care" ways of helping anxiety -- and what's effective for one person may not be for another. Also it depends on what kind of anxiety you're talking about. For instance, pharmaceuticals are usually needed to deal with anxiety from alcohol or drug withdrawal. Still, whole foods diet, meditation, tai chi, some herbals, aromatherapy and classical homeopathy can be helpful.

Not that I know of: As a physician, I have very little knowledge about natural treatments. I have spent decades learning and refining my knowledge of medicine and psychiatry, and i believe the best treatments for clinical anxiety is a combination of prescription medications, psychotherapy, and lifestyle changes.