DeForest Clinton Jarvis (March 15, 1881 – August 18, 1966) was an American physician from Vermont. He is best known for his writings on the subject of folk medicine. He recommended a mixture of raw apple cider vinegar and honey that has variously been called switchel or honegar, as a health tonic. He promoted the use of vinegar to keep the acidity of the body more acidic than alkaline, which he believed treated medical problems like burns and varicose veins.