Campbell was born in Margaretting. He was educated at Carshalton and in Neuwied. He qualified from St Bartholomew's Hospital and obtained MRCS, MBBS and M.D.. He married Nora Lacy. He worked as a physician and pathologist at North-West London Hospital and West End Hospital for Nervous Diseases. He was a Fellow of the Royal Anthropological Institute. He retired as physician in 1919. From 1918 to 1933, he was the editor of the Medical Press and Circular. Campbell was elected a Fellow of the Royal College of Physicians of London in 1896. Cambell was a member of the British Medical Association and contributed articles to the British Medical Journal. In 1904, Campbell authored a series of articles, The Evolution of Man's Diet in The Lancet journal. He also contributed articles to the book, A System of Diet and Dietetics which was positively reviewed in the Journal of the American Medical Association. Campbell authored the book What is Wrong With British Diet?, in 1936. Campbell argued that the British diet was too heavy in cereal foods, cooked vegetables and puddings which provided inadequate mastication. He believed that habitual consumption of soft "pappy" foods and "pultaceous puddings" caused undersized jaws and dental disease. He recommended a pre-agricultural diet that consisted of animal products and raw vegetables. He wrote that the "British diet errs mainly in containing an excess of cereals and starchy foods generally, and a dearth of animal and raw vegetable foods." Dr. Campbell wrote several medical research papers on mastication and the physiology of the jaw bones, jaw muscles and teeth formation in children and this is reflected in the series published in The Lancet, Observations on Mastication I-III in 1903. Here he examined the requirement for mastication in the development of the jaw in children. He was one of the first to make the link between a lack of chewing on tough foods during the formative "first" teething years of 6 months to 3 years leading to narrower jaws and compacted teeth – a phenomenon seen today with the higher prevalence of orthodontistry work in teenage children. His research work in this area took him down the path of establishing a business in 1925, after he retired from the medical profession, manufacturing natural teething biscuits which he called Bickiepegs in Welwyn Garden City. Made from cereal wheat the finger shaped product was designed to help babies cut the back and front teeth whilst exercising the jaw muscles, bones and gums. The company Bickiepegs Healthcare still exists 95 years on and bakes to the original recipe from its factory in Aberdeenshire. He died in Norwood.
