Henry Valentine Knaggs (14 February 1859 – 11 July 1954) was an English physician, anti-vaccinationist, naturopath and alternative health writer.
In 1889 he was resident surgeon at Boscombe Infirmary but his address, from 1883 until 1912 was 189 Camden Road, London NW where he was in general practice as a doctor.
The 1913 Medical Who's Who gives Knaggs' addresses as 41 Welbeck Street and Combe Edge, Langley Park, Mill Hill.
Examples are "Rheumatism and Allied Ailments," "The Cleansing Saline Fast," "The Misunderstood Microbe", "How to Prevent Cancer" and "Potatoes as Food and Medicine" (the last one still in print).
He was a naturopath and teetotaling vegetarian, an advocate of natural hygiene, and a long-time member of the National Anti-Vaccination League.
The Times obituary described him as "a man of great physical courage" who "had the gift of making little fuss aout the details of life".
Saying that he had lived to see many of his originally controversial views on diet and hygiene generally accepted, it concluded that "his loss will be deeply regretted by the thousands to whom his name is a household word".