Newton was born at St. Christopher in the West Indies in 1767. Newton was a patient of physician William Lambe. He was inspired by the vegetable and distilled water diet of Lambe. Newton was married to Cornelia Collins. In 1811, Newton authored Return to Nature: Or a Defence of the Vegetable Regimen. Newton's book was written to popularize the research of William Lambe. He promoted a "regimen of distilled water and vegetable diet." He believed that vegetables are the natural food of man and animal flesh is unhealthy and unnatural.
Newton recommended people to utilize distillation apparatus for their water. He resided at Chester Street, Belgravia and argued that the water from the River Thames was polluted by "animal oil" and "septic matter". His diet was ovo-lacto vegetarian and consisted of fruits, vegetables, raisins, toasted bread, distilled water, eggs, milk and potatoes. Twenty-five people were practicing the diet in 1811, including seven from Newton's own household and all reported good health. Newton's book inspired John Snow to adopt the diet.
Newton met Percy Bysshe Shelley during 1812-1813 and influenced his views on vegetarianism. Historian Keith Thomas has noted that Newton's Return to Nature "provided much of the basis" for Shelley's book, A Vindication of Natural Diet.
Newton wrote a series of articles in The Monthly Magazine in 1812 which mention vegetarian dieting and the zodiac. Newton was a Zoroastrian and discussed the subject with his friend Thomas Love Peacock, in 1813. However, he did not write about the subject. Historian Stuart Curran has written that Newton's "vegetarianism was both radical in its political implications and extraordinarily learned in its sources. Newton was obviously aware that both Zoroastrian and Indian religion enjoined a vegetable diet, but he grafted to his amalgamation a primitive zodiacal astrology."
- Cameron, Kenneth Neill. (1970). Shelley and His Circle: 1773 - 1822, Volume 3. Harvard University Press. p. 254. ISBN 978-0-674-80611-5
- Thomas, Keith. (1983). Man and the Natural World: A History of the Modern Sensibility. Pantheon Books. p. 296. ISBN 978-0394727127
- Vinten-Johansen, Peter et al. (2003). Cholera, Chloroform, and the Science of Medicine: A Life of John Snow. Oxford University Press. pp. 39-41. ISBN 978-0195135442
- Ruston, Sharon. (2005). Shelley and Vitality. Palgrave. pp. 83-89. ISBN 978-1-349-51409-0
- Preece, Rod. (2008). Sins of the Flesh: A History of Ethical Vegetarian Thought. UBC Press. p. 13. ISBN 978-0-7748-15093
- Hodgart, Patricia. (1985). A Preface to Shelley. Routledge. p. 182. ISBN 978-0-582-35369-5
- Thomas, Keith. (1983). Man and the Natural World: A History of the Modern Sensibility. Pantheon Books. p. 296
- Cameron, Kenneth Neill. (1970). Shelley and His Circle: 1773 - 1822, Volume 3. Harvard University Press. p. 234-244. ISBN 978-0-674-80611-5
- Curran, Stuart. (1975). Shelley's Annus Mirabilis: The Maturing of an Epic Vision. Huntington Library Press. p. 88. ISBN 978-0873280648
- Lafayette B. Mendel. (1904). Some Historical Aspects of Vegetarianism. Popular Science Monthly 64: 457-465.