Formerly obese, he is also known for being the first to popularise a weight loss diet based on limiting the intake of carbohydrates, especially those of a starchy or sugary nature.

[3] He undertook his dietary changes at the suggestion of Soho Square physician William Harvey, who in turn had learned of this type of diet, but in the context of diabetes management, from attending lectures in Paris by Claude Bernard.

[3][4] In the early 19th century, the family business of William Banting of St. James's Street, London, was among the most eminent companies of funeral directors in Britain.

[5] In 1863, Banting wrote a pamphlet, called Letter on Corpulence, Addressed to the Public,[6] which contained the particular plan for the diet he followed.

"My kind and valued medical adviser is not a doctor for obesity, but stands on the pinnacle of fame in the treatment of another malady, which, as he well knows, is frequently induced by [corpulence]."

[9] Banting is buried alongside his wife and daughter at Brompton Cemetery, London, England.