The low carbohydrate, high fat (LCHF) diet is anything but a fad, Professor Tim Noakes said during his testimony before the Health Professions Council of South Africa on Friday.
"The diet has been around since 1852. It was the original diet and has stood the test of time," he said.
In Letter on Corpulence by William Banting published in 1863, the author was put on a LCHF diet and was the first person to report his experience, Noakes said.
Banting wrote: "I can now confidently say that quantity of diet may be safely left to the natural appetite and that it is the quality only which is essential to abate and cure corpulence."
Noakes also quoted physician Wilhelm Ebstein, who he called a "god of medicine", who in 1892 also prescribed a high fat, low carb diet.
He too said sugar should be entirely prohibited, and a moderate amount of fats should be consumed.
Noakes further referred to the book The Physiology of Taste, written in 1820, which found the second principle cause of obesity lay with starches and flours.
"This diet is not unconventional. It has been made unconventional by people who are not prepared to read the literature," he said.
"It's easier to shoot the messenger. And I have been shot."
Noakes - whose book The Real Meal Revolution promotes a low-carbohydrate, high-fat (LCHF) diet - was called before the council after a complaint was lodged by the former president of the Association for Dietetics in SA, Claire Julsing-Strydom.
The complaint was due to a tweet Noakes sent to a Pippa Leenstra after she asked him for advice on feeding babies and on breastfeeding.
The tweet read: "@ProfTimNoakes @SalCreed is LCHF eating ok for breastfeeding mums? Worried about all the dairy + cauliflower = wind for babies??" (sic)
Noakes advised her to wean her child onto LCHF foods, which he described as "real" foods.
The tweet read: "Baby doesn't eat the dairy and cauliflower. Just very healthy high fat breast milk. Key is to ween [sic] baby onto LCHF."
He is accused of giving unconventional and unscientific advice, and of unprofessional conduct for dispensing this via social media.
According to witnesses called by the HPCSA, a consultation was required before any diagnosis could me made or advice given.
Noakes on Wednesday used the hearing as a platform to explain what he considers to be the facts around the LCHF diet.
He insisted that SA "has lived a lie for 50 years" since the introduction of the US Department of Agriculture's food pyramid in 1977, which Noakes said led to an increase in the obesity rate.
"I just hope that the message will get out and people will ask why Noakes was victimised for telling the truth.
"That's what doctors have to understand. We got it wrong for 50 years. Let's change it."
The hearing continues.