Cape Town - The introduction of the US Department of Agriculture's food pyramid in 1977 led to an increase in the obesity rate, Professor Tim Noakes said at a hearing into his
"When we ask for dietary advice, we go to the US, which is the most obese nation in the world," he said.
"In the US, after 1976, obesity rates started to rise from 51 million to 111 million in 2010. A third of all Americans are rated obese."
Following the introduction of the pyramid, obesity rates rose in the US across all age groups which could not be related to genetics, he said.
"Something happened in 1977 to cause the increased obesity to occur. The Americans told people to consume more carbohydrates."
Since the rise in obesity rates, cancer had also followed suit, he claimed.
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 prompted by a tweet Noakes sent to a Pippa Leenstra after she asked him for advice on feeding babies and on breastfeeding.
Her 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.
His 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 the advice 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 started his testimony, using the hearing as a platform to explain what he considers the facts around the LCHF diet.
Noakes said he has read extensive studies and books – some not peer-reviewed – on low carbohydrate eating.
He said that five years ago he didn't know "anything" about the subject, but had since read extensively and had even established a nutrition section in his local library.
Non-peer-reviewed books were often considered worthless, he said, but this was no reason not to read them.
Noakes said peer-reviewers sometimes didn’t agree with what was said, or sent the books to reviewers who would reject them.
Everyone was keen to say obesity is a complex disease, the scientist argued.
"I don’t agree. There were low rates when people were eating the diet considered bad. This is the elephant in the room no one wants to address."