The poster can be found in almost every Canadian school: A rainbow representing the food we should be eating.

Green for vegetables. Yellow for grains. Blue representing dairy and red for protein.

But a Canadian researcher who helped Brazilians rethink how they eat says Canada's Food Guide should stop focusing on the four food groups but should instead look to eliminating processed food.

Earlier this week the Senate released a report on Canada's obesity crisis. The report, titled Obesity in Canada, pushes for a tax on sugary drinks, a ban on food and drink advertising aimed at children and government subsidies for healthy food.

It also makes 21 recommendations in total for dealing with Canada's obesity crisis, including a call for the federal government to rewrite Canada's food guide without any input from the food and beverage industries.

Emphasis on fresh food

Jean-Claude Moubarac, a researcher in the nutrition department at the University of Montreal, said Brazil's food guide isn't based on the four food groups like in Canada, but instead looks at how food is processed.

Canada's Food Guide is arranged as a rainbow, with fruits and vegetables making up the largest component. (Health Canada)

"It's based on the type of processing and the observation that people who consume more fresh and minimally processed food, they have the best diet," he told CBC's All in a Day.

The Brazilian guide, released in 2014, says the cornerstone of people's diets should be fresh, unprocessed food. It limits the use of oils, salt and sugar and recommends people avoid ultra-processed foods made with refined flours, sugars and starches.

Moubarac said that rules out chips, most frozen foods and sugary drinks.

It's a guiding principle he thinks Canada could learn from.

"In Canada we're grouping together things like sausages and chicken within the same group. We want to orient people into choosing the best quality of food that is out there. These are foods that are close to nature," he said.

The South American country's guide also looks at lifestyles. It moves beyond a do and don't list and calls for people to cook their own meals from scratch and eat with friends and family.

The Canadian Taxpayers Federation and the Canadian Beverage Association are opposed to a tax on sugary drinks advocated by a Senate committee. (Sam Hodgson/Reuters)

Food industry shut out from talks

"[Ready-made food is] convenient maybe at the moment because you don't have to cook but the [health] costs associated with these products are very high," Moubarac said.

The Brazilian guide also teaches people to be critical of food advertising.

When Brazil was rethinking its food guide Moubarac said the food industry wasn't part of the initial consultation. They were only allowed to weigh in during the public consultation stage.

"Now we see some researchers who are linked to the industry who are heavily criticizing the science behind the food guide. But if you look worldwide the Brazilian guide has been said to be one of the best models in the world," he said