A study suggesting Indigenous children from Saskatchewan and Manitoba were healthy when they were sent to residential schools undercuts government justification for nutritional experiments at the time.

Researchers also say it suggests the schools set the stage for health problems plaguing First Nations today.

Paul Hackett, a researcher at the University of Saskatchewan, said he and two others analyzed the body mass index of more than 1,700 children entering the schools between 1919 and the 1950s. The children's records, which are public, were meticulously kept on microfilm.

They detailed the weight, height and sex of the youngsters sent to a residential school in Brandon, Man., and to two others in Saskatchewan.

The team found 80 per cent of the children were at a healthy weight — better than the average Canadian child today. The findings were published in the International Journal of Circumpolar Health.

"All that suggests they were healthy, on the whole," Hackett said Tuesday. "That was somewhat surprising to me largely because of the thought that the Great Depression would have had some impact on health, that access to food might have been less.

"But they were coming out of their communities quite healthy, indeed much healthier than we see today."

The analysis, published in the International Journal of Circumpolar Health, suggests the residential school experience is directly linked to health problems such as obesity and diabetes, which disproportionately affect Indigenous people today, Hackett said.

Previous work by one of the researchers suggests diabetes was unknown among Indigenous people before 1937.

"There are many, many different factors, but certainly residential schools are certainly right up there as being one of the main factors in that loss of traditional food and loss of health," Hackett said.

"If there is a nutritional problem, it's probably coming out of the residential schools experience."

About 150,000 First Nations, Inuit and Métis children were taken from their families and forced to attend government schools. The last school closed outside Regina in 1996.

'If there is a nutritional problem, it's probably coming out of the residential schools experience.' - Paul Hackett, University of Saskatchewan

The Truth and Reconciliation Commission estimated at least 6,000 children died in the schools. The commission's final report said they were poorly heated, poorly ventilated and "the diet was meagre and of poor quality."

Murray Sinclair, who led the commission, said the schools were so poorly funded that they couldn't afford to properly feed the children.

"We heard stories ... that children were being fed rancid meat, being fed poorly prepared foods and generally unhealthy foods," he said.

It was in stark contrast to their lives before they were taken from their parents, he said.

"Survivors told us they felt loved. They felt well taken care of. They felt well nourished," Sinclair said. "It was at the schools that they began to feel the harshness of starvation."

It left an indelible mark which was passed on through generations, he said.

Some hoarded food, a practice that they carried into adulthood, Sinclair said. Others used food to punish their own children, repeating their own experience as kids.

The federal government knew nutrition was an issue, he said. Experiments with vitamins and enriched flour divided children at one school into two groups — one received vitamin, iron and iodine supplements and the other didn't.

The children who got the supplements saw their health improve, but the government wasn't interested in expanding the benefit to all, Sinclair said.

"It started the cycle of poor nutrition and poor eating practice and poor food purchasing practices very early on," he said.

"It maintained that for many generations and still continues today."