Two-thirds of an indigenous community have metabolic syndrome and are obese

The main reason is increasing consumption of processed foods and soft drinks, alongside sedentarism.

By Peter Moon  |  Agência FAPESP – Consumption of processed food and soft drinks, alongside sedentarism, is leading to a significant rise in cases of metabolic syndrome in the Xavante indigenous community living on the São Marcos and Sangradouro/Volta Grande reservations in Mato Grosso State, Brazil.

Out of a total population of 4,065 living on both reservations, 932 individuals aged 20 years or more were evaluated (457 men and 475 women). Two-thirds (66.1%) were found to have metabolic syndrome (MS), defined as a condition in which risk factors for cardiovascular disease and diabetes mellitus occur in the same individual.

The main components of MS are central obesity, systemic arterial hypertension, dyslipidemia, and abnormalities in glucose homeostasis.

The findings have been published in the journal Diabetology & Metabolic Syndrome. The study was part of Luana Padua Soares’s PhD research under a project supported by FAPESP. Soares is a professor of nutrition at the Federal University of Uberlândia (UFU).

The prevalence of MS was higher among women than among men. No fewer than 76.2% of women had MS, compared with 55.6% of the men in the sample. According to Soares, “abdominal or central obesity appears to play a key role in the genesis of MS, so the large proportion of Xavante women that are overweight may be one of the reasons for this higher prevalence of MS. Although our study did not measure physical activity, we noted that Xavante women tend to get less exercise than men.”

Sedentarism is indeed a possible explanation for the high prevalence of MS among the Xavante, but it is not the only one. Changes in diet are believed to be the main reason for the large number of cases of obesity, diabetes and related diseases. The indigenous people on these reservations are consuming more processed foods and soft drinks with high sugar content. “As I see it, many Xavante have unfortunately not yet realized the extent of the problem and the health hazard this change of diet represents,” Soares said.

Data on the Xavante for 1999-2004, she went on, show high levels of mortality (11.4 deaths per 1,000 inhabitants), especially among infants under one year of age (96.7 per 1,000 live births). “These rates are much higher than the averages for the Brazilian population,” Soares stressed. “Life expectancy is 61.7 years, close to the average for Brazil almost 30 years ago.”

Prevention strategy

If action is to be taken to try to halt or reverse the growth in MS prevalence among the Xavante, she added, priority should be given to prevention, especially via improved weight control and avoidance of metabolic alterations, taking into account specific ethnic, cultural, and anthropometric factors, as well as lifestyle. “A return to traditional practices, which were healthier, is one of the options, but would probably be complex and difficult,” she said. “The Xavante have changed their dietary habits and become less physically active in response to a number of socio-economic, cultural and environmental factors, including contact with non-indigenous society, loss of territory, depletion of natural resources, obstacles to traditional subsistence activities, and a decline in food diversity, among others.”

But are the Xavante an isolated case, or are they part of a wider epidemiological trend? “There aren’t many studies of MS prevalence among indigenous populations in Brazil,” Soares said. “The rate most similar to the Xavante’s is 65.3% for the Kaingang and Guarani in Rio Grande do Sul.”

Other studies of MS prevalence among indigenous populations have found much lower rates: 21.9% for the Suyá and 27.8% for the Khisêdjê, both in Xingu National Park, Mato Grosso State, and 35.7% for the population of Jaguapiru, an indigenous community in Dourados, Mato Grosso do Sul State. “Comparisons are difficult because of the significant ethnic, cultural and lifestyle differences, but there’s no question that the prevalence of MS among the Xavante is very high,” Soares said.

The article “Prevalence of metabolic syndrome in the Brazilian Xavante indigenous population,” by Soares, Amaury Lelis Dal Fabbro, Anderson Soares Silva, Daniela Saes Sartorelli, Luciana Ferreira Franco, Patrícia Chamadoira Kuhn, Regina Santiago Moises, João Paulo Botelho Vieira-Filho and Laércio Joel Franco (doi:10.1186/s13098-015-0100-x), can be read in Diabetology & Metabolic Syndrome 2015.