Recently published research links a high consumption of ultra-processed foods to increased risks of cardiovascular disease, colorectal cancer and death.
The findings add further evidence in support of policies that limit ultra-processed foods.
Two major studies published by The BMJ last week found links between high consumption of ultra-processed foods and increased risks of cardiovascular disease, bowel (colorectal) cancer and death.
The results provide more evidence in favor of policies that limit ultra-processed foods and instead advocate eating unprocessed or minimally processed foods to improve global public health.
They also point to the possibility of reformulating dietary recommendations around the world, paying greater attention to the degree of processing of foods as well as nutrient-based recommendations.
Ultra-processed foods include baked goods and packaged snacks, soft drinks, sugary cereals, and ready-to-eat or reheat products. They often contain high levels of added sugar, fat and/or salt, but lack vitamins and fiber.
Although previous studies have linked ultra-processed foods to higher risks of obesity, cholesterol, high blood pressure and certain cancers, few studies have assessed the association between consumption of ultra-processed foods and colorectal cancer risk, and results are mixed due to limitations of study design and sample sizes.
In the first new study, researchers investigated the association between consumption of ultra-processed foods and colorectal cancer risk in American adults.
Their findings are based on 46,341 men and 159,907 women from three large studies of US healthcare professionals. Their food intake was assessed every four years using detailed food frequency questionnaires.
Foods were grouped by degree of processing and colorectal cancer rates were measured over a period of 24 to 28 years, taking medical and lifestyle factors into account.
The results show that men in the top fifth of ultra-processed food consumption had a 29% higher risk of developing colorectal cancer compared to those in the bottom fifth of consumption. This remained significant after further adjustment for body mass index and diet quality.
No association was observed between overall consumption of ultra-processed foods and risk of colorectal cancer in women. However, higher consumption of ready-to-eat meat/poultry/seafood products and sugar-sweetened beverages among men – and mixed ready-to-eat/reheated meals among women – was associated with a increased risk of colorectal cancer.
In the second new study, scientists analyzed two food classification systems in relation to mortality – the Food Standards Agency’s Nutrient Profiling System (FSAm-NPS), used to derive the code-coded Nutri-Score label. color on the front of the package, and the NOVA scale, which rates the degree of food processing.
Their findings are based on 22,895 Italian adults (average age 55; 48% male) from the Moli-sani study, which studies genetic and environmental risk factors for heart disease and cancer.
The quantity and quality of food and drink consumed were assessed and deaths were measured over a 14-year period (2005 to 2019), taking into account underlying medical conditions.
The results showed that those in the top quarter of the FSAm-NPS index (least healthy diet) had a 19% higher risk of dying from any cause, and a 32% higher risk high in cardiovascular disease deaths compared to lower quarter (healthiest diet) .
The risks were similar when the two extreme categories of ultra-processed food consumption on the NOVA scale were compared (19% and 27% higher for all-cause and cardiovascular mortality, respectively).
A significant proportion of the excess mortality risk associated with poor diet was explained by a higher degree of food processing. In contrast, consumption of ultra-processed foods remained associated with mortality even after accounting for poor nutritional quality of the diet.
Both studies are observational and therefore cannot establish a cause. Limitations include the possibility that some of the risks are due to other unmeasured (confounding) factors.
Nonetheless, both studies used reliable markers of diet quality and took well-known risk factors into account, and the results support other research linking highly processed foods to poor health outcomes. health.
As such, both research teams say their findings confirm the public health importance of limiting certain types of ultra-processed foods for better health outcomes for the global population. The results of the Italian study also strengthen the possibility of reformulating dietary guidelines around the world, paying more attention to the degree of food processing as well as nutrient-based recommendations.
In a linked editorial, Brazilian researchers say no sane person wants foods that cause disease.
The overall positive solution, they say, is to make supplies of fresh, minimally processed foods available, attractive and affordable. And support national initiatives to promote and support freshly prepared meals made from fresh, minimally processed foods, using small amounts of processed culinary ingredients and processed foods.
“Passed, it will promote public health. It will also feed families, society, economies and the environment,” they conclude.
References:
“Association of ultra-processed food consumption with colorectal cancer risk in men and women: results from three prospective US cohort studies” by Lu Wang, Mengxi Du, Kai Wang, Neha Khandpur, Sinara Laurini Rossato, Jean-Philippe Drouin-Chartier, Euridice Martínez Steele, Edward Giovannucci, Mingyang Song and Fang Fang Zhang, August 31, 2022, The BMJ.
DOI: 10.1136/bmj.o1972
“Joint Association of Nutrient Profile of Foods by Front-of-Package Nutri-Score Label and Consumption of Ultra-Processed Foods with Mortality: A Prospective Moli-sani Cohort Study” by Marialaura Bonaccio, Augusto Di Castelnuovo, Emilia Ruggiero, Simona Costanzo, Giuseppe Grosso, Amalia De Curtis, Chiara Cerletti, Maria Benedetta Donati, Giovanni de Gaetano and Licia Iacoviello on behalf of the Moli-sani study investigators, August 31, 2022, The BMJ.
DOI: 10.1136/bmj-2022-070688