Ultra-Processed Foods Linked With Heart Disease, Bowel Cancer and Death

The findings add more evidence in support of policies that limit ultra-processed foods.

Two large research studies published by The BMJ last week found links between high consumption of ultra-processed foods and increased risk 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 the consumption of unprocessed or minimally processed foods to improve global public health.

They also highlight the opportunity to reformulate dietary guidelines around the world, paying greater attention to the degree of processing of foods along with nutrient-based recommendations.

Ultra-processed foods include baked goods and packaged snacks, carbonated beverages, sugary cereals, and ready-to-eat or heated products. They often contain high levels of sugar, fat, and/or salt, but lack vitamins and fiber.

Although previous studies have linked ultra-processed foods with increased risks of obesity, cholesterol, high blood pressure, and some types of cancer, few studies have evaluated the association between ultra-processed food intake and colorectal cancer risk, and Results are mixed due to limitations in study design and sample sizes.

In the first new study, researchers investigated the association between ultra-processed food consumption 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 health professionals. Their dietary intake was assessed every four years using detailed food frequency questionnaires.

The foods were grouped by degree of processing, and colorectal cancer rates were measured over a period of 24 to 28 years, taking into account medical and lifestyle factors.

The results show that men in the highest quintile of ultra-processed food consumption had a 29% increased risk of developing colorectal cancer compared to those in the lowest quintile of consumption. This remained significant after additional adjustment for body mass index and diet quality.

No link was seen between overall consumption of ultra-processed foods and colorectal cancer risk among women. However, higher consumption of meat/poultry/seafood and ready-to-eat products and sugar-sweetened beverages among men, and mixed ready-to-eat/heat dishes among women, was associated with an increased risk of colorectal cancer.

In the second new study, scientists looked at two food classification systems in relation to mortality: the Food Standards Agency Nutrient Profile System (FSAm-NPS), used to derive the label front-of-package color-coded Nutri-Score, and the NOVA scale, which assesses the degree of processing of foods.

Their findings are based on 22,895 Italian adults (average age 55; 48% men) from the Moli-sani Study, which investigates genetic and environmental risk factors for heart disease and cancer.

Both 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 highest quarter of the FSAm-NPS index (least healthy diet) had a 19 percent increased risk of death from any cause and a 32 percent increased risk of death from cardiovascular disease compared with the lowest fourth. low (healthier diet) .

The risks were similar when the two extreme categories of ultra-processed food intake 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 a poor diet is explained by a higher degree of food processing. In contrast, intake 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 cause. Limitations include the possibility that some of the risks are due to other unmeasured (confounding) factors.

However, both studies used reliable markers of diet quality and took into account well-known risk factors, and the findings support other research linking highly processed foods with poor health outcomes.

As such, both research teams say their findings support the public health importance of limiting certain types of ultra-processed foods for better health outcomes in the global population. The results of the Italian study also reinforce the opportunity to reformulate dietary guidelines around the world, paying more attention to the degree of food processing along with nutrient-based recommendations.

In a linked editorial, the Brazilian researchers argue that no sensible person wants food that causes disease.

The overall positive solution, they say, includes making fresh and minimally processed food supplies available, attractive and affordable. And sustain national initiatives to promote and support freshly prepared meals made from fresh and minimally processed foods, using small amounts of processed culinary ingredients and processed foods.

“Enacted, this will promote public health. It will also nurture families, society, economies and the environment.”

References:

“Association of ultra-processed food consumption with colorectal cancer risk among men and women: results from three US prospective 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 Food Nutritional Profile by Front-of-Package Label Nutri-Score and Ultra-Processed Food Intake with Mortality: Moli-sani Prospective 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