The benefits of a diet based on fresh foods

Technical formulator of Dietary Guidelines for the Brazilian Population explains the value of home cooking and comments on the US's reception of guidelines.

By Karina Toledo

Agência FAPESP – For anyone who wants to eat well, there are no solutions that do not involve freshly prepared meals, says Carlos Augusto Monteiro, a full professor at the University of São Paulo’s School of Public Health (FSP-USP) and technical formulator of the new Dietary Guidelines for the Brazilian Population.

“You don’t have to cook your own food,” Monteiro said. “Someone else can cook for you, but your meals shouldn’t be basically produced by the food industry.” The latest edition of the dietary guidelines, published in November 2014, is a partnership between FSP-USP’s Center for Epidemiological Research in Nutrition & Health (NUPENS) and the Health Ministry.

The previous edition, published in 2006, was organized around food groups and recommended portions.By contrast, the new guidelines emphasize the benefits of a diet based on fresh foods such as fruit, meat, vegetables and eggs, and minimally processed foods such as rice, beans and dried fruit. It emphatically rules out ultra-processed foods such as instant noodles, packaged snacks and soft drinks.

The Brazilian media paid little attention to the publication when it was launched, but it was widely noticed in the United States and praised by some of the foremost specialists in nutrition.

Marion Nestle, a professor at New York University (NYU), wrote in her blog Food Politics, “The guidelines are remarkable in that they are based on foods that Brazilians of all social classes eat every day, and consider the social, cultural, economic and environmental implications of food choices.”

Michael Pollan, a professor at the University of California (UC), Berkeley and author of Food Rules: An Eater’s Manual (2010) and In Defense of Food: An Eater’s Manifesto (2008), among other books, called the guidelines “revolutionary” because they “are actually organized around food (and meals!), not nutrients.”

According to Robert Lustig, a pediatric endocrinologist at the University of California, San Francisco (UCSF), “The US needs to follow Brazil's lead and stop talking about nutrients and start talking about food! This is a landmark document,” as reported in the Jan.-Feb. issue of World Nutrition, the journal of the World Public Health Nutrition Association.

In February, when the US dietary guidelines advisory committee’s report on the five-year revision was published with 571 pages of reviews of the scientific literature, commentators there recalled the Brazilian guidelines. A report posted to the Vox news website, for example, was titled “Brazil has the best nutritional guidelines in the world.”

In an interview with Agência FAPESP, Monteiro described how the NUPENS team gathered the scientific evidence used as a theoretical basis for the guidelines, with financial support from FAPESP and the collaboration of specialists from all over Brazil.

Agência FAPESP – How do the Dietary Guidelines for the Brazilian Population classify different kinds of food?
Carlos Augusto Monteiro – The guidelines classify foods into four groups according to the amount of industrial processing. The first category, which should be the basis of a healthy diet, consists of fresh produce, such as fruit and greens. The second consists of substances extracted from fresh produce or directly from nature and used for seasoning and cooking; examples include oil, fat, sugar and salt. The third category consists of products manufactured mainly by adding salt or sugar to natural or minimally processed foods. Examples include canned or bottled vegetables and fruit, as well as cheese and bread. Consumption of this group should be limited to small amounts as accompaniments or garnishes. The fourth category, which should be avoided, consists of ultra-processed foods, such as soft drinks, biscuits and packaged snacks. These products are formulations created by the modern food industry, with little or no real nutritional value and large amounts of oil, salt and sugar. They also contain many other substances derived from food extracts, elements of other organic materials, including modified amides, protein isolates, milk serum, hydrogenated fat, and an array of chemical additives. The additives used in the manufacturing of ultra-processed foods are designed to make them last almost indefinitely and make them as attractive as real food or more so.

Agência FAPESP – Why should ultra-processed foods be avoided?
Monteiro – Ultra-processing produces very low-cost food with significant acceptability, durability and convenience. This is achieved by means of highly sophisticated technological processes and the use of relatively cheap ingredients, such as sugar, fat, salt and additives. Ultra-processed foods have an intrinsically unbalanced nutritional profile, with lashings of sodium, sugar and unhealthy fat. Because of the processes and ingredients used, ultra-processed foods confuse natural controls of hunger and satiety, so that to some extent they promote obesity. They are designed to be “irresistible,” a quality frequently mentioned in the advertising for these products. Lastly, there’s the issue of the safety of food additives.

Agência FAPESP – Aren’t food additives safe?
Monteiro – Although the industry only uses legally permitted additives, the assessments on which permission is based are very limited and don’t take into account the long-term effects of additives or the effects of interactions between them. Recent research has shown, for example, that artificial sweeteners and emulsifiers, which are very common additives in ultra-processed foods, can alter the intestinal microflora and may destroy the layer of mucus that protects the intestinal epithelium, leading to a heightened risk of colitis, obesity, diabetes, and other chronic diseases. Given the exponential growth in sales of ultra-processed foods, hundreds of new additives enter the market each year. More rigorous regulation of food additives is urgently needed.

Agência FAPESP – The Brazilian guidelines have been hailed as an example by US journalists and experts. How do they differ from the latest update to the US dietary guidelines?
Monteiro – The current US dietary guidelines date from 2010. A new edition is due later this year. The current edition emphasizes, sometimes to the exclusion of all else, the scientific evidence obtained from fully controlled clinical trials, just like the procedure used by the health authorities to issue recommendations on new drugs, vaccines or surgical techniques. When you do that to food, you have to reduce it to the individual nutrients it’s made up of, such as proteins, iron, vitamins, fiber. The trouble with this approach is that it overlooks the many dimensions of diet and the mechanisms that relate diet to health. The cultural, social and environmental dimensions of diet, which directly or indirectly also influence health, are forgotten. The 2015 advisory committee’s report, recently issued for public comment, includes many improvements but still won’t make the US guidelines a useful tool for ordinary people.

Agência FAPESP – Is the diet of ordinary Brazilians becoming more similar to the typical US diet?
Monteiro – We’re in the middle of a transition here. Our population-based studies of Brazilian dietary patterns show that in 2009 the proportion of ultra-processed foods in the typical Brazilian diet corresponded to 28% of total calorie intake. In 2003 it was 23%, and in the 1980s it was less than 20%. This proportion is rising rapidly, but even now minimally processed foods and home cooking account for 70% of total calorie intake in Brazil. So we’re still on “the right side” of the divide, hence the significance of our dietary guidelines. It’s important to provide people with information since many have no idea of the implications of their dietary choices. They may have an inkling, at least as far as the impact on health is concerned. The guidelines show why consuming ultra-processed foods is also bad for society, for the environment and for biodiversity.

Agência FAPESP – What can you say about FAPESP’s contribution to the Brazilian dietary guidelines?
Monteiro – It was most important. Our leading specialist in anthropology was Canada’s Jean Claude Moubarac, who came to Brazil with a post-doctoral scholarship from FAPESP. As part of Maria Laura da Costa Louzada’s PhD project, we evaluated the impact of the consumption of ultra-processed foods on the quality of the Brazilian diet in terms of macronutrients and micronutrients. Another FAPESP PhD scholarship awardee, Carla Adriano Martins, made an essential contribution to another innovative component of the Brazilian guidelines, which was emphasizing meals actually preferred by ordinary Brazilians as a basis for its recommendations, including photographs of typical breakfast, midday and evening meals. When the production process was in its final stages, FAPESP also awarded a postdoctoral scholarship to Diana Celmira Parra Perez, a Colombian researcher interested in taking Brazil’s experience to her own country.