More Evidence Why We Should Avoid Ultra-Processed Foods

by Denis Storey
February 29, 2024 at 12:56 PM UTC

New research highlights the dangers associated with ultra-processed foods, including heart-related death, common mental disorders, and diabetes.

Clinical relevance: New research highlights the dangers associated with ultra-processed foods, including heart-related death, common mental disorders, and diabetes.

  • The NOVA food classification system categorizes foods into four groups based on processing levels, with ultra-processed foods being the most concerning due to their assembly with additives and ingredients uncommon in home kitchens.
  • An umbrella review conducted by researchers emphasizes the consistent association between greater exposure to ultra-processed foods and adverse health outcomes across various studies.
  • Policy recommendations stress the importance of national dietary guidelines favoring unprocessed or minimally processed foods, along with measures like clear labeling, restrictions on advertising and sales, and fiscal incentives to promote healthier eating habits.

We all know by now that processed and ultra-processed foods are bad for us. But new research proves – once again – just how bad these foods are for us.

Research from the Deaken University Institute for Mental and Physical Health in Victoria, Australia, shows that diets loaded with ultra-processed foods come with a higher risk of at least 32 different illnesses. Specific examples of increased disease risk include:

  • A 50 percent greater risk of heart-related death.
  • A 48 percent to 53 percent higher risk of anxiety and other common mental disorders.
  • A 12 percent elevated risk of Type 2 diabetes.

And continued consumption of these foods increases the health risks, the researchers added. Ultra-processed foods account for nearly 60 percent of total daily energy intake in some higher-income countries. And they’re proliferating in low- and middle-income countries, the researchers observed.

Defining ultra-processed foods

University of São Paulo, Brazil researchers drafted the NOVA food classification system in 2016, which coined the term “ultra-processed foods.”

The methodology organized food into four categories based on the level of processing during production: 

  1. Unprocessed or minimally processed foods: This includes produce, milk, fish, eggs, nuts, and seeds. These foods undergo minimal – if any – changes during processing.
  2. Processed ingredients: This covers foods added to other foods and aren’t typically eaten alone. This includes salts, sugars, and oils.
  3. Processed foods: Processors produce these finished goods by combining foods from the first two groups. The changes made in this type of processing are relatively simple. Home cooks can replicate these changes, too. Foods in this category include jams, pickles, tinned fruit and vegetables, and homemade breads and cheeses.
  4. Ultra-processed foods: Foods in this final category are assembled with five or more ingredients. They also include additives and ingredients not typically found in home kitchens. This covers preservatives, emulsifiers, sweeteners, and artificial colors and flavors. These foods generally have longer shelf lives. Foods that fall into this classification include ice cream, ham, sausages, crisps, mass-produced bread, breakfast cereals, biscuits, carbonated drinks, fruit-flavored yogurts, instant soups, and some alcoholic beverages.

An ‘Umbrella’ Overview

Although researchers have worked for years to uncover the links between ultra-processed foods and adverse health outcomes, no one’s attempted an overarching evaluation.

“Undertaking such a comprehensive review has the potential to enhance our understanding of these associations and provide valuable insights for better informing public health policies and strategies. This is particularly pertinent as the global debate continues regarding the need for public health measures to tackle exposure to ultra-processed foods in general populations,” the authors wrote. “To bridge this gap in evidence and contribute to the ongoing discussion on the role of ultra-processed food exposure in chronic diseases, we did an umbrella review to evaluate the evidence provided by meta-analyses of observational epidemiological studies exploring the associations between exposure to ultra-processed food and the risk of adverse health outcomes.”

The researchers pored over 45 distinct pooled analyses. These included more than 9.8 million subjects and covered seven health parameters related to mortality, cancer, and mental, respiratory, cardiovascular, gastrointestinal, and metabolic health outcomes. In short, the researchers found that greater exposure to ultra-processed foods, “whether measured as higher versus lower consumption, additional servings per day, or a 10 percent increment, was consistently associated with a higher risk of adverse health outcomes (71 percent of outcomes).”

Policy Implications

An editorial accompanying the published research, drafted by professor Carlos A Monteiro and senior research fellows Eurídice Martínez-Steele and Geoffrey Cannon, throws doubt on the idea that our bodies can adapt to these foods. As such, policymakers and regulators must act quickly. The authors’ suggestions include:

  • National dietary guidelines that recommend varieties of unprocessed or minimally processed foods and freshly prepared meals and avoidance of ultra-processed foods.
  • Institutional food procurement that aligns with these guidelines.
  • Front-of-pack labels that clearly identify ultra-processed foods.
  • Restricting advertising and prohibiting sales in or near schools and hospitals.
  • And fiscal measures that make unprocessed or minimally processed foods and freshly prepared meals as accessible and available as, and cheaper than, ultra-processed foods.

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