The Complex World of Ultra-Processed Foods: Understanding the Impact on Health
Ultra-processed foods (UPFs) are rarely out of the headlines. Research shows that eating high levels of these highly industrially processed foods is linked to poorer health outcomes, including cardiovascular disease, type 2 diabetes, and obesity.
How are UPFs currently classified?
Most commonly, experts rate how processed a food is using the NOVA classification framework. This method classifies foods into four groups:
- Group 1: Unprocessed or minimally processed foods.
- Group 2: Processed culinary ingredients.
- Group 3: Processed foods.
- Group 4: Ultra Processed Foods (UPFs).
First outlined in 1990, NOVA classifies “all foods according to the nature, extent, and purposes of the industrial processes they undergo.”
Although widely used over the past few decades, NOVA has some limitations:
Why the confusion?
When scientists look at the consumption of NOVA category 4 foods in large populations, the overall effect is negative — those who eat the greatest amounts have the poorest health outcomes.
- Chemical additives, such as colorants, emulsifiers, and preservatives. We still don’t know how these compounds influence the gut microbiome, but it’s likely that they have some effect.
- UPFs often have high levels of energy, sugar, saturated fats, and salt. When consumed liberally, all of these components can negatively influence health.
- UPFs are often energy-dense and scientifically crafted to be delicious and very easy to eat (hyperpalatable), making it very easy to take in excess energy very quickly. You could wolf down five ultra-processed brownies in the time it would take you to eat a single apple, for instance.
- Eating more of these convenient, processed foods could be displacing healthier whole foods that we should be eating more of.
UPF types and heart health
A recent study analyzed dietary and heart health information from more than 200,000 people in the United States. Overall, they found that total UPF intake was linked to poorer cardiovascular health.
Some UPFs were associated with higher cardiovascular risk, including:
However, other UPFs were linked to a reduced risk of cardiovascular disease, such as:
UPF types and diabetes
In 2023, scientists published a study including data from almost 200,000 people. This time, they assessed UPFs’ links to type 2 diabetes.
Compared with those who consumed the lowest levels of UPFs, those consuming the highest amounts had a 46% increased risk of developing type 2 diabetes during the study follow-up.
Some UPF categories were associated with lower diabetes risk:
Developing the ZOE Processed Food Risk Scale
- Energy density: How many calories per gram of food.
- Energy intake rate: How quickly you eat the calories.
- Hyperpalatability: This can lead to excess consumption.
- Non-culinary additives: These include artificial colors, sweeteners, and preservatives. We accounted for whether the European Food Safety Authority (EFSA), the Food and Drug Administration (FDA), or other official bodies deem them neutral or harmful.
- Unprocessed: This food is in its original form or close to its original form. Processing does not impact how healthy it is.
- No Risk: Minimal processing that poses no risk to health.
- Low Risk: The processing of this food has no or very low impact on its health.
- Significant Risk: The processing of this food may make it less healthy and could have a moderate impact on your health.
- Highest Risk: The processing of this food makes it less healthy and could have a high impact on your health.
This tool will empower people to make healthier choices for themselves and their families.