Demystifying food processing: The NOVA system
The NOVA food classification system, developed by scientists in Brazil, categorizes all food into four groups based on the extent and purpose of industrial processing. This system offers a clear framework for understanding whether a food is ultra-processed:
- Group 1: Unprocessed or Minimally Processed Foods. These are natural foods, like fruits, vegetables, meat, and eggs, that have been minimally altered (e.g., washed, frozen, or ground) to make them edible or safe to store, with no added ingredients.
- Group 2: Processed Culinary Ingredients. These are substances derived from Group 1 foods through processes like pressing, refining, or grinding. Examples include vegetable oils, butter, sugar, and salt.
- Group 3: Processed Foods. These are made by adding Group 2 ingredients (salt, sugar, or oil) to Group 1 foods. Tinned vegetables with added salt, canned fish in oil, or simple breads fall into this category. These are essentially simple industrial versions of what can be prepared at home.
- Group 4: Ultra-Processed Foods (UPF). These are formulations made from food substances extracted or derived from foods, often combined with additives like flavorings, emulsifiers, sweeteners, and cosmetic agents not typically used in home cooking. Products like sweetened cereals, sodas, instant noodles, and many ready-made meals are classified as UPF.
Is your tinned food processed or ultra-processed?
So, where does tinned food fit in? A can of plain chickpeas, black beans, or corn with just water and salt is a classic example of a processed food (Group 3). The canning process involves heat sterilization to preserve the food and make it shelf-stable. While some heat-sensitive nutrients like vitamin C may be slightly reduced, most minerals and fat-soluble vitamins remain intact. In fact, the heating process can sometimes even increase the bioavailability of certain antioxidants, such as lycopene in tomatoes.
The line is crossed when a tinned product contains a long list of unfamiliar, industrial ingredients. For example, a ready-to-eat canned pasta meal or certain canned soups may contain stabilizers, flavor enhancers, and preservatives beyond what you would use at home. These complex formulations push the product into the ultra-processed category (Group 4).
Comparing processed and ultra-processed tinned foods
Understanding the distinction is crucial for making informed choices. The ingredients list is your best tool. If it's short and contains recognizable items, it's likely a processed food. If the list is long and features unfamiliar chemical names, it's probably ultra-processed.
| Feature | Processed Tinned Food (e.g., plain canned beans) | Ultra-Processed Tinned Food (e.g., canned stew) |
|---|---|---|
| NOVA Group | Group 3 | Group 4 |
| Ingredients List | Short and recognizable (e.g., beans, water, salt) | Long, with unfamiliar industrial additives and cosmetic agents |
| Nutritional Content | Generally retains most nutrients, potentially with some added sodium | Often high in added fats, sugars, and salt; lower in fiber and micronutrients |
| Convenience | Ready-to-eat, but may require draining/rinsing | Often a complete, ready-to-heat-and-eat meal |
| Health Impact | Can be part of a healthy diet, particularly if rinsed to reduce sodium | Excessive consumption is linked to higher risk of obesity, diabetes, and heart disease |
The nutritional and health perspective
From a nutritional standpoint, the simplicity of plain canned foods can be a major advantage. They offer an affordable and accessible way to increase your intake of nutrient-dense foods like fruits, vegetables, beans, and fish. Rinsing plain canned vegetables and beans can significantly reduce their sodium content, addressing a common health concern.
Conversely, excessive consumption of ultra-processed foods, regardless of whether they come in a can, is associated with a higher risk of various health issues. These foods are engineered to be hyper-palatable, which can encourage overconsumption and contribute to weight gain. The cocktail of additives and unbalanced nutrient profiles are key differentiators from simply processed whole foods.
Practical steps for making healthy choices
- Read the ingredients: Don’t be misled by front-of-package health claims. Turn the can over and read the ingredients list. The shorter and more recognizable the list, the less processed the food.
- Rinse and drain: For plain canned vegetables and pulses packed in brine, rinsing and draining before use can help to wash away up to 41% of the sodium.
- Look for alternatives: Choose fruits canned in 100% juice or water, rather than heavy syrup. Look for no-salt-added or low-sodium vegetable options.
- Be aware of BPA: Some canned goods are lined with bisphenol A (BPA), a chemical that may migrate into food. While evidence is mixed, many brands now offer BPA-free packaging.
Conclusion
The question of whether tinned food is ultra-processed is not a simple yes or no; it depends on the specific product. Plain canned fruits, vegetables, and pulses are simply processed foods that can be a convenient and nutritious part of a balanced diet. However, if a tinned product contains a long list of unfamiliar, industrial ingredients and additives, it falls into the ultra-processed category and should be consumed in moderation. By checking the ingredients and making thoughtful selections, you can use canned goods as a healthy and convenient staple in your kitchen.
For more information on the NOVA system and processed foods, refer to resources from reputable health organizations like the British Heart Foundation.
