What Exactly Are Humectants?
Humectants are substances added to food, cosmetics, and pharmaceuticals to attract and retain moisture. In food products, their primary function is to prevent drying out, maintain a moist texture, and extend shelf life by controlling water activity. This control is crucial for preventing microbial growth and maintaining the desired quality of products like baked goods, candies, and dried fruits.
Some common humectants found in food include:
- Glycerin (Glycerol): A sugar alcohol derived from animal fat or vegetable oil.
- Sorbitol and Xylitol: Other sugar alcohols often used as low-calorie sweeteners and to retain moisture.
- Propylene Glycol: A synthetic substance that serves as both a humectant and a solvent.
- Honey: A natural humectant.
- Cellulose Powder (e.g., JELUCEL®): Derived from plant fibers using mechanical processes, positioned as a natural humectant option.
These ingredients are not consumed on their own but are incorporated into products during industrial manufacturing. While some, like honey, can be found in a home kitchen, many are industrially produced and modified for specific functional properties.
The NOVA Classification System and Ultra-Processing
The debate around ultra-processed foods is largely framed by the NOVA food classification system, developed by researchers in Brazil. This system categorizes foods into four groups based on the extent and purpose of their processing:
- Group 1: Unprocessed or minimally processed foods. Foods in their natural state or only slightly altered by processes like washing, freezing, or pasteurization. Examples include fresh fruits, vegetables, nuts, and plain milk.
- Group 2: Processed culinary ingredients. Substances like oils, sugar, and salt that are derived from Group 1 foods but are not meant to be eaten alone. They are used in culinary preparations.
- Group 3: Processed foods. Products made by combining Group 1 and Group 2 foods. These are modified to increase shelf life or enhance taste using methods recognizable in a home kitchen. Examples include canned vegetables, freshly baked bread, and cheese.
- Group 4: Ultra-processed foods (UPFs). Industrial formulations that are typically made from substances derived from foods (like sugar, starches, fats) and contain cosmetic additives not used in home cooking. These products are engineered for hyper-palatability, convenience, and long shelf life.
Humectants as Indicators of Ultra-Processing
The presence of certain humectants is a strong indicator of an ultra-processed product. The NOVA system specifies that additives with cosmetic functions, such as humectants, emulsifiers, and sweeteners, are defining characteristics of Group 4 foods. A key point is that the addition of industrially refined or synthesized ingredients, like propylene glycol or specific sugar polyols, goes beyond standard culinary practices. For instance, a plain yogurt made with milk and cultures is minimally processed (Group 1). However, if that same yogurt has fruit flavoring, colorings, and added humectants or sweeteners to change its texture and taste profile, it becomes ultra-processed (Group 4).
Comparison: Humectant vs. Ultra-Processed Food
| Aspect | Humectant | Ultra-Processed Food |
|---|---|---|
| Definition | A specific substance that attracts and retains moisture. | A classification of industrial food formulations, not a single ingredient. |
| Function | To control water activity, extend shelf life, and maintain texture. | To be convenient, hyper-palatable, and have a long shelf life. |
| Origin | Can be naturally derived (e.g., honey) or industrially synthesized (e.g., propylene glycol). | Made from industrial ingredients (derived substances) and typically contains additives. |
| Consumption | Not consumed alone; a component within a food product. | A finished, ready-to-eat, or ready-to-heat product. |
| Health Implication | Varies by type; some (like excessive glycerol) have been linked to health issues, while others are benign. | Diets high in UPFs are correlated with increased health risks such as obesity, heart disease, and type 2 diabetes. |
| Classification | The presence of certain types is a marker for the UPF category. | The highest level of food processing under the NOVA system. |
The Complexity of Identifying Ultra-Processing
It is important to recognize the nuances in classifying foods. Not all foods containing humectants are equally detrimental. For example, some wholemeal sliced bread is considered ultra-processed due to added emulsifiers and fiber, though it is often considered a healthier choice than other UPFs. Conversely, a food can be ultra-processed without a humectant if it contains other industrial additives and meets the criteria. The issue is less about the single ingredient and more about the overall manufacturing process and formulation. The combination of industrial processing, refined ingredients, and cosmetic additives is the core of the UPF classification.
The use of humectants is part of a larger industrial process designed for efficiency and profit. The end result is a food product with a long list of ingredients—many unfamiliar to the home cook—that often has high levels of fat, sugar, and salt. Learning to read ingredient labels and recognizing these industrial markers is the most effective way to identify ultra-processed foods.
Conclusion
In short, humectant is not ultra-processed itself, but rather an ingredient that is a key indicator of a food's ultra-processed status under the NOVA classification system. Its presence signals a level of industrial formulation not replicated in home cooking. While naturally derived humectants exist, many are synthesized and combined with other additives to create hyper-palatable, long-lasting convenience foods. The concern lies not with a single ingredient but with the overall package of industrial processing, refined ingredients, and cosmetic additives that define ultra-processed foods. For consumers, understanding this distinction empowers better food choices and a clearer perspective on what's in their food.
How to spot humectants on food labels
- Look for polyols: Scan the ingredient list for terms like glycerol (E422), sorbitol (E420), or xylitol (E967).
- Check for glycols: Search for propylene glycol (E1520) or hexylene glycol.
- Recognize other names: Common humectants include polydextrose (E1200), sodium lactate, and sometimes honey.
- Consult the NOVA system: Familiarize yourself with the NOVA food classification system to recognize how specific additives push a food into the ultra-processed category.
- Check for long ingredient lists: A long list of unfamiliar ingredients is a major red flag for ultra-processed foods, often containing multiple additives, including humectants.
For further information on the specifics of the NOVA classification and health impacts, the World Health Organization offers resources.
