Food additives and preservatives: what they are, what they are used for, and which ones to watch out for

Melanie Ramos 8 min. of reading Legislation and Quality Leave a comment

You’ve probably heard that food additives and preservatives “are bad for you”, but it’s common to have only a vague idea of what they actually are, what they’re used for and which foods contain them.

In this article, we’ll take a look at what a food additive is, how additives are regulated in the European Union and what current scientific evidence says about those that raise the most concerns.

What is a food additive?

A food additive is a substance intentionally added to a food to preserve its properties, improve its flavour or texture, or maintain its appearance. The simplest ones have been used for centuries: salt, vinegar and spices are, in a broad sense, natural additives.

From the second half of the 20th century onwards, the food industry began using more sophisticated synthetic additives — colourings, artificial sweeteners and a wide range of preservatives — to meet the demand for a greater variety of products with a longer shelf life.

How are additives identified?

In the European Union, all authorised additives are identified by the letter “E” followed by a number, in accordance with Regulation (EC) No 1333/2008. An additive having an “E” number does not mean that it is harmful: quite the opposite, it means that it has undergone a safety assessment by the EFSA (European Food Safety Authority) and is authorised within specific conditions and limits of use.

Learn how to correctly interpret the nutritional information on food labels.

Main families of “E” additives

E-100 to E-199: colourings.
E-200 to E-299: preservatives (prevent the growth of bacteria, moulds and yeasts).
E-300 to E-399: antioxidants and acidity regulators.
E-400 to E-499: thickeners, stabilisers and emulsifiers.
E-900 onwards: sweeteners and other miscellaneous additives (glazing agents, packaging gases, etc.).

What is a preservative?

A preservative is a specific type of additive whose purpose is to prevent food from deteriorating: mould growth, oxidation or loss of flavour. Other additives, although not strictly considered preservatives, perform similar functions:

Humectants: prevent food from drying out.
Glazing agents: give foods a shiny finish.
Colour retention agents: help maintain the original colour.
Emulsifiers: prevent phases such as water and oil from separating (mayonnaise, ice cream, homogenised milk).

Natural ways to preserve food

If you prefer to reduce the use of synthetic additives in your cooking, there are traditional techniques that can be just as effective:

Vacuum packing: limits the oxygen available to bacteria, extending shelf life for weeks or months when refrigerated.
Brining: salting is one of the most effective preservation techniques for meats and prepared foods.
Fermentation: used in oils and beverages kept under controlled conditions; as well as preserving food, it can enhance flavour.
Freezing: the most widely used preservation technique at home.
Dehydration: removing water from food, particularly effective for fruit and vegetables.
Pickling with vinegar.
Water-bath sterilisation: food is placed in a hermetically sealed glass jar, the jar is boiled and then left to cool inside the pot; this can preserve food for several months.
Preserving herbs and spices: rosemary, sage, oregano, cinnamon, cloves, ginger and garlic have natural antimicrobial properties.

Are food additives and preservatives dangerous?

This is where the most important nuance comes in: the dose makes the poison. Additives authorised by the EFSA are assessed by establishing an Acceptable Daily Intake (ADI), an amount that can be consumed every day over a lifetime without appreciable health risk.

The real issue is not usually the additive itself, but the overall dietary pattern: the widespread consumption of ultra-processed foods since the mid-20th century has greatly increased our combined exposure to dozens of different additives, a scenario that science is still working to fully characterise.

That said, there is a group of additives that generate greater scientific or regulatory debate and are worth knowing about.

Additives that generate the most debate

Sulphites (E-220 to E-228): They can trigger allergic reactions or asthma attacks in sensitive individuals, particularly people with asthma. This is why legislation (EU Regulation 1169/2011) requires them to be declared on food labels when levels exceed 10 mg/kg. If you’re one of these people, always check the ingredients list on wines, nuts and dried fruit.
Monosodium glutamate (MSG, E-621): For decades, it was blamed for the so-called “Chinese restaurant syndrome” (headaches, nausea). Controlled studies have not confirmed a clear causal relationship at normal intake levels, and both the EFSA and FDA consider it safe within established limits. Some people report individual sensitivity, but there is no evidence of a widespread effect.
Partially hydrogenated fats (trans fats): Unlike the additives above, the evidence here is strong: consumption of industrial trans fats is consistently associated with an increased risk of cardiovascular disease. The EU has limited their presence to a maximum of 2% of total fat content since 2021 (EU Regulation 2019/649).
Artificial sweeteners (aspartame E-951, cyclamate E-952, saccharin E-954, acesulfame K E-950): In July 2023, the IARC (the WHO agency specialising in cancer research) reclassified **aspartame as “possibly carcinogenic” (Group 2B)**, the same category that includes, for example, traditionally pickled vegetables. The JECFA, the committee that assesses the actual risk associated with exposure, kept the acceptable daily intake unchanged (40 mg/kg of body weight), as it found insufficient evidence of risk at usual consumption levels. In practice, a 70 kg adult would have to drink more than 9-14 cans of a *diet* soft drink per day to exceed this limit.
Potassium bromate (E-924): It was used to increase the volume of bread and baked goods. **It is not authorised as a food additive in the European Union**; its use is permitted in the United States and Japan, where it has generated controversy due to studies showing carcinogenic effects in animals at high doses.
High-fructose corn syrup (HFCS): A 2010 Princeton University study in rats linked it to greater weight gain. Subsequent evidence in humans is more nuanced: the issue appears to be related more to the overall excess calorie intake associated with diets high in added sugars than to an effect exclusive to HFCS compared with other sugars.
Sodium benzoate (E-211): When combined with ascorbic acid (vitamin C) under certain conditions (heat, light, prolonged storage), it can form traces of benzene, a compound classified as carcinogenic. For this reason, several beverage manufacturers have reformulated their products to avoid this combination. Health authorities monitor benzene levels in food and beverages to ensure they remain well below risk thresholds.
Nitrites and nitrates (E-249 to E-252): They are used in cured meats and processed meat products to inhibit Clostridium botulinum and maintain colour. The IARC classifies processed meat as a Group 1 carcinogen, partly due to the formation of nitrosamines derived from nitrites during processing or high-temperature cooking. This is one of the reasons why nutrition guidelines recommend moderating the consumption of cured and processed meats.
Olestra: A fat substitute that is now rarely found on the European market; it has been associated with gastrointestinal discomfort and reduced absorption of fat-soluble vitamins.
BHA and BHT (E-320 and E-321): Antioxidants that prevent fats from becoming rancid. BHA is classified by the IARC as possibly carcinogenic to humans (Group 2B); both are authorised in the EU within strict limits, although some sensitive individuals may experience skin or respiratory reactions.
Propyl gallate (E-310): It is used together with BHA/BHT to preserve fats and oils. There is no conclusive evidence of carcinogenicity in humans, although some animal studies suggest that continued monitoring is warranted.
Titanium dioxide (E-171): This white colouring, once widely used in sweets, chewing gum and some food supplements, **has been banned as a food additive in the European Union since 2022**, following an EFSA assessment that could not rule out concerns regarding genotoxicity. It is one of the most recent examples of how European regulation responds when reasonable scientific concerns arise, even in the absence of definitive proof of harm.

The “good” additives: antioxidants considered safe for use

Not all additives generate controversy; many are synthetic or natural forms of nutrients already present in the diet:

E-300 (ascorbic acid / vitamin C): improves the properties of flour; widely used in bread-making.
E-306 (tocopherol / natural vitamin E): antioxidant of natural origin.
E-308 (synthetic tocopherol): performs the same function as E-306 and is commonly found in weight-management products.
E-325 (sodium lactate) and E-326 (potassium lactate): acidity regulators derived from lactic acid, with no known adverse effects at authorised doses.

How to reduce your exposure to additives without becoming obsessed

You don’t need to completely eliminate packaged foods to maintain a healthy diet. Here are some sensible guidelines:

Prioritise fresh fruit and vegetables, whole grains, eggs, and fresh meat and dairy products.
Check food labels when buying packaged products: generally, the fewer unfamiliar ingredients, the better.
If you have allergies, asthma or a known sensitivity to a particular additive (sulphites, colourings such as tartrazine E-102 or carmine E-120), pay particular attention to the ingredients list.
Moderate your consumption of ultra-processed foods and cured meats rather than trying to eliminate one specific additive in isolation.

*This article is for informational purposes only and is not a substitute for advice from a healthcare professional, particularly if you have allergies, intolerances or pre-existing medical conditions.

Sources

For further information on current legislation: https://ec.europa.eu/food/safety/food_improvement_agents/additives_en

Related Posts