Added chemicals enhance flavours, colours, textures, and ensure the safe preservation of every day products, such as food and medicine. In Australia, over 300 industrial chemical additives have been assessed for their safety and approved by Food Safety Australia and New Zealand, and the Therapeutic Goods Administration. Nonetheless, consumers and researchers are increasingly concerned over growing reports on the negative health effects of commonly used additives.
Researchers with more precise methods are unveiling adverse effects of approved additives.
Industrial chemicals added to consumer products are synthesised using chemical processes. These additives may be chemically identical to naturally occurring compounds, such as salicylic acid and benzoic acid, found in many fruits and vegetables. Some are derived from natural materials, such as preservative rosemary extract, whitening agent titanium dioxide from the mineral illmenite, and dietary emulsifier carrageenan from red seaweed. As the consumer demand for safe and natural products increases, food and therapeutic goods industries are marketing “natural” alternatives to traditional additives. Nonetheless, almost all industrial chemicals absorbed by our bodies are considered xenobiotic — as the higher concentrations found in ultra processed products are not naturally encountered by the body. For this reason, most chemicals added to consumer products require toxicity testing.
Xenobiotic metabolism is a body process that transforms foreign matter enough to be excreted. However, xenobiotic metabolism is tremendously variable, and poses complex consequences. Depending for example on whether the necessary enzymes or gene expression is affected, its effects on microbiota composition, or whether the resulting metabolite is toxicologically active or not. In pathology, xenobiotics induce cell and tissue damage, known as oxidative stress.
Researchers recommend limiting exposure to additives.
Oxidative stress is primarily caused by an imbalance between pro-oxidants and anti-oxidants. Persistent and prolonged oxidative stress is known to exert chronic, low-grade inflammation. The medical community has long recognised chronic inflammation to be at the root of over 100 human diseases. Chronic inflammation has been associated with anxiety, hyperactivity and inattention, decreased motivation, chronic fatigue syndrome, irritable bowel syndrome, autoimmune diseases, fatty liver disease, and more.
Safety authorities approve of this practice by evidencing the low acute, sub-chronic, and chronic toxicity of individual additives at higher doses than that allowed in the consumer market. Safety authorities in reviewing more recent research have stated that adverse effects at lower doses may only be an issue for sensitised people. For example, the European Food Safety Authority in 2016, noted that benzoic acid may increase hypersensitivity. They also observed that doses below the Acceptable Daily Intake induced anaphylaxis and urticaria in sensitive individuals.
On the other hand, increasing numbers of researchers with more precise methods are unveiling adverse effects of approved additives, even at low doses, in the general population and in animal models. In many of the past and recent studies, the negative health effects of additives increased in a dose-dependent and time-dependent manner. Furthermore, current toxicological studies are limited by their focus on individual additives. Modern humans consume a variety of additives daily, in a wide-range of products including food, dietary supplements, medicines and personal-care items — thereby significantly increasing the level of exposure. The damage that many such additives alone or in combination yield isn’t well known.
In the absence of further studies, researchers recommend limiting exposure to additives, in particular ultra-processed foods. This is especially important for those with chronic health conditions, and other vulnerable people such as children and the elderly.