You might know that tinned vegetables, legumes and beans count as part of your 5 a day. But are you worried about the tins themselves and wondering if there is a risk from canned food? Are the chemicals to be worried about? What about BPA risk? Should you be worried? Here is the information you need to know to answer your question, is canned food safe to eat and how to reduce exposure.
What is 4,4’-dihydroxy-2,2-diphenylpropane (BPA)?
4,4’-dihydroxy-2,2-diphenylpropane (BPA) is an industrial chemical that has been used since the 1960s to harden certain plastics and resins.
Where is BPA found?
BPA can be found in items such as drinks bottles, baby bottles, food storage containers, tableware, the linings of food cans and take away containers.
Is BPA in my food?
BPA can transfer in small quantities into the food or drinks stored in these containers and because it is so widespread, it is found in the urine of most adults.
Does BPA pose a risk to health?
There has been a growing call to stop manufacturing plastics with BPA and to use alternatives that are potentially less hazardous. BPA is very widespread and this makes research difficult, because it is difficult finding people who have not been exposed. For good reasons it’s also not possible to research a potentially harmful chemical on pregnant women to see the effects on their children. Instead much of the research has been based on animals, and the downside of this, is that not all animal research translates into humans as our bodies are not the same. Animal research has connected BPA exposure to a range of health problems in mice and rats, including fertility issues, asthma, metabolic disorders and obesity. In humans there is concern that BPA may mimic hormones and interfere with their function, including increased risk of obesity, cancer, heart disease and birth defects (1).
The United States National Institute of Environmental Health Sciences (NIEHS), the National Toxicology Program (NTP) and the Food and Drug Administration (FDA) established the Consortium Linking Academic and Regulatory Insights on BPA Toxicity (CLARITY-BPA) to assess the risk posed by BPA. In 2019 they published a report stating they found a significant body of evidence that documents adverse effects of BPA at doses relevant to human exposures and emphasizes the need for updated risk assessment analysis (2). The European Food Safety previous statement was that dietary exposure to BPA is “not a health concern for any age group”, but they have yet to update their position post the Clarity-BPA report.
Alternatives to BPA
While many products are now marketed as BPA free and people are calling for this to be more widespread, there are also concerns over the potential safety of analogues of BPA (BPS or BPF) used as replacements (3).
Do Most of the Cans in the UK Contain BPA?
The Can Manufacturers Institute, an industry trade group, has reported that 90% of food cans are now BPA-free, and that BPS or BPF (BPA analogues – similar to BPA) are not used as replacements. New liners are made of acrylic, polyester, non-BPA epoxies or olefin polymers. Hopefully these will have an improved safety profile, but more research is needed.
Is Canned Food as Nutritious as Fresh Food?
The heating process used during canning, means that just like cooking your food at home, some of the nutrients will be destroyed. Some vitamins and minerals are more heat sensitive than others, and so canned and cooked food is more likely to have less vitamin C and thiamine. Whether this would have an impact on your health, depends on your overall diet, and if you get enough vitamin C and thiamine from other sources. There is limited evidence to know whether canned or frozen foods are more nutritious.
Summary – is canned food safe to eat and how to reduce exposure
I think that part of this comes down to moderation and that if you only eat canned food or takeaways in plastic containers then your risk of exposure is much higher. Instead if you eat mostly whole foods that are not stored in plastic containers you will reduce your exposure. Avoid putting plastics in the microwave or dishwasher, because the heat may break them down over time, and further increase the likelihood of BPA leaching into food. Instead use porcelain, stainless steal or glass for hot foods and liquids instead of plastic containers where possible. Remember that most canned food in the UK does not contain BPA or analogues of BPA. There is also emerging evidence that antioxidants can reduce the impact of BPA (4). Therefore, if your diet otherwise contains lots of fresh fruit and vegetables, the antioxidants in the fruit and vegetables may help to mitigate potential risk from exposure to BPA.
References
1. Wu W, Li M, Liu A, Wu C, Li D, Deng Q, et al. Bisphenol A and the Risk of Obesity a Systematic Review With Meta-Analysis of the Epidemiological Evidence. Dose Response. 2020 Apr;18(2):1559325820916949.
2. Prins GS, Patisaul HB, Belcher SM, Vandenberg LN. CLARITY-BPA academic laboratory studies identify consistent low-dose Bisphenol A effects on multiple organ systems. Basic Clin Pharmacol Toxicol. 2019 Aug;125 Suppl 3(S3):14–31.
3. Thoene M, Dzika E, Gonkowski S, Wojtkiewicz J. Bisphenol S in Food Causes Hormonal and Obesogenic Effects Comparable to or Worse than Bisphenol A: A Literature Review. Nutrients. 2020 Feb 19;12(2):532.
4. Amjad S, Rahman MS, Pang M-G. Role of Antioxidants in Alleviating Bisphenol A Toxicity. Biomolecules. 2020 Jul 25;10(8):1105.
Have you read my other Health Articles such as 7 Tips for Eating for Health, and What are the Health Risks of Microplastics in Food?