As a family physician with many years of clinical experience, I often encounter health problems caused by poor diet. Today, I would like to share an important topic about formaldehyde intake and food safety. Formaldehyde, a colorless chemical, is not only widely used in industry, but it may actually be lurking in the food we consume every day, especially some processed foods. Long-term intake of foods with excessive formaldehyde levels can lead to serious health problems, including cancer. Last summer, a middle-aged lady came to my clinic with persistent indigestion and weight loss. After detailed questioning, I learned that she had a habit of eating pickled seafood bought in the market frequently. Initial examination revealed no obvious organic lesions, and I recommended that she undergo a series of blood and urine tests. The results showed that her formaldehyde intake was much higher than normal, which was a very dangerous sign. This is not an isolated case, in fact, many people who love seafood and preserved foods may unknowingly ingest high amounts of formaldehyde. This substance is formed during improper storage or processing, especially when using prohibited preservatives or when food is handled in an environment that is not properly controlled. Through the course of this patient's treatment, we delved into the dangers of formaldehyde and how to reduce intake through dietary choices and food handling. Not only did this improve her symptoms, but it also made her re-examine her eating habits and adopt safer food choices and handling methods.
Formaldehyde in food
Common formaldehyde-containing foods seafood: Seafood, especially processed seafood such as dried fish and pickled seafood, is one of the foods with high formaldehyde content. The reason is that formaldehyde is a preservative that prevents the growth of microorganisms and prolongs the shelf life of seafood. For example, formaldehyde may be used in the processing of dried fish to preserve its color and freshness. Although this practice can improve the market competitiveness of products, long-term intake of formaldehyde-containing foods is extremely detrimental to health. Pickled foodPickled foods include pickled vegetables, bacon and other foods that have been treated with salt or spices. Formaldehyde may be formed as a by-product during the curing process, especially when using formaldehyde-containing preservatives or colours. Although the formaldehyde content of this type of food is not as high as that of processed seafood, it is enough to attract our attention.
Expired or improperly stored food: Expired food or food stored in improper conditions, such as exposure to high temperatures and humidity, may naturally produce formaldehyde. This is because under these conditions, the proteins in the food break down to form nitrogenous compounds, which can then be converted into formaldehyde.
Detection and identification methods
Watch the label: When buying processed foods, always look at the ingredient label. While not all foods containing formaldehyde will be clearly labelled, avoid those with unknown preservatives or chemical additives. Smell: Formaldehyde has a strong pungent odor and should be vigilant if you smell a pungent odor after opening the package. Buy products from reliable sources: Choose reputable brands and reliable suppliers that don't typically use harmful substances like formaldehyde. Use test kits: There are food safety test kits for formaldehyde sold on the market, and through a simple chemical reaction, you can preliminarily determine whether the food contains formaldehyde.
Health effects of formaldehyde
Short-term and long-term effects of formaldehyde, this colorless gas often has a strong pungent odor, not only widely used in industry, but also commonly found in decoration materials and some foods. Its impact on human health is mainly manifested in two aspects: short-term effects and long-term effects. Short-term effects: Short-term exposure to high concentrations of formaldehyde will quickly show its irritation: Respiratory system: Inhalation of formaldehyde can cause sore throat, cough, chest tightness, and in severe cases, it can lead to bronchitis, pneumonia, etc. Skin contact: Formaldehyde has a strong irritating and corrosive effect on the skin, which can cause dermatitis, redness, pain, and even ulcers. Eye contact: It also has strong irritation to the eyes, causing eye pain, tearing, blurred vision, and prolonged exposure may cause serious eye damage. Long-term effects: Long-term exposure to formaldehyde is associated with more severe chronic health effects, especially carcinogenic risk: Carcinogenicity: The International Agency for Research on Cancer classifies formaldehyde as a "known human carcinogen". Long-term inhalation of low-dose formaldehyde gas can increase the risk of nasopharyngeal cancer and leukemia. Immune system effects: Formaldehyde may also affect the body's immune system, leading to a decrease in immunity, which can increase the risk of infections and the probability of developing other chronic diseases.
A brief description of carcinogenic mechanisms
The carcinogenic mechanism of formaldehyde involves its ability to react with proteins and DNA in the human body. Formaldehyde can form DNA adducts, which can cause structural and functional changes in DNA, triggering genetic mutations that can eventually lead to cell cancer. Gene mutations: Genetic mutations caused by formaldehyde exposure are the direct cause of its carcinogenicity. After DNA damage, the repair mechanism of cells may not be able to completely restore the original structure of DNA, resulting in cell dysfunction and increasing the possibility of cancer. Cell signaling pathways: Formaldehyde may also interfere with signaling pathways inside cells, such as affecting cell cycle control and promoting unrestricted cell division, which is also an important biomarker of cancer.
How to reduce formaldehyde intake
Tips for Identifying Labels: When buying seafood, prefer fresh and untreated goods and avoid processed foods that have been added with preservatives or other chemicals. Check product labels and avoid products that contain formaldehyde or other harmful chemicals. Freshness first: Try to choose fresh ingredients for cooking, fresh vegetables and meats are not only nutritious, but also do not contain added formaldehyde. Avoid buying foods that have changed color or smell, as these may indicate that the food has gone bad, and spoiled food has high levels of formaldehyde. Transparent channels: Try to buy food from reputable stores or markets where food is reliably sourced and of guaranteed quality. When purchasing, you can ask the seller for specific information about the food, including the origin, processing method, etc.
Solution:
Cleaning and soaking: Seafood should be fully cleaned after purchase and soaked in water for a period of time, soaking can help release some chemicals such as formaldehyde from food. For especially dry or pickled foods, it is best to soak them in running water for at least 30 minutes after washing. Cooking treatment: Formaldehyde can be broken down at high temperatures, so proper cooking methods (such as boiling, steaming, stewing) can reduce the formaldehyde content in food. Avoid cooking foods that are not suitable for high temperatures (such as certain pickled vegetables), as this may lead to the production of other harmful substances. Reasonable storage: Food should be stored in a dry, ventilated and cool place, and avoid using containers contaminated with chemicals, such as some plastic containers may release harmful substances. For perishable food, it should be eaten as soon as possible or properly refrigerated to prevent the formation of formaldehyde during the spoilage process.
Food safety standards
Understand the regulations: Familiar with the national or regional laws and regulations on food safety, especially the limit standards for harmful substances such as formaldehyde. Use food safety standards to select food products and prioritize products that meet high safety standards. Use resources: Pay attention to safety information and warnings issued by official agencies such as the Food and Drug Administration. Use food safety testing kits, such as formaldehyde testing agents, for preliminary testing of suspected foods. Through the above methods, we can not only effectively reduce formaldehyde intake, but also improve the overall food safety, and provide more protection for the health of ourselves and our families. Proper purchasing decisions and food handling tips are the first step in protecting us from formaldehyde and other harmful substances.