When it comes to heavy metals, many people may not be very familiar with them. In fact, heavy metals can also be found in food. Below, the editor will tell you which four foods contain heavy metals; you must be cautious when consuming them.
I. The Harm of Heavy Metals to the Human Body
The human body contains a variety of chemicals, many of which, including proteins, are good ligands for heavy metals. Once heavy metals enter the human body, they will coordinate with important substances in the body, altering their normal physiological functions. They can even enter the nervous system, interfering with its normal function and leading to diseases (such as a persistent vegetative state), or even death.
The process of heavy metal poisoning: ingestion or contact, entry into the body, coordination, transfer, re-coordination, interference with physiological functions, destruction of physiological effects, and a series of chemical processes from a chemical perspective that lead to poisoning.
II. Which Foods Are Likely to Cause Heavy Metal Poisoning
1. Traditional Chinese Medicine
Common ingredients in Traditional Chinese Medicine, realgar and cinnabar, contain arsenic and mercury, respectively. Long-term and large-scale use of realgar and cinnabar can lead to the accumulation of heavy metals like mercury and arsenic in the body, causing severe damage to the liver and kidneys, and potentially harming the blood and nervous systems. Therefore, they must be used with caution.
2. Seafood
Due to the spread of pollution, shellfish and saltwater fish have become the largest sources of heavy metals like mercury and arsenic. Long-term consumption of seafood can lead to the accumulation of toxic substances like heavy metals in the body, harming health.
3. Preserved Eggs (Pidan)
In the production of preserved eggs, a substance called "litharge" is used in the coating material for fresh eggs. Its chemical component is lead monoxide. Adding lead monoxide can promote the even and rapid penetration of the ingredients into the egg and also cause the egg to set quickly, making it easy to peel. However, during the storage process, this lead monoxide gradually seeps into the egg. There are lead-containing and lead-free preserved eggs on the market; you can check the labels to choose lead-free ones. When eating preserved eggs, add some vinegar, as acidic substances can minimize the absorption of toxic substances in the human body.
Additionally, from a nutritional perspective, the nutritional content of preserved eggs is similar to that of regular eggs, except for a higher iron content. However, vitamin B groups and essential amino acids are destroyed during the pickling process. When eating preserved eggs, adding aged vinegar can kill bacteria and neutralize some of the alkalinity of the egg, making it tastier. It should be noted that preserved eggs contain lead, although in trace amounts, children and patients with cardiovascular, liver, or kidney diseases should still consume them in moderation.
4. Animal Offal
Although animal offal has unique nutritional value, it is also a site for heavy metal deposition. Livestock are often fed industrial feed, which can be uncertain. If unsafe food, such as feed or water contaminated with heavy metals like cadmium, is consumed by the animals, their offal is responsible for metabolizing it. Some harmful substances like heavy metals will then deposit in the offal, such as cadmium and lead. These heavy metals remaining in the offal will be transferred to you, endangering your health.
Small Tips:
1. For mild heavy metal poisoning, immediately consume yogurt and seek medical attention promptly.
2. For jobs involving contact with heavy metals, appropriate protective measures must be taken, and regular health check-ups are necessary.