Spoiled food can cause vomiting and diarrhea, and the culprit is mold

Reviewer: Zhang Shuyuan, Chief Physician, Beijing Huayi Integrated Traditional Chinese and Western Medicine Dermatology Hospital

In the hot summer, some people occasionally experience symptoms such as abdominal pain, diarrhea, and vomiting. This may be food poisoning caused by eating food contaminated by mold.

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What is mold?

Mold is the common name for filamentous fungi, which can be understood as "moldy fungi".

Mold easily grows in humid and warm places, especially on nutrient-rich items. Those fluffy, floc-like or spider-web-like colonies visible to the naked eye are mold.

The basic unit of mold is hyphae, which are long tubes with a width of 2 to 10 μm. The hyphae can continue to grow from the front end and send out branches. A large number of hyphae interweave into fluff, flocculent or net-like shapes, which are called mycelium. Mycelium is often white, brown, gray, black or bright colors, such as green Penicillium and yellow Aspergillus flavus. Molds reproduce rapidly, often causing a large amount of food to spoil.

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However, there are also some beneficial species of molds that have been widely used. They are the earliest type of microorganisms used and recognized by human practical activities [1].

What are the dangers of mold?

When talking about the harm of mold, we have to talk about mold toxins, which are toxic metabolites produced by mold in contaminated food. Mold toxins can enter the body through feed or food, causing acute or chronic poisoning in humans or animals, mainly causing damage to the liver, kidneys, nervous tissue, hematopoietic tissue, skin tissue, etc. At the same time, some types of mold, such as Aspergillus flavus, are also carcinogenic and teratogenic.

1. Harm of mold to the liver and kidneys

Aflatoxin is the most toxic fungal toxin known so far. Aflatoxin poisoning mainly damages the liver and can also cause kidney damage. In acute poisoning, patients mainly show acute liver damage; in chronic poisoning, patients gradually develop liver fibrosis, cirrhosis, and even liver cancer.

In our daily life, moldy peanuts, melon seeds, and nuts are likely to contain aflatoxin, so you must be cautious when eating them.

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2. The harm of mold to nerves

Mold toxins can also affect cell growth, causing oxidative stress by increasing the content of active oxygen in cells and damaging cell DNA.

For example, mold toxins can affect brain development and nerve cell growth, and their effects are likely closely related to oxidative stress, DNA damage, and mitochondrial dysfunction. Oxidative stress can lead to mitochondrial dysfunction and DNA damage, and DNA damage is considered to be the main factor that damages the brain region. When mold toxins invade the brain, they damage the hippocampus, causing memory and learning disorders.

3. Harm of mold to skin

Mold is fungus. There are many skin diseases caused by fungal infection. For example, if we stay in an air-conditioned room for a long time, too much mold will accumulate on the air-conditioning radiator, causing skin allergies.

Another example is the common ringworm, which is an infectious skin disease caused by fungi. Due to lack of attention to hygiene in life, external fungi invade the skin, causing infection, and contact can also lead to infection.

How to prevent harmful mold?

Mold is everywhere in our lives. It likes to grow in warm and humid places. When it encounters a suitable environment, it will multiply in large numbers and produce flying spores. When it falls on rice, steamed buns, fruits and vegetables, it will grow hair. So, what measures should be taken to prevent mold from invading our daily lives?

1. Traditional method of mildew prevention

Putting 1kg of kelp in 100kg of rice can effectively kill pests and inhibit mold. But if you find that the food has gone moldy, you must throw it away. Don't eat it for fear of waste. If you get food poisoning, it will not be worth it.

2. Sealed and preserved to prevent mildew

Most molds are aerobic microorganisms that need oxygen to grow and reproduce, so bottled food can be filled with nitrogen or carbon dioxide after sterilization, and deoxidizers can be added at the same time. In this way, the food is deoxygenated, creating an oxygen-deficient environment that can prevent most molds from growing.

3. Low temperature mildew prevention

For example, meat products can be stored at 0℃ for 20 days without deterioration; rice cakes can be completely immersed in a porcelain jar filled with water, with the water temperature kept below 10℃, which can also prevent mold.

4. Heat sterilization and mildew prevention

Most molds are afraid of high temperatures, and can be killed by heating to 80°C for 20 minutes. However, aflatoxin is special and is resistant to high temperatures, and pasteurization (80°C) cannot destroy its toxicity.

Mold is a type of fungus and a microorganism that is widely present in nature and has a great impact on human life.

For the human body, the effect of mold is two-sided: it is a normal colonizing bacteria in our body and is widely present on the skin surface. When the human body's immunity is relatively high, it will not only not cause harm to the body, but also maintain the body's acid-base balance and bacterial balance; but when human immunity is reduced, mold will cause a series of clinical symptoms, causing patients to develop corresponding serious diseases.

Therefore, we must not only improve our own immunity, but also pay more attention to hygiene, including food hygiene, personal hygiene, environmental hygiene, etc., to reduce the damage caused by mold.

References

Wang Yonglian, Liu Xia. Harms and prevention methods of common mycotoxins. Journal of Agricultural Knowledge, 2020 (11): 32-35.