The British “Daily Mail” report pointed out that a new study shows that if people choose cheap tea bags in the supermarket instead of traditional craft tea for the sake of convenience, it may cause long-term health problems. The study found that tea bags sold in the famous Tesco supermarkets, Asda supermarkets and Sunbury supermarkets in the UK will cause the daily intake of fluoride by the drinkers, which will lead to high risks of bone and dental diseases.
The researchers collected 38 tea products and tested their fluoride levels. The data were obtained by the University of Derby doctoral students Laura Chan and Alahanna Mehra (Prof. Aradhana Mehra) and Prof. Paul Lynch. They use ion-selective electrodes for analysis, which analyzes trace elements such as fluoride in liquids. The scientists analyzed the dry tea and the tea brewed with boiling water for two minutes, and calculated the fluoride intake of 4 cups of tea a day or 1 liter of tea a day.
The researchers found that supermarket tea bags, whether black tea or green tea, are significantly different from the fluoride content of professional tea brand products. Among them, cheap formulated green tea has the highest fluoride content, averaging 6 mg / liter. Professional tea, the fluoride content is the lowest level, an average of 0.7 mg / liter.
However, according to relevant international guidelines, the daily intake of fluoride by adults should not exceed 3-4 mg. Therefore, the fluoride content of a large number of economical tea bags has reached 75% to 120% of the daily intake limit.
Excessive fluoride intake can cause a lot of health problems. Moreover, in the daily diet, not only tea may contain fluoride, but also seafood, toothpaste, and even some areas of the country have fluoride in drinking water, and some processed foods may also be treated with fluoride-containing water.
The lowest damage to excessive fluoride intake may be the appearance of dental fluorosis, which is the appearance of white and brown spots on the enamel, and finally the teeth become mottled and very ugly. This may be the first sign that fluoride is poisoning the body.
A slightly more serious condition is skeletal fluorosis, a disease that can have serious consequences, including bone and joint pain, muscle weakness, and gastrointestinal problems. People with an average daily intake of 10 to 20 mg of fluoride for 10 to 20 years, or 2.5 to 5 mg of fluoride per day for 40 years. The spine of most critically ill patients will become completely stiff.
Excessive intake of fluoride can also cause osteoporosis. In addition, in areas where drinking water contains excessive fluoride, people are more likely to develop kidney stones. Researchers even believe that excessive bone exposure to fluoride can cause bone cancer in young people. As early as 1992, a study found that in areas with excessive fluoride in drinking water, the incidence of osteosarcoma was three to seven times higher than in normal areas.
Dr. Chen said: “Tea trees and wild tea trees are fluoride ‘batteries’, especially the accumulation of most of the fluoride in the leaves. When the tea is collected, the old leaves are usually used to produce low-quality tea products, like It is a cheap tea bag; the new leaves of the shoots and branches are used in high-quality or characteristic tea products. Although fluoride is considered to be a basic trace element essential for human health, it can prevent tooth decay and promote healthy bone growth, but in daily diet. Excess fluoride can cause damage. Dental fluorosis, skeletal fluorosis, bone and joint pain, and calcification damage can occur. People may be drinking too much fluoride, and they also consume other fluorides every day through diet. The food of the compound is not clear about the harm. In the United Kingdom and the United States, the same situation occurs. People who drink too much cheap tea bags have a higher incidence of skeletal fluorosis than ordinary people. All tea products can be considered It is the main source of fluoride in the diet. We should urge supermarkets and manufacturers to indicate the fluoride concentration in the nutrition information label of the outer packaging.”
Therefore, experts have called for supermarkets and tea producers to consider adding labels such as fluoride concentrations to their outer packaging as part of the disclosure of nutritional information.