As a part of Asian culture, drinking tea is a common thing to do. Whether it is hot or iced, sweetened or unsweetened; for us Indonesians having a tea during or after meals is a must. There is even a commercial about ready-to-drink tea that emphasizes to drink tea whatever we eat. Drinking tea, surely, has its own unending benefits; such as containing antioxidants, may reduce risk of heart attack and stroke, may help with weight loss, may help protecting the bones, may boost immune system, may help battling cancer. And most of all it is calorie free when unaltered! However, little did we know, drinking tea also has a negative effect. It can decrease the level of our iron absorption. Based on research, consuming tea during meal can reduce up to 50% of iron absorption. What happens when our level of iron absorption decreases? It may increases the chances of iron deficiency. Iron deficiency may lead to anemia, heart problems such as irregular heartbeat, delay of normal infant motor function or mental function, increase risk for small or early preterm babies IQ, affect memory or other mental function in teens. Symptoms of iron deficiency include fatigue, decreased work performance, colder body temperature and increased frequency of illness.
How does it happen? The culprit of this phenomenon actually comes from the polyphenols compound which is found in the tea. When the polyphenols combine with iron, it makes less available for efficient iron absorption. Other compounds which can also reduce the iron absorption are phytic acid (can be found in wholegrains), dietary fiber, soy protein, oxalate (can be found in spinach), and calcium. These compounds, however, only affect the iron absorption which sources of iron contain non-haem. Non-haem (containing Fe3+) is found in plant foods such as cereals, vegetables, legumes, dried fruits. The absorption of non-haem iron is much less stable. It is influenced by an individual’s iron status and several factors in the diet that can either decrease or enhance its absorption. The iron contain haem (containing Fe2+) which is present in the haemaglobin and myoglobin of animals (meat, liver, and other meat products), are not affected by the consumption of tea. The level of haem iron absorption is relatively unaffected by other dietary factors. This is why people are vegetarian and loves to consume tea while eating meals are more likely to have deficiency of iron than people who consumes meat.
So is it bad to consume tea during meals? Well, we can choose to not drink tea and other beverages which can reduce the efficiency of iron absorption (coffee, milk) during meals; mineral water is the best option. But drinking tea during meals is not that bad if we can balance our diet. The negative effect of drinking tea may occur if we drink too much tea or eat unbalanced diet. Our diet should consist not only vegetables (contains non-haem, harder to absorb) but also meats (contains haem iron, easier to absorb). If we can balance them, then there will be no iron deficiency. According to PKBPOM No. 9 Tahun 2016, daily value of iron for adults equals to 22 mg per day, for expecting mothers 34 mg per day and for nursing mothers 33 mg per day. For adults’ iron daily value, it can be fulfilled with consuming either 100 gram of dark chocolate, 150 gram of chicken liver, 500 gram of red meat (beef and lamb), 500 gram of spinach, 500 gram of lentils or a combination of them. We can also opt to drink tea one hour before or one hour after meals to reduce its negative effect. Drinking tea in moderation is also the key. Nowadays, some of the tea drinks are the trends in Indonesia. It is available almost anywhere and even though it is more expensive than other drinks, some of us still choose the tea drinks from the famous stalls even when we do not know the ingredients in it and drink it excessively. There are also several factors that can enhance the absorption of iron. For example we can put citrus into our tea, making it lemon tea. Citrus can help increasing the level absorption of iron due to its compound called citric acid. It counters the negative effect of tea. Other than citrus which contains citric acid, there is also lactic acid which we can found in fermented milk product such as yoghurt and pickled vegetables. Both citric acid and lactic acid have been found to enhance the absorption of non-haem in recent studies. In cases of iron deficiency in Indonesia, our government also made regulation to strive against iron deficiency. The wheat flours made in Indonesia are fortified with iron as an effort to fight iron deficiency. Why wheat flours? It is a part of our staple food! We use wheat flour as not only the main ingredient or complement for many of our food. So do we have to worry about drinking tea while taking meals? In my opinion, we should not worry about that as long as we keep eating balance diet and keep drinking tea in moderation.
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