Tea and Iron Absorption

I was having dinner with friends last night and the waitress was asking if we would like tea to go with our meal. One of my friends highlighted that his wife read somewhere that it is not good to drink tea with meal as it reduces the iron intake from our meal. I found it quite interesting and when I woke up this morning, I googled to see if I can find any information regarding this.

It wasn’t difficult to find information in the internet at all nowadays – as long as you spend some time on it. The search returned several results related and non-related. In all of the related results, they had shown similar information – that tea reduces the iron intake to a certain extent and it really depends. I will come to that in a short while.

Before we go on, let’s take a look at the mineral iron, with the symbol Fe in the periodic table. From my previous knowledge in school, I knew that iron is an essential part in hemoglobin for oxygen transport around the body. According to the British Nutrition Foundation, they stated, “Iron is also required for energy metabolism and is necessary for neurological development of developing embryos. Iron is also needed for the normal function of the immune system.”

Iron can be found in foods in two forms, namely haem and non-haem iron. Haem iron is found mainly in meat, liver, offal and meat products. According to a document by the UK Tea Council, typically 20-30% of haem iron is absorbed from the diet and the level of haem iron absorption is relatively unaffected by other dietary factors.

According to the document, non-haem iron is found in plant foods such as cereals, vegetables, pulses, dried fruit, etc and compared to haem iron it is relatively poorly absorbed, typically less than 10% and often under 5%. The absorption of non-haem iron is much more influenced by an individual’s iron status and several factors in the diet that can either inhibit or enhance its absorption.

Deficiency of iron in our body can ultimately result in anemia while too much of it can be toxic. Moderation is the key. According to the British Nutrition Foundation, iron deficiency anemia can make people feel tired, irritable and less able to concentrate. In children, it can affect behavior and development. Iron deficiency anemia is probably the most common nutritional deficiency in the world - it is estimated that at least 500 million people are affected.

According to the different sources of information that I gotten from Google, all of them stated that tea drinking mainly affects the absorption of non-haem iron as haem iron is relatively unaffected by tea. Most studies which were conducted to examine the effect of tea drinking on absorption of iron concluded that tea does have an inhibiting effect on iron absorption. However, there are people who argued that these studies were carried out in experimental conditions and may not reflect the role of tea when consumed as part of a complex, real diet.

According to the UK Tea Council, their researches also found conflicting results; some have found a higher risk of anemia amongst tea drinkers compared to non tea drinkers, while others have shown no such association, both in children and adults. There is however a lot of other determining factors that can affect the absorption of iron; like what kind of foods were taken beside the tea, the iron status or level of the person in the first place etc.

Practical advice for tea drinking in relation to iron status (Tea and Iron Absorption, UK Tea Council)

• There is no evidence to suggest that tea drinking should be restricted in healthy individuals who are not at risk of iron deficiency and are consuming a well balanced, mixed diet.

• People who have a poor iron status should avoid drinking tea with meals and up to at least one hour after the meal. Any adverse effects that tea may have on iron absorption are then likely to be minimized. This restriction should apply to all people who are in the following at-risk age groups - children less than 6 years of age, adolescent girls, women aged 18–49 years and women aged 75 years and over, as well as those who are known to have poor iron status.

• Moderate tea drinking (3-4 cups) spread throughout other times of the day is unlikely to have any adverse effect on iron status. The inhibitory effect of tea on iron absorption maybe partially overcomes by the simultaneous consumption of animal tissues and Vitamin C.

Something else interesting which I found out is that Vitamin C found in fruits, fruit juices and vegetables actually enhance the absorption of iron. Thus some actually suggest adding lemon to tea to reduce the effect of tea on absorption of iron.

In so speaking, you do not really have to refrain from drinking tea with meal especially if you are having a balanced diet and you are a healthy individual. Only when you are at high risk of iron deficiency, then it would be better to avoid drinking tea with meals. Wishing everyone great health!