Green Tea and Fluoride
Green tea is simply a miracle drink that offers a host of health benefits to those who drink it. However, some worry that green teas simply have too much fluoride and should be avoided. The difficulty in this argument is separating fact from fiction, true science from theories. There is lots of information available on green tea and fluoride, but most of it mangles the facts and mixes in theory or even personal opinion without clarifying the difference.
First, it is important to understand that fluoride can be helpful in low doses. Throughout America fluoride is actually added to your drinking water in order to reduce cavities, especially in children. The Center for Disease Control (CDC) recommends daily intake of fluoride specifically for this reason and says the only danger of too much fluoride is fluorosis or a discoloration of your teeth. However, in 2005 Dr. Michael Whyte raised questions about instant iced tea and skeletal fluorosis based on his analysis of a patient. The patient drank 17 - 33 cups of low quality, instant iced tea a day and Dr. Whyte's analysis attibuted her health problems to the high amount of Fluoride in that tea. Others have suggested that high amounts of fluoride could cause thyroid problems as well.
The daily recommended amount of flouride intake is 3 mg for women and 4 mg for menwith a maximum of 10 mg/day for both. Now let's look at tea and fluoride.
The tea plant, Camellia sinensis, naturally absorbs fluoride from the environment more effectively than other plants. And as it ages, more fluoride is absorbed by the leaves, so the younger leaves have less fluoride than the older leaves. In practical terms, this means white tea (which is only very young leaves) has less fluoride than green, black or oolong teas, which include older leaves (Herbal teas do not contain any Camellia sinensis leaves and have almost no fluoride to speak of). In addition, the younger the leaves make a higher quality tea. Tea dust (in tea bags) and tea bricks (made from older leaves) have much higher levels of fluoride than high quality tea. This study explored the difference between high quality teas and low quality in terms of fluoride: high quality teas had significantly less fluoride (because of the leaves used).
This is part of the issue: in order to understand the amount of fluoride in teas, you need to divide out teas into bottled, bagged, and loose-leaf. Bottled teas have much, much higher amounts of fluoride than bagged, which is higher than loose-leaf. This is partially because of the age of the leaves (bottled are the lowest quality and bagged are the next lowest quality). But also bottled teas are made with fluoridated water that adds significant amounts of fluoride to the tea.
So here's the reality: a cup of loose-leaf green tea generally contains 0.3 to 0.4 mg of fluoride. So it would require 10 cups to hit the recommended daily dose and up to 30 cups to hit the daily maximum. However, this assumes you are only getting fluoride from your green tea, which is not the case. Unless you are filtering your water (or drinking bottled water), not using toothpaste and not taking virtually any medicine, you are receiving fluoride from other sources. In other words, don't max out on fluoride from tea because you are also getting it from other sources.
The reality is that most people drink a few cups a day of green tea at most. And, as we recently noted, most studies recommend around 8-10 cups of tea a day, which should include some white and herbal teas (both have very little fluoride). This would be far below any level that could endanger your health, even if the CDC is wrong about the limited dangers of fluoride.
If you are still concerned, there are a few things you can do to reduce the amount of fluoride in your tea. Here are our recommendations:
- Drink high quality, loose leaf teas. Teavana only offers this type of tea because it tastes better and offers more health benefits in addition to being lower in fluoride. And avoid bottled green teas in particular, which seem to have numerous times the fluoride in loose-leaf green teas (and a lot less antioxidants).
- Drink more white teas. White teas have more antioxidants than green tea, so many of the health benefits are still there, but they have a much lower amount of fluoride. Green tea also has the benefit of EGCG, so don't cut out all of your green tea consumption.
- Use filtered water to make your teas. This has the added benefit of making your tea taste better, but it also filters out the fluoride added to your drinking water, which reduces the amount of fluoride in your tea.
- Drink more Japanese green teas. Because fluoride comes from the environment, soil matters. And for some reason, Japanese green teas (likeSencha, Gyokuro and Matcha) have less fluoride than Chinese green teas.
The argument that green tea is bad because of fluoride seems to have gotten out of control. The reality is that some fluoride helps prevent cavities and strengthen bones. But too much can be harmful. Green tea, however, will not cause problems in this regard unless you are drinking a huge amount daily. In Dr. Whyte's study, the patient was drinking gallons of very low quality tea daily.
It's interesting to note that some of the tea studies related to green tea show that it helps prevent the very diseases that fluoride threatens, such as Alzheimer's. The threat from fluoride could be true, but green tea isn't the culprit putting it into your system. And green tea offers a great deal of positive health benefits from EGCG, antioxidants, etc. that tap water (and its fluoride) don't. It seems silly to throw the baby out with the bathwater in this case.
I hope this helps you to understand the issues involved.
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