Last week I wrote about the main varieties of tea, its nutritional profile and what the research is saying about its health benefits.
This week I want to share my top ten tips to help you enjoy a healthier cuppa!
1. Be choosy about where your tea is grown
The quality of the food we eat is very much dependent on the quality of the environment in which it is grown.
Tea absorbs elements from the soil in which it is grown, and these bioaccumulate in the tealeaves. If the soil contains heavy metals like lead, mercury, lead, aluminium, arsenic, or cadmium, then the tea plants will bioaccumulate those heavy metals in addition to healthy trace minerals like calcium, magnesium, chromium, manganese, iron and zinc.
And unfortunately, much of the world's tea is grown in countries that burn huge amounts of coal for power. Coal-powered energy stations spew lead and mercury into the surrounding environment. Studies have shown that agricultural soils in certain tea-growing countries are polluted with lead, mercury, arsenic and cadmium. While the amounts of these heavy metals that accumulate into the tealeaves we buy may be small, these can bioaccumualte in human tissues over time, and can add up over a lifetime of frequent tea drinking!
I adore tea and refuse to demonise it or contribute to a scare campaign. But by the same token, I’m not going to be an ignorant, blindly-trusting consumer. I wasn’t put here on Earth to make a food or beverage company rich at the expense of my health, dahlinks, and neither were you!
Whilst overseas scientists have tested various teas available for sale, I wasn’t able to find a similar study for teas sold in Australia. So whilst the research is still incomplete, at my place we practice what is known as “the Precautionary Principle”. Basically, we avoid things that have a question mark over them - until the science firms up and shows us they are safe. Studies to date have indicated that the highest levels of lead, arsenic and other heavy metal contamination occur in countries with high levels of pollution, so we are choosing to source our tea from cleaner environments, with minimal exposure to toxicants in ground water, soil, air, and rain.
I encourage you to do your own research on this issue. I have included a list of peer-reviewed studies in the reference list below. At my place we drink Nerada Black Tea and Southern Forest Green Tea.* An added bonus is that these teas have much lower "food miles" than teas grown overseas. Do drop me a line and let me know which brand or variety of tea you choose!
2. Be choosy about how your tea has been grown too
In addition to the environment in which tea is grown, what is applied to the tea while it is growing (rain, irrigation water, pesticides, fungicides) will have an impact on the tea we drink.
Whilst there are small but growing number of investigations into heavy metal contamination in the tea we drink, there is very little data on pesticide residues. I did manage to find a 2014 investigation undertaken by a Canadian news service; they engaged a lab to test a range of black and green teas on sale in Canada, and found that half of the teas tested contained pesticide residues above the allowable limits in Canada. And eight of the 10 brands tested contained multiple chemicals, with one brand containing residues of 22 different pesticides. Click HERE to read more. This is concerning as investigations have shown that pesticide residues in tea leaves will leach out during brewing into the tea we drink.
So as with heavy metal contamination, we practice “the Precautionary Principle” and choose to drink tea from producers who choose to take a careful approach to how they grow their tea. I really encourage you to do your own research - and drop me a line if you find a brand or variety of tea that ticks this box for you!
3. Be mindful of your overall fluoride intake
So we now know that tea plants will absorb minerals and other elements from the soil in which they are grown. And tea is a known "hyper-accumulator" of fluoride. So if there is a lot of fluoride in the soil (from long term use of pesticides and commercial fertilisers) there will be fluoride in the tea you drink.
As the old saying goes, “the dose makes the poison” and that is certainly the case with fluoride. In small amounts, fluoride can actually have a beneficial effect on our dental health. But as with other elements, it can bioaccumulate in our tissues. And it is our cumulative exposure from all sources of fluoride that will determine whether we are exposed to a healthy or harmful amount of fluoride.
Tea is only one of many potential sources of fluoride intake, so you need to consider all potential avenues of exposure. Non-tea sources of fluoride include fluoridated water (used for drinking or agricultural irrigation), beverages made with fluoridated water, agricultural fertilisers, pesticides, certain medications (I was surprised to learn just how many medications contain fluoride - more than 200!), fluoridated toothpaste and mouth washes, beer, wine, cigarettes and even cooking with non-stick Teflon pans.
Excessive tea consumption over long periods (I’m talking 10 years+), could potentially result in musculo-skeletal fluorosis and pain, particularly if the tea is grown with pesticides and/or commercial fertilisers, is consumed with fluoridated water, and especially of you take fluoridated medications. But don’t panic, the reported cases of tea-related fluorosis have involved daily consumption of 1.8 to 3.8 litres of tea over decades.
If you drink a LOT of tea, use fluoridated water and also take a fluoridated medication, and especially if you have arthritic-type bone or joint pain, it may be worth asking your doctor for a blood and/or urine test to determine your serum fluoride levels and decide whether you need to manage your fluoride exposure.
4. Steep your tea for 3 minutes
3 is the magic number when it comes to tea. A 3 minute steeping time has been found to strike the ideal balance, both minimising the leaching of heavy metals into your tea whilst ensuring we can extract as much of tea's healthy polyphenols as possible.
5. Don’t drink it too hot!
Consumption of very hot tea (and other beverages) has been linked to oesophageal cancer. It’s not the tea that is the problem; it’s the super-hot temperature that causes repetitive trauma to the cells that line the oesophagus, which over time can lead to DNA/cell mutations and cancer. The International Agency for Research on Cancer (IARC) has declared regular consumption of very hot beverages over long periods of time is “probably carcinogenic to humans”. You can read more HERE.
It’s very simple to avoid this risk: just let your tea cool to below 65°C (150°F) before you drink it.
6. Consider your iron status
Studies have shown that drinking tea with your meals can reduce iron absorption. This is because the tannins in tea can bind with the iron in our food (particularly non-heme/plant-source iron) and reduce its availability by up to 50%.
So if you are at risk of iron deficiency, wait at least an hour after your meal before pouring a cuppa.
7. Be mindful of what you add to your tea
Water: the quality of water you use to brew your tea will of course impact the quality of the tea you drink.
Sugar: if you choose to add sugar to your tea, be mindful of how much added sugar you are consuming throughout the day (it can all add up over the course of the day!), and consider cutting it down or cutting it out altogether. You can read more about sugar HERE.
Milk: There have been some questions around whether adding milk to tea binds to its polyphenols and reduces their absorbtion, however most studies indicate that milk has either a neutral or positive impact on polyphenol absorbtion. So there is no need to avoid adding milk, unless you don't like it, or have an allergy or intolerance.
Lemon: adding lemon to your tea will give it a flavour and Vitamin C boost. This can be especially helpful if you are at risk of iron deficiency and wish to enjoy a cup of tea soon after your meal, as Vitamin C can boost absorbtion of non-heme iron. Adding lemon also lowers the pH, which can enhance both the release, and your absorption, of tea's polyphenols.
8. Steer clear of supplements and extracts
The supplement industry has capitalised on the reductionist thinking that has pervaded nutrition science, producing isolated supplements including ECGC and L-theanine. Appropriate dosing and long-term safety of these compounds are unknown. At best, the studies don’t support the marketing hype. At worst, lives have been endangered.
The composition of these substances has been found to vary wildly. Some supplements have been found to contain D-theanine, a slightly different form that may not have L-theanine’s health benefits. Green tea supplements have been found to interfere with some medications and have also been associated with liver damage.
To get the heath benefits of tea, just DRINK TEA, in reasonable amounts, steep it for 3 minutes - and stay away from supplements.
9. Enjoy a variety of black/oolong and green/white but don't drink too much!
In Part 1 I detailed the phytonutrients balances in the five main varieties of tea. White, Green and Matcha teas have higher amounts of catechins, whilst oolong and black teas have higher amounts of Theaflavins and Thearubigins. Drinking a variety of teas, will provide you with the benefit of both catechins and theaflavins/thearubigins.
Troubles with tea really only arise where people consume too much of a good thing. So keep your tea consumption to less than 4-6 cups per day, depending on the strength of the brew.
10. Enjoy your tea as part of an overall healthy diet
While tea has a lot of health benefits, on its own its not a “magic bullet”, and too much can be unhealthy. After decades of reductionist thinking, researchers now realise that it is our consistent, overall diet over many years that has the greatest impact on our health.
So enjoy your tea as part of a regular diet that features a rainbow of healthy plant foods, lean protein, healthy fats and whole, unprocessed carbs - and keep my top ten tips in mind when you do!
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* I have no affiliation with Nerada or Southern Forest - or ANY food company for that matter. In fact, I have had no contact or communication with either company at all (except as a paying customer). If you have found a tea producer you like, who ticks all of the above boxes, feel free to drop me a line!