Even though Americans are mostly coffee-lovers, tea is becoming more and more popular. But do these two drinks have the same benefits? Nutritionist Anthony Berthou is here to clear things up for us.
Why is it good for us?
Tea is particularly rich in catechins which are very powerful antioxidants from the flavonoid family which help to protect us from numerous diseases (see our article on antioxidants). Of the different types of tea, green tea is the most beneficial because it contains epigallocatechin gallate (EGCG), a very strong and protective antioxidant that is not found in any other plant in such quantities. Other teas are of course still very beneficial for our health.
Thanks to the presence of flavonoids, tea allows the prevention of cardiovascular diseases; these molecules improve blood flow and arterial flexibility. Drinking three cups of green tea per day reduces the risk of cardiovascular disease by 36% (13% for black tea). Flavonoids are also associated with protecting our brains as we age.
Finally, flavonoids help prevent oxidation of LDL cholesterol. We should remember that cholesterol oxidation poses more threats to the body than high cholesterol levels do; oxidized cholesterol contributes to plaque formation between the arteries.
To note: rooibos is an infusion that does not contain theine. This plant contains antioxidants, but in much lower quantities than those found in tea.
Theine or caffeine, it’s the same thing!
Contrary to popular belief, theine and caffeine are the same molecule, and there are no differences between the two. The difference in name is linked simply to historic reasons.
So, just like coffee, tea contains caffeine and helps to stimulate the brain. It likewise has benefits for attention and awareness, fatigue reduction, and even improving memory (see more below).
On average, a cup of tea has 3 to 4 times less caffeine than a cup of coffee does. The content can vary according to the kind of the tea or coffee and according to its infusion method.
On the other hand, though, the theine present in tea is better absorbed by the body. Effectively, the tea tannins slow down the body’s absorption of caffeine. This is why tea stimulates without leading to the type of excitement or jitteriness that coffee can cause for certain people.
Should you avoid tea if you have an iron deficiency?
Tea tannins contribute to a weaker absorption of iron. In fact, when consumed during a meal, tea can prevent 60% to 70% of iron absorption. This is true without much variation for black and green teas.
As such, people with iron deficiencies should avoid drinking tea during meals so that iron-rich foods and tea do not find themselves in the same place at the same time. Wait at least 2/3 hours until consuming tea after eating.
To wrap up, here is some advice for choosing and consuming your tea wisely:
Avoid boiling water
It is best to infuse your tea at 85°C (185°F) to support catechin extraction (temperature is recommended for nutritional reasons rather than for taste preferences).
Choose organic tea
Lots of fungicide and pesticide treatments are used in tea cultivation, which leave traces in the final product. Organic tea, even if it does not totally escape this contamination, allows us to consume a much less polluted tea.
Drink at least two cups of tea per day
In order to feel the strongest benefits, consume at least two mugs of tea per day, ideally 4.
Go for loose leaf tea
Avoid sachets of powdered tea which are much lower quality and which are most affected by pesticide and heavy metal contamination (especially aluminum and fluorine).
Remember to hydrate with water as well
Throughout the day, don’t forget to drink water because tea can have a diuretic effect when consumed in high doses.
Allow your tea to infuse for at least 5 minutes
This infusion time is best because it allows the catechins to be released as much as possible. It can however give the tea a bitter taste.
Why is it good for us?
Just like tea, coffee is great for our health because of its antioxidant richness (especially chlorogenic acid, trigonelline and choline) which contributes to the prevention of many different diseases: liver issues, Parkinson’s and Alzheimer’s disease and even certain cancers (liver, pancreas). According to one American study, consuming at least four coffees per day will reduce the risk of colon cancer relapse amongst patients who already had colon cancer.
Multiple studies have demonstrated that a daily consumption of coffee could help lower risk for diabetes. Effectively, it improves insulin sensitivity, the hormone in charge of regulating blood sugar levels. It will also help to generally reduce liver diseases. However, these results were only observed in heavy coffee drinkers (3 to 4 cups per day).
In fact, coffee is rich in caffeine, a natural substance which stimulates our nervous system, helping to increase focus and concentration and also our physical abilities. Caffeine has a structure similar to adenosine, a compound whose responsibilities are to slow nervous system activity and to regulate our desire to sleep. Caffeine’s structure will bind to adenosine receptors and therefore block or slow down their function. As such, coffee should never be a substitute for true rest.
To note: decaffeinated coffee has the same benefits as those previously mentioned, apart from the stimulating effect. However, it is necessary to choose a product that is labeled “solvent-free.” Effectively, to remove the caffeine, one of the techniques consists of immersing the coffee beans in solvents, which are chemical products that we find traces of in the final product. Alternatively, natural decaffeination methods exist, involving the use of hot water.
Consume with moderation
Long-term consumption of moderate quantities of coffee (2 to 3 cups per daily) seems to be rather beneficial for the cardiovascular system (even though drinking coffee can slightly increase one’s blood pressure in the hours that follow).
However, at heightened concentrations and for people with lots of toxins in their liver (see below), drinking too much coffee can increase one’s blood pressure in the long run and indirectly lead to cardiovascular problems. But, these problems have been observed more when coffee is associated with other risk factors: tobacco, obesity, hypertension, cholesterol, etc.
Caffeine is a xenobiotic substance: it is a molecule that is foreign to the body that the liver must eliminate. In cases of xenobiotic excess (contraceptive pills, tobacco, pesticides, medicines, etc.), the liver can struggle to eliminate them effectively. So, while coffee has beneficial effects on certain liver cells, it can also create problems among others.
Additionally, caffeine consumption stimulates the metabolism. For people with intense fatigue, this can lead to difficulties managing their acid-base balance, leading to an aggravation of this fatigue in the long run.
According to the European Food Safety Authority (EFSA), a safe daily consumption is 200 mg of caffeine per day, which corresponds to about 2 cups of coffee (7oz. cups). Except for pregnant people who should avoid it, consuming up to 400 mg (or 4 cups a day) poses no risk to people with healthy liver function.
To wrap up, here is some advice for choosing and consuming your coffee wisely:
Limit your coffee consumption to 2 cups per day
This recommendation should be adapted to each individual’s ability to process caffeine.
Choose arabica over robusta
Arabica is a variety that is grown at high altitude. It has a better taste and contains less caffeine than robusta does.
Choose a coffee that comes from an equitable source
This ensures the best working conditions for producers and a more respectful relationship with the environment.
Choose an organic coffee or coffee from small responsible farms
This coffee contains fewer pesticides and chemical products than those which come from big farms.
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