Between the impending summer months and that little wedding across the pond last Saturday, tea has been on my radar.

Hot summer days demand iced tea, and of course, the UK is synonymous with copious tea consumption, but what does any of that have to do with breast cancer?

No doubt you’ve heard that tea (especially GREEN) has breast cancer benefits, and it’s those benefits I want to briefly explore.

You know I write this stuff so you can feel confident making food and drink choices as you move into treatment, right? I translate science into recommendations for action, rather than simply sharing splashy headlines that only leave you confused and frustrated!

Tea consumption is one of those headlines that can lean toward splashy, as in THIS example from an online (completely unreliable) source I stumbled upon:

“Green tea is being hailed as one of the “must use” natural cures for breast cancer. Discover why so many cancer experts say this plant is one of the absolute best breast cancer cures on the planet…”

Sigh.

Honestly, it would be impossible for me to eradicate all of the breast cancer nutrition nonsense in the world, but I CAN continue to share the unvarnished truth, so let’s dive in. . . .

Background

All tea comes from the leaves of the same plant, a warm-weather evergreen named Camellia sinensis. While there are countless varieties of tea, there are only six categories of tea: (1)

  • Black
  • Green
  • Oolong
  • Yellow
  • White
  • Dark

The differences among these six categories are the result of various degrees of processing and the level of oxidation. Black tea is fully oxidized, oolong tea is partially oxidized, green, yellow and white tea are not oxidized, and dark teas are fermented.

After water, tea is the most widely consumed beverage in the world. In 2017, Americans consumed 3.8 billion gallons of tea; 86% black, 13% green, and the small remaining amount a combination of oolong, white and dark (yellow tea is extremely rare.)

Approximately 80% of the tea consumed in America is iced (or the American English version. . . “ice” tea), and did you know that tea is nearly 5,000 years old, purportedly discovered in 2737 BC by a Chinese emperor? (2)

What About Herbal Tea?

Herbal tea is NOT tea. Remember, all categories and varieties of tea come from the leaves of the Camellia sinensis plant. Herbal “teas” don’t contain tea leaves, they’re made from herbs like peppermint or chamomile, and the roots, leaves, seeds or flowers of other plants.

Herbal “teas” still contain health-supportive compounds like antioxidants, so it’s fine to include them in your diet, but they don’t convey the identical health properties of tea because they aren’t, well, tea!

Tea and Breast Cancer

A variety of compounds and nutrients have been identified in tea.

  • Caffeine
  • Catechins
    • Epigallocatechin gallate (EGCG) (dominates in green tea)
    • Epicatechin, epigallocatechin (EGC), epicatechin-3-gallate (ECG)
  • Polyphenols
    • Theaflavins & thearubigins (black tea)
    • Theasinensins (oolong tea)
  • Flavonols
    • Quercetin
    • Kaempferol
    • Myricetin
  • Amino acid L-theanine
  • Manganese and flouride

There are literally thousands of research studies (animal, cell, and human) on tea and breast cancer risk; I had more than 20,000 results from a Google Scholar search alone. You could cherry pick studies to support any one of the above compounds and nutrients as being beneficial in reducing breast cancer risk.

Many individual studies do share interesting findings, such as a 2017 study looking at how tea may have the ability to modify DNA without changing its overall structure to positively affect estradiol (a type of estrogen) metabolism. (4)

However, when we look at the scientific literature COLLECTIVELY, for both premenopausal and postmenopausal breast cancer, there is limited evidence, in terms of amount, consistency and quality to draw strong conclusions about whether tea consumption increases or decreases breast cancer risk reduction and/or prevention. (5)

What Does That Mean For ME?

It means that if you enjoy tea, continue to drink it!

Unproven doesn’t mean disproven, and tea research is ongoing. According to the American Institute of Cancer Research (AICR). . .

“Small human studies show that drinking tea can temporarily raise our cells’ ability to have antioxidant activity, a term known as antioxidant capacity. Antioxidants can stop the possible damaging effects of unstable molecules called free radicals. A balance of antioxidants and free radicals is necessary for good health, but it is unknown what levels of antioxidants protect against cancer.”

Tea has been used medicinally for centuries, so including it in your diet isn’t harmful. But remember, when I share with you about the power of foods and beverages in relation to breast cancer, I use folklore and anecdotal information as points of interest, and the most current research to frame my professional nutrition guidance.

Take-away Actions From Today:

  • Include all of the different tea categories in your tea line-up.
    • You’ll “drink” in the collection of benefits found in all varieties.
  • Choose unsweetened bottled tea (read the label carefully.)
    • Added sugar = added calories. Aim to not “drink” your calories if you can avoid it.
  • To get the highest antioxidant levels, choose HOME-BREWED over bottled tea.
    • A study measuring the level of phytochemicals in six brands of bottled tea revealed that half of them contained virtually no antioxidants, and the rest had such a low level that they would probably carry very little health benefits. (6)
  • Enjoy milk in your tea but concerned it decreases antioxidant levels? Continue!
    • Research shows both outcomes, that milk does and doesn’t impact antioxidant levels (I know, frustrating, but that’s research!)
    • The amount of antioxidants depends on many factors: tea brand and category, whether milk is skim, whole, or plant-based, whether or not sweetener (and what TYPE) is added. (7, 8, 9)
  • Hot or cold? Choose YOUR preference.
    • There doesn’t appear to be a concrete answer as to which temperature or what amount of steeping time provides the highest level of antioxidants.
    • Studies show levels vary between tea category, leaf size, even whether tea is “bagged” or  loose “leaves.”
    • It appears that for green tea, steeping at cooler temperatures (including cold water) may increase antioxidant levels. (10, 11)

SOURCES

1) The Six Classifications of Tea

2) Tea Association of the U.S.A., Inc.

3) Foods That Fight Cancer

4) Tea and coffee consumption in relation to DNA methylation in four European cohorts

5) Continuous Update Project Report. Diet, Nutrition, Physical Activity and Breast Cancer

6) Bottled tea beverages may contain fewer polyphenols than brewed tea

7) Effects of Infusion Time and Addition of Milk on Content and Absorption of Polyphenols from Black Tea

8) Addition of whole, semiskimmed, and skimmed bovine milk reduces the total antioxidant capacity of black tea

9) The fortification of tea with sweeteners and milk and its effect on in vitro antioxidant potential of tea product and glutathione levels in an animal model

10) Hot vs. cold water steeping of different teas: Do they affect antioxidant activity?

11) Influence of steeping conditions (time, temperature, and particle size) on antioxidant properties and sensory attributes of some white and green teas