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Caffeine: Drink (Moderately) to Your Health

By on October 22nd, 2014 Categories: Uncategorized

When it comes to staying healthy, we hear the words “don’t” and “avoid” a lot. “Avoid alcohol.” “Don’t smoke.” “Don’t eat trans fats.”

I also think that some of the “dos” (“Do eat lots of leafy greens.” “Do drink water.”) seem kind of boring and not much fun. So I was glad to learn that my favorite pick-me-ups — coffee, tea, and cocoa — are something I can say yes to in moderation.

More than 50% of American adults drink coffee daily — around 3 cups per day. My day officially starts with my one and only caffeinated drink: a big, strong cup of coffee. The reality is that coffee is an over-the-counter medication that doesn’t require a prescription. While caffeinated beverages may seem necessary to function in today’s somewhat hectic world, they’ve been enjoyed for centuries in many cultures around the globe.

The energy- and mood-boosting effects of coffee, tea, and cocoa come from the many naturally occurring chemicals found in the beans and leaves we use to brew them. One group of compounds is methylxanthines (meth-ill-ZAN-theenz) and includes caffeine (found in all three drinks). Another methylxanthine is theobromine, which is found in cocoa. Tea and cocoa are rich in another group of plant chemicals called polyphenols.

It turns out these plant chemicals have health properties that last longer than the energy boost. Studies are looking at how these plant chemicals affect how our cells function, which can affect how diseases develop and spread. Research in petri dishes in the lab suggests that these plant compounds may help protect our bodies against various types of cancers and also help fight other conditions. Still, much more human research needs to be done before any prevention claims can be made for caffeinated beverages.

The U.S. Food and Drug Administration says drinking up to 4 cups (32 ounces) per day is considered safe for most healthy adults. So if you enjoy coffee, tea, or cocoa, there seems to be no harm for most people.

Talk to your doctor if you have high blood pressure, osteoporosis, or type 2 diabetes. Too much caffeine can interfere with treatments for these conditions because it increases blood pressure, leaches bone calcium, and raises blood sugar in some people. Also, ask your doctor about possible interactions with any medicines you may be taking, such as certain antibiotics, the bronchodilator theophylline, or the herb echinacea.

One important note about caffeinated beverages: It’s best to avoid processed commercial drinks with added caffeine. Soda and energy drinks and shots don’t offer the same benefits as plant-based beverages. Also, it’s not clear if they’re safe to consume over long periods of time or if they cause health problems.

The effects of caffeine

Caffeine affects many systems in the body:

  • central nervous system
  • cardiovascular system
  • respiratory system
  • metabolic system
  • gastrointestinal tract
  • urinary tract

That’s because it blocks the action of adenosine, a chemical our body makes that helps to move energy in the body as well as to regulate blood flow to the organs. When adenosine is blocked, one result is feeling awake, focused, and more upbeat.

Still, the effects of caffeine are very different in different people. Some people feel nervous or get heartburn, even if they’re only drinking decaffeinated beverages.

While caffeine is commonly used as a stimulant — to keep you focused, awake, and alert — overstimulation can interfere with sleep. I’m very sensitive to caffeine. It keeps me up at night — making my menopause- and tamoxifen-related insomnia worse. So, even though I LOVE coffee, I can only drink one strong cup in the morning. Sadly, I can never have coffee after noon.

How long the effects of caffeine last depends on how big a dose of caffeine you take in and how fast your body breaks it down — again, everyone is different. It can take anywhere from 5 to 7 hours, on average, for half the caffeine you’ve drunk to leave your body. So, for example, my 8-ounce cup of strong coffee probably contains around 200 mg of caffeine. If I have my cup of coffee at 10 a.m., then I still have 50% of the caffeine left at 5 p.m. (100 mg), and 25% left at midnight (around 50 mg). And that darn 50 mg, along with my hot flashes, can keep me up.

Caffeine and breast health

Any health effects of caffeine are more complicated when we look at breast health or breast cancer. You may have heard that you should avoid coffee and tea because the caffeine encourages the growth of benign breast lumps. The latest research has found there’s no connection between caffeine and the development of breast lumps for women in general (each individual may have her own unique pattern or reaction).

When it comes to any relationship between caffeine and breast cancer, the research done so far is very early. Overall, people who drink caffeinated beverages seem to have no increase in the risk of being diagnosed with breast cancer. Caffeinated beverages also don’t seem to affect survival in people who’ve been diagnosed.

You can find studies that show a possible slight benefit, no effect, or a possible slight harm. Lab studies suggest that methylxanthines may have breast-cancer protective effects. Everyday amounts of caffeine seem to suppress the growth of cancer cells in the lab. A review of many studies of caffeine drinkers found that for each 200 mg of caffeine drunk, there was a 1% drop in breast-cancer risk. Still, other human studies suggest that caffeine can either suppress or promote breast cancer cells, and that higher levels of caffeine in the diet slightly increased the risk of hormone-receptor-negative breast cancers.

It’s important to know that all these results are early. It’s also likely that other factors, such as a person’s overall health, age, diet, weight, and lifestyle factors such as smoking and drinking alcohol are affecting any relationship between caffeine and breast cancer. Much more research needs to be done before we understand any possible protective links between caffeine and cancer.

Also, caffeine is just one of the many compounds in coffee, tea, and cocoa. They are all complex substances. Since most of us like one more than the others, let’s look at them separately.

What’s in your cup?

Coffee: Drinking coffee first became popular during the Middle Ages, when Arab and European people began roasting the beans of tropical plants in the Rubiaceae family. Brewed coffee is high in caffeine — it contains about 12 mg to 25 mg per ounce of liquid. How much depends on the brand, bean roast, brew strength, and brewing method. (Decaf coffee does have a small amount of caffeine.)

Some of the encouraging findings on coffee and breast cancer suggest that coffee raises levels of compounds that reduce the risk of hormone-receptor-negative breast cancer. Drinking moderate to large amounts of coffee also was found to help prevent breast cancer recurrence in people taking tamoxifen. In that study, women who drank a lot of coffee had breast cancer recurrence rates that were less than half the rate of women who drank one or fewer cups daily. Some early research also suggests that coffee drinkers with an abnormal BRCA1 gene have a lower risk of developing breast cancer.

Tea: Tea has been drunk for pleasure and used in Chinese medicine for around 5,000 years. Today, it’s the most-consumed drink in the world after water. When I say “tea,” I mean caffeine-containing drinks made from the Camellia sinensis plant. Herbal teas made by steeping the roots, leaves, stems, and fruits of other plants are nice but not the same.

There are three main types of tea: black, green, and oolong. Each is grown and processed differently. Growers let the leaves dry and absorb oxygen from the air (called oxidation) for different amounts of time. Black tea is fully oxidized, oolong is partially oxidized, and green tea is hardly oxidized at all. The more oxidized your tea, the more caffeine it contains. Black tea has about 70 mg of caffeine per 8-oz. cup (about half the amount in coffee), while the same size cup of green tea has up to 45 mg of caffeine.

All teas contain antioxidants called polyphenols, plant chemicals that have health benefits. Polyphenols help fix cell damage caused by free radicals. (Free radical molecules increase inflammation in the body.) These plant chemicals also affect the color and taste of the tea.

Research suggests that tea polyphenols and tea itself have powerful protective effects against cancer. Besides fighting free radicals, they help keep cells healthy and prevent mutations, abnormal changes in cells that can lead to disease. Certain polyphenols in tea seem to act like vitamin C by stopping harmful reactions in the body.

Tea also contains an amino acid called theanine. Research suggests that theanine may promote anti-cancer mechanisms in the body. The highest levels of theanine are found in black tea and the lowest in green. Theanine also contributes to tea’s soothing effect.

Research results on tea-drinking and breast cancer have been inconsistent. Some studies show benefits, but much research shows no relationship between tea and reduced risk.

Cocoa: When I say “cocoa,” I’m talking about the ground seeds of the cacao tree. People began using cocoa about 3,000 years ago in the Amazon, where it was a big part of Maya and Aztec culture. Many people, including me, crave chocolate, and we may be on to something!

Besides the methylxanthines caffeine and theobromine, cocoa contains many antioxidants that can help prevent cell damage and may even lower the risk of cancer starting. Compounds in cocoa also have been shown to protect against inflammation and there is also evidence that certain cocoa compounds help reduce the risk of heart disease. Still, this doesn’t mean you should start chugging Swiss Miss. While the research on cocoa seems to have positive health benefits, there’s no clear impact on breast cancer risk. I take this as good news: another wonderfully delicious “vegetable” (it comes from a bean, right?!) for us to enjoy. Still I have to watch the calories, because there is direct proof that extra weight is unhealthy and can increase the risk of breast cancer risk and recurrence.

Tips for drinking caffeinated beverages

  • Enjoy up to about four cups (400 mg) of caffeinated coffee or black, green, or oolong tea per day.
  • Pay attention to roast and preparation. Dark roast coffee has less caffeine than light roast because the beans have been heated longer. It’s the opposite after you add water: The longer you brew your coffee or tea, the more caffeine it contains. That’s why drip and percolator coffee and brewed tea have more caffeine than instant or espresso.
  • Drink hot brewed tea if you want your full share of polyphenols. Iced, bottled, and decaf teas contain less of these plant compounds.
  • Take your coffee or tea black, which has zero calories. If you like milk, cream, and/or sugar, use them in moderation. Try to avoid processed, non-dairy “creamers” and artificial sweeteners. And hold the flavored syrups and whipped topping! Fat-and calorie-laden coffee shop treats can lead to weight gain, which is a breast cancer risk.
  • Make hot cocoa using unsweetened cocoa powder or shavings of very dark, organic bar chocolate (60% to 85% cocoa). For the liquid, try reduced-fat or almond milk and just a bit of sugar to keep calories and fat in check.
  • Know your limits and practice moderation. When it comes to caffeine intake, there is no one-size-fits-all. While one cup of coffee may barely affect your friend, the same serving may keep you up all night. Drinking tea all day or sipping an evening espresso could affect your sleep. (See my column Sleep Tight, Slim Down on why slumber is so important for cancer prevention and overall health.) If you can’t say no, try switching to decaf. (Brewed decaf still has about 2-12 mg caffeine, however.)
  • Pay attention to side effects. Caffeine can cause stomach upset, heartburn, or bladder irritation in some people. It also makes some people anxious. If that’s you, you may want to cut back or give it up.
  • Be aware of caffeine-withdrawal syndrome. Stopping suddenly can give you headaches, make you feel drowsy or blue, or cause constipation. Fortunately, the symptoms are temporary.
  • Many people depend on caffeine to wake up both them and their bowels. If you cut back on caffeine, you may need to up your fluid and prune intake to offset the drop in caffeine and keep things moving.

Are you a coffee, tea, or cocoa drinker? What’s your favorite way to make your beverage of choice?

Marisa Weiss, M.D. is the founder, president, and chief medical officer of Breastcancer.org, the world's most trafficked online resource for medically reviewed breast health and breast cancer information, reaching over 14 million visitors per year. A breast cancer oncologist with over twenty years of active practice in the Philadelphia region, Dr. Weiss is regarded as a visionary advocate for her innovative and steadfast approach to informing, empowering, and treating patients with breast cancer.

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