Hidden Sources of Caffeine

Caffeine has been linked to hormone-negative breast cancer, including triple negative. And it can lurk unseen in your diet.

I have been having heart palpitations, so I immediately decided that either 1) the chemo had caused heart failure or 2) I have lung cancer, putting pressure on my heart. After an X-ray showed both lungs and heart normal, I decided to get a clue and start looking at my diet to see what I was doing to cause the palpitations. If I could not find an answer, I would go to the doctor, but I suspected I could take care of this by finding culprits in my diet.

I did.

I discovered caffeine all over the place, which is bad news, because I have been avoiding caffeine, as I noted in an earlier post. Caffeine has been linked to increased risk of hormone-negative breast cancer, including triple negative.

What I learned from honestly assessing my diet:

• I had been adding green tea to my morning smoothie, thinking I was adding a jolt of health. I was, but it also came with a jolt of caffeine. I often link green tea to herbal teas and assume it is caffeine-free. In fact, it has less caffeine than black tea and much less than coffee, but it still has caffeine. Thumpety.

• I had been making some nice, strong decaf coffee daily in my French press. That’s OK, right? Wrong. Decaf has less caffeine, but it is not caffeine free. Researchers at the University of Florida compared caffeine in decaf coffee and found that different brands had from 8.6 mg to 13.9 mg, compared to an average of 85 mg for caffeinated coffee. So, the super-strong stuff I was making—and I was making a good 16 ounces of it—no doubt had the caffeine of one or two cups of regular. Add that to the green tea caffeine and I was getting quite a start to my day. Thumpety thump.

• My beloved Diet Coke still hooks me, and when I fall off the wagon, I do a great job. Restaurants give you free refills, right? Sometimes I embarrass myself with the number of times my glass is refilled. There’s about 47 mg, of caffeine in an 12-ounce serving of Diet Coke. Heaven only knows how many I have at a simple lunch. Thumpety thump thump.

• Dark chocolate is considered by some a cancer fighter because of its high levels of antioxidants and phytochemicals. And it has plenty of caffeine: 31 mg in a 1.45 oz, bar. I used to have a tiny square as a treat after a meal. That gradually expanded to 3,4,5 squares. Thumpety thump thump thump.

So, I reminded myself that I am not a bonehead, that I am supposed to be eating healthy, and that I am supposed to know these things. I cut the hidden caffeine from my diet for three days and, guess, what? No palpitations.

I am frankly a bit embarrassed about this, but I am fairly sure I am not the only person who gets caught in the unhealthy caffeine trap. My heart told me to stop. That is way better than a cancer recurrence.

And searching my own diet was far cheaper, easier, and more successful than going in for heart tests.

Nutrition Affects Hormone Negative Disease: An Overview

In her blog, Breast Cancer Information, Kim Dalzell, a doctor of holistic nutrition and registered dietitian,  offers insight into fighting hormone ngative breast cancer. Some of the points she makes:

Women who scored high on Harvard University's Alternate Healthy Eating Index had a lower risk of estrogen receptor negative breast cancer. The guidelines for this index: a daily intake of 9 servings of fruits and veggies, 7 or more grams of dietary fiber, 30-40 percent less saturated fat than polyunsaturated fats, less than 3 grams of trans fats and consuming 1 ounce of nuts. (February 2006, Journal of Nutrition.)

Women whose diets were deficient in folate, a B vitamin, had an increased estrogen receptor negative breast cancer risk. Folate-rich foods include: fruits like cherries, oranges and strawberries, beans and peas, and dark, green leafy veggies. (August 2005, Cancer Epidemiology Biomarkers and Prevention.)

Alcohol robs the body of folate and other B vitamins, so it's prudent to enjoy alcohol only occasionally, if at all. (August 2005, Cancer Epidemiology Biomarkers and Prevention.)

High intakes of linoleic acid were associated with more than a 300 percent greater risk of estrogen receptor negative disease than estrogen receptor positive disease. Linoleic acids are found in polyunsaturated fats like cottonseed, soybean, and corn oil as well as vegetable-based margarines. (The University of Texas MD Anderson Cancer Center research.)

Among premenopausal women, there was a reduced risk of both estrogen receptor negative and estrogen positive breast cancer for those women who consumed the highest lignan intake. Lignans are found in flaxseed, and to a lesser degree in sesame seeds and kale. (Breast Cancer Research Treatment journal, October 2006.)

High-Fiber Bread Associated with Reduced Hormone Negative Risk; Fried Potatoes Associated with Increase

I grew up loving white bread—a piece of lunch meat, some mayo and good old Wonder bread was my idea of the best grade school lunch ever. Yummm. Add some potato chips and it didn’t bother me that I had just tried to recite Joyce Kilmer’s “Trees” and kept starting at the last line and Sister Mary Schoolteacher made me sit down in humiliation. (I kept starting with the final line: “Poems are made by fools like me.” No doubt Sister thought, “Fool indeed.”)

It took me decades to get to truly like whole wheat bread. Fried potatoes remain one of my favorites, although I seldom eat them now. And now I can Google the words to “Trees.” (See below.)

New research shows that I was absolutely on the wrong track for most of my life, but my post-cancer diet is right on the money. Swedish researchers monitored the diets of 544 women for 10.3 years. They discovered that those with a diet that regularly included high-fiber bread had a significantly reduced risk of breast cancer—both hormone negative and hormone positive.

Fried potatoes were significantly associated with an increase in hormone negative breast cancer. Their research was published in August in the journal Carcinogenesis.

So, cut the French fries and chomp on whole wheat bread. Chances are you’ll feel better, fight cancer, and lose weight. Had I done that, maybe I would have recited the poem correctly.

Trees
by Joyce Kilmer

I think that I shall never see

A poem lovely as a tree.
A tree whose hungry mouth is prest

Against the earth’s sweet flowing breast;
A tree that looks at God all day,

And lifts her leafy arms to pray;
A tree that may in Summer wear

A nest of robins in her hair;

Upon whose bosom snow has lain,

Who intimately lives with rain.
Poems are made by fools like me,

But only God can make a tree.

Caffeine Might Increase Hormone Negative Risk

The more caffeine you drink, the higher your risk of hormone negative breast cancer, according to a study published in the October 12, 2008 Archives of Internal Medicine. The research was part of the Women’s Health Study, with 39,310 participants who filled out a comprehensive questionnaire on their eating habits. This study looked at the links between caffeine intake—coffee, black tea, and colas primarily—and breast cancer.

Researchers assumed that the content of caffeine was 137 mg per cup of coffee, 47 mg per cup of tea, 46 mg per can or bottle of cola, and 7 mg per serving of chocolate candy.

The big caffeine Kahuna here, then, is coffee.

Twenty-four percent of the women never drank coffee; 13 percent drank less than a cup a day; 14.2 percent had two to three cups a day, and 15.4 percent had four cups a day. Yikes!

No matter the quantity, though, caffeine had no significant effect on hormone positive breast cancer. But the risk of hormone negative does go up with each cup of coffee. Likewise, the chance of having a tumor larger than 2 cm went up with increased coffee consumption.

Still, as is the case with many breast cancer studies, the number of cases of hormone negative breast cancers was so small that researchers didn’t have enough data to state conclusively that high caffeine leads to hormone negative breast cancer. These findings, they say, may be “due to chance and warrant further study.”

Until the data are in, though, it might be best to cut the coffee.

And, on a side note, most media notices I have read on this focus on the fact that caffeine does not lead to breast cancer, once again making generalizations about breast cancer while ignoring hormone negative.