Does Rye Bread Protect Against Cancer?

Sept 14 Rye Bread copy.jpeg

Previously, I've explored the beneficial effects of flaxseeds on prostate cancer (Flaxseeds vs. Prostate Cancer), as well as breast cancer prevention and survival (Flaxseeds & Breast Cancer Prevention and Breast Cancer Survival & Lignan Intake). The cancer-fighting effect of flaxseeds is thought to be because of the lignans, which are cancer-fighting plant compounds found in red wine, whole grains, greens (cruciferous vegetables), and especially sesame seeds and flaxseeds, the most concentrated source on Earth. But this is based on per unit weight. People eat a lot more grains than seeds. Of the grains people eat, the highest concentration of lignans is found in rye. So, can rye intake decrease the risk of cancer? Theoretically yes, but unlike flaxseeds, it's never been directly put to the test... until now.

In my video Does Rye Bread Protect Against Cancer?, I discuss the evidence that does exist. If you measure the levels of lignans in the bloodstream of women living in a region where they eat lots of rye, the odds of breast cancer in women with the highest levels do seem to be just half that of women with the lowest levels. But lignans are also found in tea and berries, so we couldn't be sure where the protection is coming from. To get around this, researchers decided to measure alkylresorcinol metabolites, a class of phytonutrients relatively unique to whole grains.

Researchers collected urine from women with breast cancer and women without, and the women with breast cancer had significantly lower levels compared to those without. This suggests that women at risk for breast cancer consume significantly lower amounts of whole grains like rye. But if we follow older women in their 50s through 60s, the intake of whole grain products was not associated with risk of breast cancer. A similar result was found in older men for prostate cancer. Is it just too late at that point?

We know from data on dairy that diet in our early life may be important in the development of prostate cancer, particularly around puberty when the prostate grows and matures. If you look at what men were drinking in adolescence, daily milk consumption appeared to triple their risk of advanced prostate cancer later in life. (Learn more about milk and prostate cancer in my video Prostate Cancer and Organic Milk vs. Almond Milk.) So, researchers looked at daily rye bread consumption during adolescence.

Those who consumed rye bread daily as kids did appear to only have half the odds of advanced prostate cancer. This is consistent with immigrant studies suggesting that the first two decades of life may be most important for setting the pattern for cancer development in later life. These findings are certainly important for how we should feed our kids, but if we're already middle-aged, is it too late to change course? To answer this question, researchers in Sweden put it to the test.

Researchers took men with prostate cancer and split them into two groups. One group got lots of rye bread, while the other got lots of high-fiber, but low-lignan, wheat bread. There's been some indirect evidence that rye may be active against prostate cancer--like lower cancer rates in regions with high rye consumption--but it had never been directly investigated... until this study. Biopsies were taken from the subjects' tumors before and after three weeks of bread eating, and the number of cancer cells that were dying off were counted. Though there was no change in the cancer cell clearance of the control bread group, there was a 180% increase in the number of cancer cells being killed off in the rye group. A follow-up study lasting 6 weeks found a 14% decrease in PSA levels, a cancer marker suggesting a shrinkage of the tumor.

The researchers note they used very high rye bread intakes, and it remains to be tested if more normal intake levels would have effects that are of clinical importance. As a sadly typical American, my lack of intimate familiarity of the metric system did not flag the "485 grams" of rye bread a day as far out of the ordinary, but that translates to 15 slices! Rather than eating a loaf a day, the same amount of lignans can be found in a single teaspoon of ground flaxseeds.


I've created several videos on flaxseeds for both breast cancer prevention and treatment, including Flaxseeds & Breast Cancer Prevention, Breast Cancer Survival and Lignan Intake, Flaxseeds & Breast Cancer Survival Epidemiological Evidence, and Flaxseeds & Breast Cancer Survival: Clinical Evidence.

What's more, flaxseeds may help with cyclical breast pain (Flaxseeds for Breast Pain), prostate cancer (Flaxseed vs. Prostate Cancer), diabetes (Flaxseeds vs. Diabetes), and hypertension (Flaxseeds for Hypertension).

And if you're wondering Which Are Better: Chia Seeds or Flaxseeds?, get the answer in the video!

The wonders of whole grains are also discussed in Whole Grains May Work as Well as Drugs, Can Oatmeal Reverse Heart Disease?, and Can Oatmeal Help Fatty Liver Disease?.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Original Link

Does Rye Bread Protect Against Cancer?

Sept 14 Rye Bread copy.jpeg

Previously, I've explored the beneficial effects of flaxseeds on prostate cancer (Flaxseeds vs. Prostate Cancer), as well as breast cancer prevention and survival (Flaxseeds & Breast Cancer Prevention and Breast Cancer Survival & Lignan Intake). The cancer-fighting effect of flaxseeds is thought to be because of the lignans, which are cancer-fighting plant compounds found in red wine, whole grains, greens (cruciferous vegetables), and especially sesame seeds and flaxseeds, the most concentrated source on Earth. But this is based on per unit weight. People eat a lot more grains than seeds. Of the grains people eat, the highest concentration of lignans is found in rye. So, can rye intake decrease the risk of cancer? Theoretically yes, but unlike flaxseeds, it's never been directly put to the test... until now.

In my video Does Rye Bread Protect Against Cancer?, I discuss the evidence that does exist. If you measure the levels of lignans in the bloodstream of women living in a region where they eat lots of rye, the odds of breast cancer in women with the highest levels do seem to be just half that of women with the lowest levels. But lignans are also found in tea and berries, so we couldn't be sure where the protection is coming from. To get around this, researchers decided to measure alkylresorcinol metabolites, a class of phytonutrients relatively unique to whole grains.

Researchers collected urine from women with breast cancer and women without, and the women with breast cancer had significantly lower levels compared to those without. This suggests that women at risk for breast cancer consume significantly lower amounts of whole grains like rye. But if we follow older women in their 50s through 60s, the intake of whole grain products was not associated with risk of breast cancer. A similar result was found in older men for prostate cancer. Is it just too late at that point?

We know from data on dairy that diet in our early life may be important in the development of prostate cancer, particularly around puberty when the prostate grows and matures. If you look at what men were drinking in adolescence, daily milk consumption appeared to triple their risk of advanced prostate cancer later in life. (Learn more about milk and prostate cancer in my video Prostate Cancer and Organic Milk vs. Almond Milk.) So, researchers looked at daily rye bread consumption during adolescence.

Those who consumed rye bread daily as kids did appear to only have half the odds of advanced prostate cancer. This is consistent with immigrant studies suggesting that the first two decades of life may be most important for setting the pattern for cancer development in later life. These findings are certainly important for how we should feed our kids, but if we're already middle-aged, is it too late to change course? To answer this question, researchers in Sweden put it to the test.

Researchers took men with prostate cancer and split them into two groups. One group got lots of rye bread, while the other got lots of high-fiber, but low-lignan, wheat bread. There's been some indirect evidence that rye may be active against prostate cancer--like lower cancer rates in regions with high rye consumption--but it had never been directly investigated... until this study. Biopsies were taken from the subjects' tumors before and after three weeks of bread eating, and the number of cancer cells that were dying off were counted. Though there was no change in the cancer cell clearance of the control bread group, there was a 180% increase in the number of cancer cells being killed off in the rye group. A follow-up study lasting 6 weeks found a 14% decrease in PSA levels, a cancer marker suggesting a shrinkage of the tumor.

The researchers note they used very high rye bread intakes, and it remains to be tested if more normal intake levels would have effects that are of clinical importance. As a sadly typical American, my lack of intimate familiarity of the metric system did not flag the "485 grams" of rye bread a day as far out of the ordinary, but that translates to 15 slices! Rather than eating a loaf a day, the same amount of lignans can be found in a single teaspoon of ground flaxseeds.


I've created several videos on flaxseeds for both breast cancer prevention and treatment, including Flaxseeds & Breast Cancer Prevention, Breast Cancer Survival and Lignan Intake, Flaxseeds & Breast Cancer Survival Epidemiological Evidence, and Flaxseeds & Breast Cancer Survival: Clinical Evidence.

What's more, flaxseeds may help with cyclical breast pain (Flaxseeds for Breast Pain), prostate cancer (Flaxseed vs. Prostate Cancer), diabetes (Flaxseeds vs. Diabetes), and hypertension (Flaxseeds for Hypertension).

And if you're wondering Which Are Better: Chia Seeds or Flaxseeds?, get the answer in the video!

The wonders of whole grains are also discussed in Whole Grains May Work as Well as Drugs, Can Oatmeal Reverse Heart Disease?, and Can Oatmeal Help Fatty Liver Disease?.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Original Link

Flax and Breast Cancer Prevention

 

 

 

 

 

 

 

 

Just a teaspoon of ground flaxseeds a day may help protect against breast cancer.

In 1980 a new compound was discovered in human urine. Researchers called it "compound X." Originally it was thought to be a new human hormone, but it was soon identified as part of a large group of fiber-associated compounds widely distributed in edible plants known as lignans. Vegetarians have about twice the level of lignans circulating within their bodies given their greater intake of plant foods. Since population studies suggested that high intake of lignans reduces breast cancer risk, perhaps lignans are one of the reasons those eating plant-based diets have lower cancer rates.

Where are lignans found most in the diet? Seeds, whole grains, vegetables, fruits and berries. Since these are all really healthy foods in their own right, maybe lignan intake is just acting as a surrogate marker for whole plant food intake? (Like the fiber story I detail in Fiber vs. Breast Cancer). Well, in a petri dish lignans do directly suppress the proliferation of breast cancer cells but only after the plant lignans are converted into human lignans by the bacteria in our gut. (More detail in Flax and Fecal Flora).

That’s why we want to use antibiotics judiciously. A few days on antibiotics dramatically drops our body’s ability to make these anticancer compounds from the plants that we eat, and it can take weeks for our gut bacteria to recover. That may be why women with urinary tract infections have been found to be at higher risk for breast cancer. Every time they took a course of antibiotics they may have been stymying their good bacteria’s ability to take full advantage of all the plants they were eating.

In my 4-min video Flaxseeds & Breast Cancer Prevention I profile the National Cancer Institute study that provides the strongest evidence to date that there might indeed be something special about this class of phytonutrients for breast cancer prevention. They took a bunch of young women at high risk for breast cancer (meaning they had a suspicious breast biopsy showing either atypical hyperplasia or carcinoma in situ, or already had breast cancer in the other breast) and gave them a teaspoon of ground flaxseeds every day for a year before getting a repeat needle biopsy to see if there was any change.

Yes, there are lignans in sesame seeds, nuts, whole grains, legumes, certain fruits, and veggies, but they’re most concentrated in flax seeds. They could have instead asked women to eat ten cups of strawberries a day for a year to get teh equivalent amount, but they’d probably get better compliance with just a teaspoon of flax :)

So what happened by the end of the year? The primary end point was the expression of a proliferation biomarker associated with cancer called ki-67. In 9 of the 45 women it went up, pictured in red in the video, but in the other 80% of the women it went down. And, indeed, on average they found less cellular proliferation in their breast tissue and fewer precancerous changes.

For those that don’t like the taste of flaxseeds, sesame seeds are also high in lignans. Even though flaxseeds have significantly more lignans than sesame, you appear to produce about the same amount of lignans from them. This was, however, comparing them whole. When people are fed whole flaxseeds, some may not be chewed up and can pass right through you. So ground flaxseed may be best overall. As I note in the Flaxseeds For Sensitive Skin video, ground flax stays fresh even at room temperature for at least a month.

What if you or a loved one has already been diagnosed with breast cancer? See my follow-up videos:

-Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live year-in-review presentations Uprooting the Leading Causes of Death and More Than an Apple a Day.

Image credit: kickthebeat / Flickr

Original Link