Reduce Your Breast Cancer Risk With A Plant-based Diet
Breast cancer is the number two killer of women in developed countries. This is a travesty because only 5 to 10% of breast cancer cases are hereditary, leaving the greatest risk by far to lifestyle choices. Learn how to plummet your risk of getting breast cancer by eating more plant-based foods. [WATCH THE VIDEO]
This is an excerpt of a chapter on breast cancer from a book I'm writing about extending healthspan, possibly lifespan as well. To make my blog publication date, I didn't have time to deal with the ornery footnotes here, but know that every claim is substantiated. My thanks to Dr. Michael Greger for the thematic points and approach to this topic.
EVERY YEAR about 230,000 women are diagnosed with breast cancer, and 40,000 die from it. For many women, this is their number one health concern, which makes sense because you might not see it coming. Breast cancer screening does not prevent breast cancer. At best, It can indicate an existing tumor that could be cancerous, but that tumor cold be present for forty years or longer before it’s detected.
Based on autopsy studies, as many as 39% of women in their forties already have breast cancers growing within their bodies that may be simply too small to be detected by mammograms. Scarier yet is that some breast cancers start in the womb as a result of your mother’s diet. And, indeed, diet may be a women’s greatest preventative intervention against getting breast cancer, resisting its metastasis or recurrence. You can’t afford to wait until some diagnosis happens to start.
Is Breast Cancer A Lifestyle Cancer?
As with all cancers or other chronic diseases, the first thing to do is to identify and stop the risk factors that contribute to the disease, and then to begin the protocols that can combat it. According to the The American Institute for Cancer Research (AICR), risk factors to avoid are obesity, inactivity, fast foods and sugars, a meat-dominated diet and alcohol. Lifestyle factors to adopt are the opposite — a healthy weight, physical activity, modest alcohol consumption and a plant-dominated diet. AICR is among the world’s leading authorities on diet and cancer. Its research shows that diets that revolve around whole plant foods— vegetables, whole grains, fruits and beans— cut the risk of many cancers, and other diseases as well.
AICR has established ten cancer prevention recommendations, three of which — limiting alcohol, eating mostly plant foods, and maintaining a normal body weight— was associated with a 60% lower risk of breast cancer.
It turns out that blood tells much of the tale.
Researchers dripped the blood of women before and after fourteen days of healthy living (a plant-based diet and daily walking) on breast cancer cells growing in petri dishes. The blood taken after they started eating healthier suppressed cancer growth much better and killed 20– 30% more cancer cells than the blood taken from the same women just two weeks earlier. The researchers attributed this effect to a decrease in levels of a cancer-promoting growth hormone called IGF-1, likely due to the reduced intake of animal protein.
Alcohol Is A Breast Cancer Risk Factor
Red wine is acceptable, but not much of it. Red grapes with seeds are better.
In 2014 the World Health Organization declared that as concerns breast cancer, no amount of alcohol is safe. Does that really mean that drinking one glass of wine a day will increase your risk of breast cancer? Well, in 2013, scientists published a summary of more than one hundred studies on breast cancer and alcohol consumption in the amount of up to one per day, and found a small but statistically significant increase in breast cancer risk, except perhaps for red wine. The problem with alcohol is the acetaldehyde it contains.
Acetaldehydeis a poisonous byproduct of alcohol metabolism and is a known carcinogenic. It can form in your mouth as soon as you take a sip of alcohol. Experiments show that even holding a single teaspoon of hard liquor in your mouth for five seconds before spitting it out results in the production of potentially carcinogenic levels of acetaldehyde that lingers for more than ten minutes. The good news is that red wine offers a relative safe haven among alcoholic beverages, but is not entirely benign.
Even though the Harvard Nurses’ Health Study found that even less than one drink a day may be associated with a small increase in breast cancer risk, drinking only red wine was not associated with breast cancer risk. This is due to a compound in red wine that appears to suppress the activity of an enzyme called “estrogen synthase”, which breast tumors can use to create estrogen to fuel their own growth. This enzyme-suppressing compound is found in the skin of the dark-purple grapes used to make red wine. White wine confers no such benefit. The researchers concluded that red wine may help negate some of the cancer-causing effects of alcohol.
Least this bit of news presents a rationalization to guzzle bottles of red wine with abandon, know that well before you kill off breast cancer, you’d probably die of alcohol poisoning before red wine eliminated estrogen synthase. A better option to multiple daily glasses of red wine would be to eat red grapes, preferably with seeds, pomegranates and plain white mushrooms may also suppress the potentially cancer-promoting enzyme.
Insufficient Melatonin Is A Breast Cancer Risk Factor
Blind women have just half the risk of breast cancer than sighted women, and the reason is melatonin.
Humans are diurnal animals, and as such our biological systems are tuned to optimally perform during daylight hours. For the overwhelming part of our years as a species, humans did most of their active living during the day. We’ve only been using candles for about five thousand years. Electric lights have enabled us to continue your daytime activities well into the nighttime for only about one hundred years. These days the nights are completely dark only in very rural areas; everywhere else the bright lights of the night brighten the sky. Having illumination on demand is convenient, but has a dark side.
In the middle of your brain rests a small endocrine gland called the pineal gland. It uses the amino acid tryptophan to produce melatonin, a hormone that affects the modulation of wake/sleep patterns and photoperiodic (seasonal) functions. The pineal gland is inactive during daytime hours when there’s ambient light from the sun. At nighttime, assuming you’re not staring at some bright light, your eyes detect reduced light and sends a signal via the optic nerve to the pineal gland, which then executes its one and only function — to produce melatonin. Once melatonin gets absorbed into your bloodstream, you begin to get tired and sleepy.
Melatonin secretion typically peaks between 2: 00 A.M. and 5: 00 A.M. It turns off at daybreak, when once upon a time not so long ago most of our species awoke, irrespective of works schedules. The amount of melatonin in the bloodstream communicates the time to your internal organs and is essential to the regulation of your circadian clock, the 24-hour cycle that tells our bodies when to sleep, rise, and eat, thereby regulating many physiological processes.
Pertinent to our topic at hand, another important role for melatonin is to suppress cancer growth. To test if melatonin might be useful to prevent breast cancer, researchers from Brigham and Women’s Hospital in Boston and their associates astutely came up with the idea of studying blind women. The rationale was that since blind women can’t see sunlight, their pineal glands always secrete melatonin.
Does this change their odds of getting breast cancer as compared to sighted women?
Indeed, what they discovered was that blind women may have just half the odds of breast cancer as sighted women. Conversely, women who interrupt their melatonin production by working night shifts may be at increased risk for breast cancer. Too much artificial light and night might also increase the cancer odds, such as living on a particularly brightly lit street. Studies comparing nighttime satellite photos against breast cancer rates have found that people living in brighter neighborhoods tend to have a higher breast cancer risk.
You can gauge your melatonin production by a test that measures how much of it is excreted by urine first thing in the morning. Women with higher melatonin secretion have been found to have lower rates of breast cancer. To help make sure you have enough melatonin in your system, you can eat more vegetables. In 2005, Japanese researchers reported an association between higher vegetable intake and higher melatonin levels in the urine. In 2009. Researchers at Harvard University asked nearly a thousand women about their consumption of thirty-eight different foods or food groups and measured their morning melatonin levels. For reasons yet to be understood, meat consumption was the only food significantly associated with lower melatonin production.
Heterocyclic Amines Is A Breast Cancer Risk Factor
Overcooked meat produces carcinogens.
The National Cancer Institute describes cancer-producing heterocyclic amines (HCAs) as “chemicals formed when muscle meat, including beef, pork, fish, and poultry, is cooked using high-temperature methods.” You may roast, pan fry, grill or bake the meat, but if it’s cooked too much HCAs are made. Boiling the meat is safer, and the urine and feces of those who consume meat not cooked above 212 degrees Fahrenheit are much less DNA-damaging compared to those eating meat dry-cooked at higher temperatures.
There’s a paradox when it comes to cooking meat. On one hand, we’re encouraged to cook it thoroughly to cut the risk of contracting foodborne infections; well done is best. On the other hand, cooking meat too thoroughly may increase the risk of foodborne carcinogens. Damned if you do, damned if you don’t, it seems. And that’s true for chicken, too. Baking chicken for just fifteen minutes at 350 degrees Fahrenheit leads to HCA production. These carcinogens are formed in a high-temperature chemical reaction between some components of muscle tissue. That doesn’t happen with a veggie burger. Cook it all day long and no HCAs are made. But with meat, the longer it’s cooked, the more HCAs are produced, and that is associated with increased risk of cancers of the breast, colon, esophagus, lung, pancreas, prostate, and stomach.
In 2007, the Long Island Breast Cancer Study Project reported that women who eat more grilled, barbecued, or smoked meats over their lifetimes may have as much as 47% higher odds of breast cancer. The Iowa Women’s Health Study found that women who ate their bacon, beefsteak, and burgers “very well done” had nearly five times the odds of getting breast cancer compared with women who ate these meats served rare or medium. 61 Women that had breast-reduction surgery provided a clue to what was transpiring.
Researchers asked women undergoing breast-reduction surgery about their meat-cooking methods, and were then able to link their fried meat consumption with a type DNA damage in their breast tissue that can potentially cause normal cells to mutate into cancer cells. HCAs seem to be capable of initiating and promoting cancer growth.
One of the most abundant HCAs in cooked meat is called PhIP. It has formidable estrogen-like effects that instigate human breast-cancer cell growth nearly as strongly as pure estrogen on which most human breast tumors thrive. That outcome was based on petri dish research. Least you scoff, “Hey, I don’t live in a petri dish!”, know that cooked-meat carcinogens are also detected in human breast ducts, where most breast cancers arise. PhIP was found in the breast milk of women who ate meat at the same concentration known to significantly boost breast cancer cell growth. No trace of PhIP was found in the breast milk of the one vegetarian participant.
PhIP in meat may represent a three-strikes-you’re-out type of carcinogen, potentially involved in every stage of breast cancer development. Cancer develops in three major stages:
- Initiation, the irreversible DNA damage that starts the process;
- Promotion, the growth and division of the initiated cell into a tumor; and
- Progression, which can involve the invasion of the tumor into surrounding tissue and metastasis (spread) to other areas of the body.
An instrument called an invasion chamber can test how invasive, or aggressive, a certain cancer may be. Cancer cells are placed on one side of a porous membrane and then their ability to penetrate and spread through the membrane is determined. When researchers placed metastatic breast cancer cells from a fifty-four-year-old woman in an invasion chamber all by themselves, relatively few were able to breach the membrane. Within seventy-two hours of adding PhIP to the chamber, however, the cancer cells became more invasive, seeping through the membrane at an accelerated rate. Unfortunately, as the researchers note: “Exposure to PhIP is difficult to avoid because of its presence in many commonly consumed cooked meats, particularly chicken, beef and fish.”
Cholesterol Is A Breast Cancer Risk Factor
High LDL cholesterol feeds cancer cells.
You know that cholesterol plays an important role in heart disease (see my Heart Disease write-up). Surprisingly, it’s a factor in breast cancer as well, as cancer may feed on cholesterol, at least in a petri dish. When LDL cholesterol is placed in a petri dish containing cancer cells, they greedily consume the LDL. Tumors seem to consume so much cholesterol that cancer patients’ cholesterol levels nosedive as their cancer grows. The current consensus is that the cancer is using the LDL cholesterol to make estrogen or buttress tumor membranes to help the cancer spread, which implies that breast tumors may use high circulating LDL to fuel and augment their own growth.
Cancer’s appetite for LDL cholesterol has not gone unnoticed by pharmaceutical companies. Some are testing if cholesterol could be used to deliver anti-tumor drugs to cancer cells. Other studies have investigated if the statin drugs used to lower cholesterol might also cut breast cancer risk. After some inconclusive results from studies deemed to be too short-term, the first major long-term study on breast cancer risk of statin use for ten years or longer was published in 2013, and found that statins doubled the risk. Women on statins for a decade or more had twice the risk of two types of breast cancer, invasive ductal carcinoma and invasive lobular carcinoma.
The public health implications of these findings are overwhelming, given that about 25% of women in the U.S. older than forty-five are subscribed statins. Given that LDL cholesterol can be a risk factor for both heart disease (the number-one killer of women and men) and breast cancer (the number-two killer of women), you have excellent reasons to reduce your LDL, and that can be done without statins by embracing a plant-based diet.
A Meat-dominate Diet Is A Breast Cancer Risk Factor
Broccoli and brussels sprouts help to clear the carcinogenic heterocyclic amines.
Despite all I’ve written about the health benefits of consuming plants, my intent is not to make you a vegetarian or vegan, but rather to convince you that eating more plant-based foods is in your interest. One simple thing you could do is at every meal fill at least two-thirds of your plate with plant foods and one-third or less with animal foods. In addition, consider making soups and stews consisting of beans or lentils mixed with a plentiful amounts of cruciferous vegetables and kale. (Soak the beans and lentils overnight to rid them of phytic acids and lectins.)
In a pinch, make a smoothie consisting of various vegetables (spinach, kale, cauliflower), berries, almond milk, seeds (sunflower, hemp and/or chia) and protein powder (hemp, rice or pea; or if after a muscle-fatiguing workout, whey protein). The point is to add plant-based foods to your diet when you can, and cut your consumption of meat.
I’ve presented plenty of reasons why reducing meat consumption can improve your health overall, and reduce breast cancer risk. But there’s more.
In the 2007 Long Island study that linked breast cancer risk to the heterocyclic amines (HCAs) formed in meat, it was found that older women who ate the most grilled, barbecued, or smoked meat over their lifetimes were found to have 47% increased odds of breast cancer. Those with high meat intake who also had low fruit and vegetable intake had 74% higher odds. Low fruit and vegetable intake may just be a sign of unhealthy habits overall, but increasing evidence suggests that there may be something in produce that is actively protective against breast cancer. For example, cruciferous vegetables like broccoli boost the activity of detoxifying enzymes in your liver.
Research indicates that broccoli and brussels sprouts help to clear the carcinogenic heterocyclic amines circulating in the bodies of meat eaters. They fed non-smokers pan-fried meat and then measured HCAs in their bodies by sampling their urine. Over the course of two weeks, the study subjects added three cups of broccoli and brussels sprouts to their daily diets, and then ate the meat meal. What they found was that not only did the broccoli and brussels sprouts boost the livers’ detox capabilities as measured by the presence of HCAs in the subjects’ urine, but their liver function remained enhanced even weeks after these cruciferous plants were consumed. Your takeaway from this is that your decision is that you don’t have to completely excise meat from your diet, but to:
- Not overcook it;
- Eat less of it; and
- Eat more plant foods, especially cruciferous vegetables.
Broccoli Sprouts Are Mana From Heaven
A super duper superfood.
If you had to choose just one plant-based food to eat to maximize your healthspan, if not your lifespan, my suggestion is that you select broccoli sprouts.
Cruciferous plants contain compounds called glucosinolate, which convert into isothiocyanates when eaten and chewed. All cruciferous veggies contain glucosinolates, but broccoli sprouts have an insane amount — about 10 to 100 times more than most cruciferous vegetables. They also contain a compound within the isothiocyanate group of organosulfur compounds (organic compounds that contain sulfur) called “sulforaphane”, which is especially potent. There’s evidence to suggest that sulforaphane can prevent DNA damage that leads to cancer, and in studies on mice, sulforaphane seems to prevent inflammation that can lead to neurodegenerative diseases, like Alzheimer’s and Huntington’s disease.
Next up is a video explaining the marvels of broccoli sprouts by Dr. Rhonda Patrick, who walks her talk:
Rather not sprout your own? Then check out:
Now to Dr. Patrick’s video:
00:01:14 – Cancer and mortality
00:19:04 – Aging
00:26:30 – Brain and behavior
00:38:06 – Final recap
00:40:27 – Dose
I’ll end with this request: If you know a woman over 40 years of age, send her this article.