October is Breast Cancer Awareness Month, but eating healthy all year round can reduce your lifetime risk of the disease. Reducing your risk of breast cancer may be as simple as choosing a whole-food, plant-based diet, including these nine foods that have been shown in studies to drive down breast cancer risk. Breast cancer is the number one cancer among women in the U.S., afflicting about 276,000 women a year, or one in every eight women over their lifetime, which is why so many of us are searching for ways to reduce the risk of a breast cancer diagnosis.

On a positive note, when detected in the earliest stages breast cancer is 99 percent treatable to a five-year cure. Even better news: To be clear, nothing you eat directly causes or prevents cancer, but new research shows that you can lower your risk by the lifestyle choices you make.

"Preventative dietary measures include reducing the intake of alcohol, red meat, and fat while increasing intake of fiber and vitamin D as well as phytoestrogens from various food sources," according to one study that looked at the role of diet and breast cancer risk. All in all, nutrition impacts 35 percent of all breast cancer cases, the study found.

This study specifically links meat and dairy to an elevated risk of breast cancer: Women who ate just one-quarter of a cup of full-fat milk or dairy a day had an increased risk of breast cancer. Doctors encourage patients to adopt a healthy lifestyle of daily exercise and a minimally processed, low-fat diet rich in fruits, vegetables, grains, and beans. Whole foods, high in fiber and rich in antioxidants are crucial to reducing the risk of breast cancer.

Adding more fiber and antioxidants to your diet is the best way to reduce your risk of breast cancer. The best part is you may be eating these foods on a daily basis already. Here are the best antioxidant-rich and fiber-packed foods to reduce your risk of breast cancer, according to the latest studies.

A High Fiber Diet and Breast Cancer

Decreasing the number of fatty foods in your diet and replacing them with whole foods will reduce your risk and have been shown to improve the survival rate of breast cancer patients. One study showed that a low-fat diet reduces the risk of death from breast cancer by 21 percent. Adding fiber and antioxidants–found in fruit and vegetables–to a diet low in animal fat is optimal for breast health. Women on a high-fiber diet were 8 percent less likely to develop breast cancer, compared to those who ate less fiber. An increase in dietary fiber lowers blood sugar and estrogen levels in the body, which is key to slowing or halting tumor growth.

Fiber-rich foods typically are also high in antioxidants, which are not only important for preventing breast cancer but in treating it as well. Antioxidants contain nutrients that boost your immune system and protect against free radicals, which are molecules that damage tissue and can lead to cancer growth. Antioxidants also block the cancer-causing effects of carcinogens and can help women in remission lower their risk of reoccurrence.

So whether you're genetically predisposed by having one of the genetic markers, recently diagnosed for the first time, or are recovering from breast cancer treatment, a plant-based diet is known to improve breast health, according to a growing number of recent studies. Here are nine plant-based foods that can help to lower your risk of breast cancer, according to studies.

9 Foods That Can Help Lower Breast Cancer Risk

Healthy kale and quinoa salad
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1. Dark leafy greens like broccoli, kale, and other cruciferous vegetables

Dark leafy greens, such as broccoli and kale contain a chemical called sulforaphane that has anti-cancer properties, according to studies. One study found that sulforaphane in broccoli not only possesses anti-cancer properties but also restricts tumors from growing in the lab and can prevent cancer from spreading.

Kale is packed with antioxidants since it is high in vitamin C with 80 mg in one cup, which prevents cancer from forming in the lab. Research showed the carotenoids in kale can boost the body's immunity against diseases and stop free radicals from damaging cells that can lead to cancer growth. Women who ate the most carotenoids had the lowest levels of cancer in that study. Carotenoids are found in vegetables such as carrots, corn, and tomatoes

Bowl of Japanese eggplant with tofu
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2. Soy foods like tofu and edamame

This may come as a shocker to most people, but soy foods don't increase the risk of cancer, new studies have found, but may even help to prevent it. Incorporating soy foods like tofu, miso, edamame, and soy milk once a day for over a lifetime reduces the risk of breast cancer because the phytoestrogens that mimic estrogen actually suppress the amount of actual estrogen in the body.

Isoflavones are the soy protein often linked to breast cancer but whole food sources, such as tofu don't have high enough levels of it to trigger cancer growth. Soy supplements are known to have high levels of Isoflavones, so if breast cancer runs in your family, you may want to stay away from concentrated levels or supplements. A small amount of plant-based phytoestrogens appear to be protective, so your best bet may be to just eat a regular serving of edamame or tofu a day.

Blueberry smoothie in glass
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3. Blueberries and other deep-hued berries

Berries are rich in antioxidants and contain anti-inflammatory properties, and the most powerful berry to fight against breast cancer is blueberries. Blueberries improve brain and heart health as well as reduce cancer risk and are high in fiber, vitamin C, vitamin K, and flavonols, which are helpful compounds that work to detox the body from pollutants and cellular damage from free radicals.

Studies show that phytochemicals and nutrients increase antioxidant activity in the blood and help your body repair cell damage that can lead to cancer growth as well as prevent DNA damage on a cellular level. Eating berries and deep-hued fruits and vegetables every day help your body stay on top of the cellular damage caused by the stress of oxidization that comes from toxins in the environment or the food we eat.

Close-Up Of Green Tea In Cup On Table
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4. Green tea

Researchers discovered that women in Asia are about 5 times less likely to develop breast cancer than those who live in North America. Possible explanations include the fact that green tea consumption is higher in Asia and has been found to decrease risk by about 30%,

In one study, researchers discovered that those who drink one cup of green tea daily have a lower overall risk of cancer. Doctors stress that patients shouldn't substitute green tea for any cancer treatments or medications but should opt to drink one glass daily along with their regular course of treatment. The antioxidant, EGCG in green tea is what makes this hot beverage so powerful: A study showed that an EGCG supplement can decrease breast density in young women, which in turn reduced the risk of cancer.

Whole and peeled walnuts.
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5. Walnuts

"Walnuts contain multiple ingredients that, individually, have been shown to slow cancer growth, including omega-3 fatty acids, antioxidants, and phytosterols," says one leading study. "In previous research, consumption of walnuts has slowed the growth of implanted breast cancers."

Omega-3 fatty acids have been shown to help fight inflammation which in itself is beneficial in avoiding heart disease and a host of other chronic conditions, but it is also linked to cancer. One study showed that adding walnuts to your meals daily may slow the growth of breast tumors. Walnuts are the most studied nuts and researchers believe that even seven whole walnuts a day are enough to pack major health benefits. Specifically, nutrients such as ellagitannins, melatonin, and gamma-tocopherol in walnuts are believed to reduce oxidative stress and inflammation, which can ultimately lead to cancer growth.

Sauteed white mushrooms with buckwheat in wooden bowl
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6. White mushrooms

In the lab, "white mushrooms have been shown to block estrogen synthase enzymes which fuel tumor growth, and researchers found that when comparing 1,000 breast cancer patients to the same number of healthy controls, those who ate more than just one half of a mushroom per day experienced a 64 percent risk reduction over women who ate no mushrooms," a study found. This powerful effect from such a tiny amount makes us want to eat mushrooms every day of our lives. Sneak them into your smoothie or salad!

Onion,garlic, parsley and rosemary
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7. Garlic and onions

Eating garlic and onions in large quantities may protect against breast cancer, according to a new study out of Puerto Rico. The authors looked at women 30 to 79 and found that those who ate "moderate to large" amounts of garlic and onions had the lowest rates of breast cancer. Other cancer risks were also found to be lower, including lung, stomach, and prostate, possibly due to the flavonols and organosulfur in garlic and onions which have been shown to prevent cancer cell growth.

Sofrito, a popular base in Latin American cuisines, uses tons of garlic and onion along with a variety of peppers. The study found those who consumed sofrito once per day had a 67 percent reduced risk, compared to those who never consumed it. Researchers found that Puerto Rico, where garlic and onion are a staple of the cuisine, has the lowest breast cancer rate among women in the U.S.

Jamu Indonesian drink with natural ingredients turmeric, ginger, lemon on white background. Close up.
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8. Curcumin

Curcumin, the main active ingredient in turmeric, is known for relieving inflammation and pain but also for having an effect on lowering the risk of breast cancer. A study found "curcumin has chemopreventive and antitumoral activities against some aggressive and recurrent cancers," the study said. Another study found curcumin not only stops tumor growth but also prevents malignant cancers from spreading: The "anticancer effect"  of curcumin relates to the fact that it appears to half "cell cycle and proliferation," as well as "cancer spread and angiogenesis," the study says, which is how the body supplies new blood vessels to a tumor.

Green Smoothie Bowl

9. Flaxseeds

Flaxseeds are high in alpha-Linolenic acid (ALA), which is an omega-3 fatty acid, and the antioxidant lignan. Studies have shown that women who eat a diet high in omega-3 have a reduced risk of breast cancer and complications around cancer, according to the latest research.  In a 2018 study on mice, omega-3 in fish oil stopped breast cancer tumors from spreading and elongated the life of the animals. So researchers were able to conclude that omega-3 is important when it comes to preventing the growth of breast cancer in the lab.

Yet another study showed ALA in flaxseeds can suppress the growth size and spread of cancer cells. The high content of lignans in flax seeds converts into phytoestrogens, which can decrease cell growth, this research showed. Studies also indicate that flaxseeds combined with tamoxifen, a medication used to help prevent the recurrence of breast cancer, can help reduce tumor size more effectively than when tamoxifen is taken alone.

Foods That Are Linked to Breast Cancer

Studies say that along with avoiding meat and full-fat dairy, you should stay away from all fried foods, pre-packaged baked goods, and junk food to cut down on saturated fats and trans fats in your diet as well as lowering your alcohol intake. Alcohol consumption has been known to increase estrogen levels in women and just three drinks a week is enough to increase your risk of breast cancer by 15 percent.

Meat is not only high in fat but when it gets cooked at high temperatures it releases toxins that are known to cause cancer. Processed meats and cold cuts are high in fat, salt, and preservatives, meaning you should limit or avoid intake to lower your cancer risk.  The same study that found drinking 1/4 of a cup of milk led to a 30 percent increase in the risk of breast cancer also discovered that drinking one full cup of milk per day drives up your risk from 30 percent to 50 percent. So the more milk you drink, the higher your breast cancer risk.

An overall healthy, balanced diet filled with whole plant-based foods is proven to be the most beneficial for overall breast health and reduces your lifetime risk of developing breast cancer. We'll see you in the produce aisle, buying mushrooms.

For more research-backed content, visit The Beet's Health & Nutrition articles.

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