AICR'S FOODS THAT FIGHT CANCER

No single food or food component can protect you against cancer by itself. But research shows that a diet filled with a variety of vegetables, fruits, whole grains, beans and other plant foods helps lower risk for many cancers.

Foods Can Fight Cancer Both Directly …In laboratory studies, many individual minerals, vitamins and phytochemicals demonstrate anti-cancer effects. Evidence suggests it is the synergy of compounds in the overall diet that offers the strongest cancer protection.

… And IndirectlyAICR research finds that excess body fat increases the risk of 11 cancers. Vegetables and fruits are relatively low in calories. Whole grains and beans are rich in fiber, which also can help with weight management. That is one reason AICR recommends filling at least 2/3 of your plate with plant foods.

Research on foods that fight cancer – and that may also aid cancer survival – is ongoing and active.

The Cancer ResearchOne apple provides at least 10 percent of the recommended daily amount of vitamin C and fiber. Dietary fiber can act in several ways to lower cancer risk, including helping with weight control. (Excess body fat increases the risk of ten different cancers, and dietary fiber can increase the feeling of fullness.) Gut bacteria can use pectin, a major portion of apples’ dietary fiber, to produce compounds that protect colon cells.

Apples also contain a variety of phytochemicals that scientists are studying for their anti-cancer effects. The peel of the apple contains a third or more of its phytochemical compounds. About 80 percent of quercetin, for example, is located in the peel.

What Current Evidence Shows: AICR/WCRF Expert Report and its Updates (CUP)Apples are fruits that contain dietary fiber. After a systematic review of the global scientific literature, AICR/WCRF weighed the strength of the evidence linking these factors to lower risk for several cancers.

Diets high in: CONVINCINGLY lower risk of the following cancers:Foods containing dietary fiber ColorectalDiets high in: PROBABLY lower risk of the following cancers:Fruits Mouth, Pharynx, LarynxLungSource: Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective and the 2011 Continuous Update Project (CUP): Colorectal Cancer.

”Research is pointing to the fact there is not one single phytochemical that supplies apples’ anti-cancer properties... It’s the whole apple.” - Rui Hai Liu, Cornell University.

AICR'S FOODS THAT FIGHT CANCER™Blueberries

BlueberriesThe blueberry is one of the few fruits native to North America. Native Americans used the berries and parts of the plant for medicine. Today, blueberries have a rockstar reputation among fruits; one popular claim is that blueberries help reduce age-related memory loss. It's too early to know whether that's true, but we do know they contain powerful phytochemicals called anthocyanins, which give these berries their blue color.

What's in Blueberries?Blueberries are an excellent source of vitamins C and K, manganese and a good source of dietary fiber. Blueberries are among the fruits highest in antioxidant power, largely due to their many phytochemicals:• Anthocyanins, catechins, quercetin, kaempferol and other flavonoids• Ellagitannins and ellagic acid• Pterostilbene and resveratrol

The Cancer ResearchBlueberries contain numerous phytochemicals and nutrients, many of which are well studied in the laboratory. They also contain dietary fiber, which can act in several ways to lower cancer risk, including helping with weight control. Excess body fat increases the risk of seven different cancers, and dietary fiber can increase the feeling of fullness.

Open Areas of Investigation: Laboratory ResearchLaboratory research is extensive on blueberry compounds such as flavonoids and ellagic acid.Vitamin C protects cells’ DNA by trapping free radicals and inhibiting formation of carcinogens.In cell studies, blueberry extract and anthocyanins, as well as ellagic acid and the urolithins that form from it, decrease free radical damage to DNA that can lead to cancer. They also decrease growth and stimulate self-destruction of mouth, breast, colon and prostate cancer cells.In animal studies, blueberries decrease inflammatory cytokines, esophageal cancer and pre-cancerous changes in the colon, although impact on colon cancer is less clear. In other animal studies, blueberries decrease estrogen-induced mammary cancer and DNA damage.Pterostilbene increases self-destruction of lung, stomach, pancreatic and breast cancer cells. In an animal study, it also decreased formation of pre-cancerous colon polyps and reduced markers of inflammation.Dietary fiber reduces cells’ exposure to cancer-causing substances, and healthful gut bacteria use it to produce short-chain fatty acids that protect colon cells.

Broccoli & Cruciferous VegetablesThe four-petal flowers from these veggies resemble a cross or "crucifer," hence the name. Broccoli is probably the best known cruciferous vegetable. Like Brussels sprouts, rapini, cabbage, cauliflower and turnips (white), it forms a "head." Others - known as the "headless crucifers" - include dark green leafy vegetables like kale and collard greens.

What's in Cruciferous Vegetables?Nearly all are excellent or good sources of vitamin C and some are good sources of manganese. Dark greens are high in vitamin K.

Glucosinolates are compounds found in all cruciferous vegetables; Glucosinolates form isothiocyanates and indoles.Other nutrients and phytochemicals vary:

• Broccoli, Brussels sprouts, cauliflower and rapini are all excellent sources of folate, a B vitamin.• Broccoli is a good source of potassium.• Broccoli and Brussels sprouts are good sources of dietary fiber and rich in magnesium.• Broccoli, Brussels sprouts and rapini contain carotenoids such as beta-carotene.• Red cabbage and radishes supply anthocyanins Other cruciferous vegetables provide different polyphenols, such as hydroxycinnamic acids,

kaempferol and quercetin.Open Areas of Investigation: Laboratory Research Cruciferous vegetables are a large group, and each kind contains numerous vitamins, minerals and phytochemicals studied in the lab for cancer protection. Some of the more well-studied compounds include:

• Glucosinolates, which are broken down into isothiocyanates and indoles. Lab studies have shown these compounds decrease inflammation, a risk factor for cancer. Thecompounds also inhibit enzymes that activate carcinogens and stimulate enzymes that de-activate carcinogens. Studies suggest the compounds "turn on" genes that suppresstumors, slowing cancer cell growth and stimulating a process called apoptosis in which cancer cells self-destruct. Some studies show that these substances may also shift theactive form of estrogen into a weaker form. (High amounts of estrogen are a risk factor for certain hormone-linked cancers.)

• Carotenoids act as antioxidants. Beta-carotene, one of the more well-known carotenoids, also promotes cell communication that helps control abnormal cell growth.• Vitamin C protects cells as an antioxidant and by supporting the immune system.• Kaempferol, quercetin and anthocyanins provide antioxidant and anti-inflammatory effects. In cell and animal studies, they slow development of several stages and types of

cancer.

CarrotsPeople have been eating carrots for some 5,000 years, reportedly starting in the Middle East and Afghanistan. These early carrots were purple and yellow. Our familiar orange carrot was probably developed in the 1600s in Holland.

Today, carrots are among the most popular vegetables in the US. The bagged baby carrots helped spur their popularity when they were developed in the 1980s. (These aren't young carrots - they come from larger ones cut to the smaller size.) You can also find carrots in purples, reds and yellows, each with their own unique mix of phytochemicals.

What Current Evidence Shows: AICR/WCRF's Expert Report and its Updates (CUP)Carrots are a non-starchy vegetable that contain fiber and carotenoids. After a systematic review of the global scientific literature, AICR/WCRF weighed the strength of the evidence linking these factors to lower risk for several cancers.

Diets high in: CONVINCINGLY lower risk of the following cancers:Foods containing dietary fiber ColorectalDiets high in: PROBABLY lower risk of the following cancers:Non-starchy vegetables Mouth, larynx, pharynxCarotenoids Mouth, larynx, pharynxLungsOpen Areas of Investigation: Laboratory ResearchIn addition to their roles as antioxidants, beta-carotene and alpha-carotene promote cell-to-cell communication, which seems important in maintaining normal control of cell growth.

Luteolin and falcarinol, also found in carrots, decrease cancer cell growth and increase cancer cell death in cell and animal studies.

What's in Cherries? The Cancer ResearchCherries contain numerous phytochemicals and nutrients, many of which are well studied in the laboratory. They also contain dietary fiber, which is linked to lower risk of colorectal cancer. Consuming high amounts of dietary fiber may also help people control their weight by giving a feeling of fullness. That is important to cancer risk because excess body fat increases the risk of eleven cancers.

What Current Evidence Shows: AICR/WCRF expert report and its Continuous Updates (CUP)Cherries are fruits that contain dietary fiber. After a systematic review of the global scientific literature, AICR/WCRF weighed the strength of the evidence linking these factors to lower risk for several cancers.

Diets high in: CONVINCINGLY lower risk of the following cancers:Foods containing dietary fiber ColorectumDiets high in: PROBABLY lower risk of the following cancers:Fruits Mouth, Pharynx, Larynx, Lung

Open Areas of Investigation: Laboratory ResearchLaboratory research is extensive on the group of compounds in cherries called anthocyanins. In laboratory studies, anthocyanins inhibit the growth of cancer cells and stimulate their self-destruction, without affecting healthy cells. These compounds also show anti-inflammatory and strong antioxidant effects. Lab studies on dietary fiber suggest it reduces cells’ exposure to cancer-causing substances. Healthful gut bacteria use dietary fiber to produce short-chain fatty acids that protect colon cells.

In comparison, there are relatively few studies on the cancer effects of the phytochemical perillyl alcohol. Limited studies suggest that perillyl alcohol acts as an antioxidant and stimulates self-destruction of abnormal cells. It also may inhibit cancer growth in animals, at least in part by inhibiting the process of angiogenesis, the formation of new blood vessels that tumors rely on to spread.

What's in Coffee? What you get in your cup of coffee varies with how the beans are grown and how you prepare it. Overall, coffee is a good source of the B vitamin riboflavin, and is also a concentrated source of antioxidant phytochemicals.

Coffee contains:

• Chlorogenic acid, an antioxidant compound that is the major phenol in coffee• Quinic acid, a phytochemical that contributes to the acidic taste of coffee• Cafestol and kahweol, compounds that are extracted from the beans' oil during brewing. Unfiltered coffee, such

as French press or boiled coffee, contains these compounds• Caffeine, a naturally occurring stimulant that affects the central nervous system• N-methylpyridinium (NMB), created by roasting, may make the antioxidants more potent

Chlorogenic acid may be slightly lower in decaf coffee according to limited research, but it still contains plenty of phytochemicals. Lab studies suggest that instant may be lower in antioxidant potency than brewed coffee, though more research is needed.

What Current Evidence Shows: AICR/WCRF Expert Report and Its Updates (CUP)Coffee, brewed from the beans of a small shrub or tree, contains vitamin B2 (riboflavin) and a variety of phytochemicals. After a systematic review of the global scientific literature, AICR/WCRF weighed the strength of the evidence linking coffee to lower or no risk for several cancers.

Diets high in: PROBABLY lower risk of the following cancers:Coffee Endometrial, Liver Substantial effect on risk UNLIKELY* Pancreatic, KidneyThere are several hypotheses on how coffee may possibly decrease cancer risk. Coffee is a major source of antioxidants. Limited small intervention studies suggest that coffee may improve markers of antioxidant status and reduce markers of inflammation in the short-term. Animal studies and human studies both suggest that regular and decaffeinated coffee may decrease insulin resistance, a condition that leads to high insulin levels in the body. Reducing insulin resistance could help reduce risk of cancers whose growth is promoted by excess insulin.

The Cancer ResearchOne serving of cranberries provides at least 10 percent of the recommended daily amount of fiber. Dietary fiber can act in several ways to lower cancer risk, including helping with weight control. (Excess body fat increases the risk of eleven different cancers, and dietary fiber can increase the feeling of fullness.)

CranberriesCranberries grow in northern bogs on low-lying vines, just above water. These bright red gems are native to North America and at one time whalers and mariners carried cranberries on their ships to prevent scurvy. Today you've probably heard claims that cranberry juice helps prevent urinary tract infections; though it appears to help some women, it is not a treatment. We do know that with their healthful nutrients and phytochemicals along with the rich color and flavor, cranberries make a great addition to any meal, not just at Thanksgiving.

Open Areas of Investigation: Laboratory ResearchLaboratory research is abundant on vitamin C and many compounds in cranberries, such as flavonoids.

Vitamin C protects cells' DNA by trapping free radicals and inhibiting the formation of carcinogens.In cell studies, cranberry extract and anthocyanins decrease free radical damage to DNA that can lead to cancer. They decrease growth and stimulate mouth, breast, colon, prostate, lung and other cancer cells to self-destruct. Cranberries' proanthocyanidins and ursolic acid also decrease growth and increase self-destruction of several types of cancer in cell studies. Research suggests that these compounds seem to work synergistically, providing more protection together rather than individually.In limited animal studies, those fed cranberries developed fewer and smaller cancers of several types when compared to animals not consuming cranberries. Cranberries also reduced inflammation and cancers' ability to invade other tissues. (Chronic inflammation increases the risk of several types of cancer.)

Diets high in: CONVINCINGLY lower risk of the following cancers:Foods containing dietary fiber ColorectumDiets high in: PROBABLY lower risk of the following cancers:Fruits Mouth, Pharynx, Larynx, Lung

AICR'S FOODS THAT FIGHT CANCERDark Green Leafy VegetablesSpinach, kale, romaine lettuce, leaf lettuce, mustard greens, collard greens, chicory and Swiss chard all have some fiber, folate and a wide range of carotenoids such as lutein and zeaxanthin, along with saponins and flavonoids.

According to AICR's second expert report, Food, Nutrition, Physical Activity, and the Prevention of Cancer: A Global Perspective, foods containing carotenoids probably protect against cancers of the mouth, pharynx and larynx.

Researchers believe that carotenoids seem to prevent cancer by acting as antioxidants – that is, scouring potentially dangerous “free radicals” from the body before they can do harm. Some laboratory research has found that the carotenoids in dark green leafy vegetables can inhibit the growth of certain types of breast cancer cells, skin cancer cells, lung cancer and stomach cancer.

What's in Beans and Peas?Dry beans and peas are rich in fiber (20% of Daily Value) and a good source of protein (10% of Daily Value). They are also an excellent source of folate, a B vitamin.

Pulses contain other health-promoting substances that may also protect against cancer:• Lignans and saponins• Resistant starch, starch not digested in the small intestine, is used by healthful bacteria in the colon

to produce short-chain fatty acids, which seem to protect colon cells.• Antioxidants from a variety of phytochemicals, including triterpenoids, flavonoids, inositol, protease

inhibitors and sterols.

The Cancer ResearchThere are several ways in which legumes may act to prevent cancer.

A serving of legumes provide at least 20 percent of the recommended daily amount of folate and fiber. Dietary fiber can act in several ways to lower cancer risk, including helping with weight control. (Excess body fat increases the risk of eight cancers.) Gut bacteria feed on fiber, which produces compounds that may protect colon cells. And folate is essential for healthy DNA and maintaining control of cell growth. Dry beans, split peas and other legumes also contain a variety of phytochemicals that scientists are studying for their anti-cancer effects.What Current Evidence Shows: AICR/WCRF Expert Report and its Updates (CUP)Dry beans and other legumes contain dietary fiber. After a systematic review of the global scientific literature, AICR/WCRF weighed the strength of the evidence linking this factors to lower risk for colorectal cancer.

Open Areas of Investigation: Laboratory ResearchIn laboratory studies, flavonoids found in legumes have slowed the development of cancers during several stages of development. Current research suggests that protection may come as much from directly affecting cell growth as from antioxidant activity. Lab studies suggest many phytochemicals in legumes may decrease growth factors and chronic inflammation, risk factors for many cancers, and increase self-destruction of cancerous cells. Animal and human studies show that healthful bacteria in the colon use fiber (resistant starch) in legumes to produce substances that seem to protect colon cells.

What's in Flaxseed?Flaxseed is an excellent source of magnesium, manganese and thiamin, and fiber; a good source of selenium; and provides protein and copper, too.

• Lignans: flaxseed is a particularly rich source of these plant estrogens• Dietary fiber: One serving, about 4 tablespoons of ground flaxseed, contains more than 7

grams of fiber.• Alpha-linolenic acid (ALA): about half of the fat in flaxseed is this plant form of omega-3

fat.• Gamma-tocopherol: a form of vitamin E

Flaxseed oil provides alpha-linolenic acid and both alpha- and gamma-tocopherol, two forms of vitamin E. It is not a source of fiber, selenium or the other nutrients noted above. It does not naturally contain lignans, though some brands contain added lignans.

The Cancer ResearchThe link between flaxseed and/or lignan to cancer risk is relatively well-studied. Most research has focused on flaxseed’s effects on breast cancer. Emerging areas of study include its impact on cancers of the prostate and colon.

What Current Evidence Shows: AICR/WCRF Expert Report and its Updates (CUP)Flaxseed is high in dietary fiber. After a systematic review of the global scientific literature, AICR/WCRF weighed the strength of the evidence linking these factors to lower risk for several cancers.

Diets high in: CONVINCINGLY lower risk of the following cancers:Foods containing dietary fiber ColorectumOpen Areas of Investigation: Laboratory ResearchIn animals, flaxseed, lignans and flaxseed oil decrease several different growth factors, and they slow tumor growth and the ability to spread both estrogen receptor-positive (ER+) and -negative (ER-) breast cancer. In limited animal studies, flaxseed does not interfere with actions of tamoxifen or trastuzumab (medications used for breast cancer treatment) and may even enhance their effectiveness.

In other animal studies, flaxseed and its oil decrease markers of inflammation, decrease number and size of colon cancer tumors, and inhibit growth and spread of prostate cancer.

The Cancer ResearchGarlic’s anti-cancer activity appears to stem from its allyl sulfur compounds and phytochemicals common to the allium family, which also include onions and scallions. Technically, garlic is a root vegetable but it is usually used for flavoring. Most of the research related to garlic and cancers have focused on colorectal and stomach. Yet emerging research suggests garlic may also play a role in the prevention of other cancers.

Open Areas of Investigation: Laboratory ResearchThe majority of laboratory research around garlic and cancers focuses on the effects of garlic’s allyl sulfur compounds, both the ones soluble in water and oil. One of the most well studied of these oil soluble compounds is allicin, which forms when the garlic tissue is damaged or crushed. The allicin quickly converts into several sulfur-containing compounds.

Cell and animal studies have found that garlic’s allyl sulfur compounds may play a role in cancer prevention by several mechanisms, including:

inhibiting enzymes that activate carcinogens, potentially cancer-causing compoundsboosting enzymes that detoxify carcinogenshelping with DNA repairslowing growth and stimulating self-destruction of cancer cells without disturbing normal cellslimiting cancer’s ability to spread by decreasing tumor’s ability to grow new blood vessels

Garlic’s allyl sulfur compounds – both the water and oil-soluble – also seem to prevent cancer by turning on tumor suppression genes.

What's in Garlic?Researchers are studying a variety of substances in garlic for their potential health benefits and anti-cancer activity. Garlic contain allyl compounds that are responsible for its odor and flavor. Because the serving size of garlic is just 1 teaspoon, the amount of nutrients and compounds per serving is small.

• Allicin: a bioactive compound released when garlic is crushed or chopped. Allicin forms several oil soluble allyl sulfur compounds; research has focused on a few of these compounds for potential health benefits. These benefits may include decreasing inflammation and possessing antimicrobial properties.

• S-allyl cysteine: A water-soluble allyl sulfur compound found in high doses in aged garlic extract.• Flavonoids, especially kaempferol and quercetin: compounds well studied for their anti-cancer properties.• Inulin: A plant storage carbohydrate that stimulates growth of beneficial bacteria in the colon, helping to protect against pathogens, toxins and carcinogens.• Saponins: Compounds studied for anti-tumor activity.

Grapes and Grape JuiceBoth grapes and grape juice are rich sources of resveratrol, a phytochemical well studied for anti-cancer effects.

The skin of the grape contains the most resveratrol. Resveratrol is in red, purple and green grapes, the amount depends much more on growing conditions than on color or type of grape.

Red wine also contains resveratrol. However, with AICR’s research reports finding that alcohol is associated with increased risk for cancers of the mouth, pharynx and larynx, esophagus, breast and colon and rectum (in men), wine is not a recommended source of resveratrol.

Studies suggest that polyphenols in general and resveratrol, in particular, possess potent antioxidant and anti-inflammatory properties. In laboratory studies, resveratrol prevented the kind of damage known to trigger the cancer process in cell, tissue and animal models.

Other laboratory research points to resveratrol’s ability to slow the growth of cancer cells and inhibit the formation of tumors in lymph, liver, stomach and breast cells. Resveratrol has also triggered the death of leukemic and colon cancer tumors.

In one series of studies, resveratrol blocked the development of skin, breast and leukemia cancers at all three stages of the disease (initiation, promotion and progression).

The Cancer ResearchSoy foods contain several key nutrients and phytochemicals studied for their cancer prevention properties. Many soy foods also contain dietary fiber, which links to lower risk of colorectal cancer. Soy foods contain isoflavones, which are phytoestrogens that in some ways mimic the action of estrogen. Because high levels of estrogen link to increased breast cancer risk, there was a fear that soy foods – and its isoflavones – may increase risk. Yet overall, human studies show soy foods do not increase risk and in some cases, research suggests they may lower it.Open Areas of Investigation: Laboratory ResearchThe majority of laboratory research involving soy and cancer risk has involved soy’s isoflavones genistein and daidzein.

In cell and animal studies, genistein, daidzein and other soy compounds have slowed cancer cell growth and prevented tumor formation. In lab studies, soy and genistein have decreased tumor growth and increase self-destruction of prostate cancer. Soy and its phytochemicals appear to prevent cancer development by reducing inflammation, and inhibiting activation of proteins that promote cell growth.

Open Areas of Investigation: Human StudiesIn general, Americans do not eat large amounts of soy, which makes it challenging for US observational studies to compare how highest versus lowest intake links to cancer risk. The majority of population studies involving soy are conducted in Asia, where soy is a dietary staple. Even so, across populations, studies now point to soy possibly protecting against some cancers and overall, presenting no increased risk.

Population studies link soy consumption with lower breast cancer risk in Asia, where women consume moderate amounts of soy throughout their life. A moderate amount is approximately one to two servings a day. Research now suggests that hormone-related protective effect of soy against breast cancer relates to soy consumption in childhood, adolescence, and throughout puberty. Soy also may affect cancer risk in some populations more than others, due to differences in genetics and gut bacteria that metabolize soy compounds into their active form.What about cancer survivors?Breast Cancer Survivors: Overall, the seven recent epidemiologic studies examining soy consumption among breast cancer survivors – in six population studies and one combined analyis – show that consuming moderate amounts of soy foods does not increase a woman’s risk for poorer outcomes. The amounts classified as moderate are comparable to what Asian women consume. Some of the studies point to a potential benefit among women receiving certain treatments or with certain tumor characteristics.

Among Asians, postmenopausal women who ate the most soy foods – about two to three servings a day –had the lowest risk of recurrence or death compared to women who ate the least, less than a few serving a week. These findings were also seen in studies among predominantly Caucasian women who consumed soy at levels comparable to the average Asian.

In the largest study to date, a pooled analysis of studies that included almost 10,000 breast cancer patients, consuming at least 10 milligrams isoflavones (mg) daily linked to a 25 percent decrease in breast cancer recurrence. This effect was seen among both women from the United States and Asia, and was most evident in survivors of ER-negative cancer and those with ER-positive cancer taking tamoxifen.

The Cancer ResearchMany of the phytochemicals and nutrients in winter squash are well studied in the laboratory. Winter squash also contain dietary fiber, which can act in several ways to lower cancer risk, including helping with weight control. Excess body fat increases the risk of seven different cancers, and dietary fiber can increase the feeling of fullness.

What's in Winter Squash?

Winter squash are excellent sources of vitamin A, good sources of vitamin C and dietary fiber. They are also a good way to get potassium.

Winter squash, including pumpkins, are rich in carotenoids, including:

• beta-carotene and alpha-carotene: these carotenoids can act as antioxidants. Also, our bodies convert these to vitamin A, a nutrient important for immune function and maintaining healthy cells among other roles.

• lutein and zeaxanthin: these yellow pigmented carotenoids help protect eye health by filtering high-energy ultraviolet rays that can damage our eyes’ lens and retina. They act as antioxidants here and possibly elsewhere in our bodies.

Open Areas of Investigation: Human StudiesHuman studies related to winter squash and cancer risk compare groups of people who consume relatively high and low amounts of total vegetables, squash, and/or levels of carotenoids.Further research is underway in all the noted areas.• Population studies that compare people with high and low amounts of beta-carotene in their diet or their blood link beta-carotene with lower risk

of esophageal cancer.• Both beta-carotene and lutein consumption are related to lower risk of renal cell cancer – a type of kidney cancer – in several large population

studies.• One study, which included almost 15,000 adults, found those with higher blood levels of alpha-carotene suffered fewer deaths from cancers of the

aerodigestive tract after almost 14 years. Aerodigestive cancers include cancers of the esophagus, stomach, colon, liver, and pancreas, and larynx.• Lab research shows that vitamin C protects cells’ DNA by trapping free radicals and inhibiting formation of carcinogens.• Alpha-carotene and beta-carotene are related carotenoids. Lab research shows that both act as antioxidants that also promote cell-to-cell communication, helping control cell growth.• Lutein and zeaxanthin are concentrated not only in our eyes, but also in skin. A recent animal study suggests that dietary intake may decrease development of skin cancer related to sun

exposure.• Lab research shows that dietary fiber reduces cells’ exposure to cancer-causing substances and gut bacteria use it to produce short-chain fatty acids that protect colon cells.

What's in Tomatoes?Tomatoes are an excellent source of vitamins C and A (produced from beta-carotene) and one serving provides at least 10 percent of the daily recommended potassium. In addition to beta-carotene, tomatoes contain a number of other carotenoids: • Lycopene, an antioxidant that gives tomatoes their red color. Red tomatoes, sauces and other tomato

products are by far our top source of lycopene • Phytoene and phytofluene, colorless carotenoids that are precursors of lycopene

The Cancer ResearchTomatoes’ cancer preventive potential comes from being a non-starchy vegetable as well as a source of vitamin C and carotenoids. The carotenoid lycopene is especially well studied for its cancer preventing properties, but results linking foods containing lycopene to lower cancer risk are currently inconsistent.

Open Areas of Investigation: Laboratory ResearchLaboratory studies mainly focus on investigating the link between tomatoes' carotenoids and lower cancer risk. The carotenoid lycopene, which has antioxidant properties, appears to prevent DNA and other cell damage. In cell studies, lycopene stimulates self-destruction and decreases growth and metastasis of several types of cancer cells.Open Areas of Investigation: Human StudiesOf the many human studies investigating tomatoes, lycopene and cancer risk, most are observational studies of populations. Studies of breast, colorectal and stomach cancer show a neutral or possibly protective effect. Research in healthy volunteers suggests that intake of tomatoes but not lycopene supplements can help protect DNA from damage. Early research linked tomato consumption and blood levels of lycopene to reduced prostate cancer risk, leading to a focus on the role of tomato consumption and this cancer.Large studies that have focused on tomatoes and lycopene include The National Cancer Institute's Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. This study compared men with prostate cancer to those without and found that blood levels of lycopene were unrelated to cancer risk. However, a 2014 Health Professionals Follow-up Study concluded that lycopene intake linked to reduced risk of prostate cancer, especially of the more advanced prostate tumors.

Challenges in the Research: Prostate cancer studies are difficult to interpret because this disease often takes decades to develop, with some tumor types aggressive and others slow growing and possibly not lethal. Studying prostate cancer is also challenging due to PSA, prostate-specific antigens, tests. PSAs are often used as a measure of prostate cancer risk but may also be elevated in non-cancerous prostate hyperplasia or inflammation of the prostate gland. Researchers are continuing to look for more specific indicators, including certain forms of PSA, which may provide more accurate information about overall and aggressive prostate tumor risk.

Impact of tomato consumption may vary depending on type and stage of this cancer, synergy with other foods and the proportion consumed as processed tomatoes, which are linked to greater increase in blood lycopene levels. .

Investigations of tomato and/or lycopene intake in prostate cancer patients are limited and results are mixed. Research is ongoing to determine the therapeutic potential, if any, of tomatoes or lycopene.

What's in Walnuts?

Walnuts contain high amounts of polyphenols, phytochemicals that have antioxidant properties. They also contain a broad range of other potentially protective compounds:• Elligitannins, which are broken down to ellagic acid• Gamma-tocopherol, one of several types of vitamin E compounds• Alpha-linolenic acid, an omega-3 fatty acid• Polyphenols including flavonoids and phenolic acids• Phytosterols, plant compounds known to help lower blood cholesterol that are under study for their

potential antioxidant and anti-inflammatory effects in the body.• Melatonin, a hormone and antioxidant

Walnuts are an excellent source of copper and manganese, and a good source of magnesium.The Cancer ResearchFor cancer risk, walnuts are the most studied among the nuts.There are a few dozen studies investigating cancer and whole walnuts, with many more on the compounds they contain. Walnut’s alpha-linolenic acid, ellagic acid and flavonoids are well studied in the laboratory.What Current Evidence Shows: AICR/WCRF expert report and its updates (CUP)AICR’s report and its continuous updates found the evidence currently too limited to draw any conclusions about walnuts – or any nuts – and cancer risk."Several animal studies show that including walnuts in the diet slows or prevents the growth of breast and prostate cancers. The addition of walnuts to your plate is a good cancer preventive measure.”- Lauri Byerley, PhD, LSU Health New OrleansOpen Areas of Investigation: Laboratory ResearchIn mice, several studies found that consuming walnuts resulted in decreased breast and colon tumor growth compared to the animals eating a standard diet. Limited studies in mice also show reduced growth of prostate cancer. One study indicated that consuming a walnut diet altered the expression of genes that regulate cell growth. Walnuts’ omega-3 fat, alpha-linolenic acid, seemed to account for some, but not all, of the protection seen.Cell and animal studies studies have also investigated gamma-tocopherol, one of the eight forms of vitamin E. Most studies on the fat-soluble types of vitamin E have focused on alpha-tocopherol, the form listed on nutrition labels and recognized as most important for our health. Yet several studies suggest that walnuts’ gamma-tocopherol has stronger anti-inflammatory and cancer-protective effects than alpha-tocopherol.Open Areas of Investigation: Human StudiesA couple of short-term studies suggest that eating walnuts can raise antioxidant levels in the body. One study also suggested it decreased signs of DNA damage. Yet one of the longer human studies involving 21 people found that their blood level of antioxidants were the same both before and after eating walnuts every day for six weeks.

Whole GrainsWhole grains are hearty, flavorful and filling. Choose from brown rice, oatmeal, corn, whole-wheat bread, barley, bulgur, kasha, millet, sorghum, farro and more. The fiber-rich bran, nutrient-packed germ and starchy endosperm are all natural parts that remain in whole grains. Refined grains lack the bran and germ, while whole grains provide more nutrition, fiber and health-promoting phytochemicals.The Cancer ResearchThe wide variety of whole grains makes it challenging to pinpoint how this food group reduces cancer risk, which it does. All whole grains contain fiber. There are several ways fiber may lower risk, including diluting potential carcinogens and promoting healthful bacteria growth. Whole grains may also help with weight control; excess body fat increases the risk of 11 cancers. Brown rice, oatmeal and other whole grains are also good sources of selenium, a mineral that has antioxidant properties.Each type of whole grain also contains a variety of phytochemicals, many being studied for their cancer protective effects.

Open Areas of Investigation: Human StudiesThere is a wide variety of whole grains, and the mixed results seen in population studies of whole grains’ effects on inflammation, insulin resistance and weight may reflect the varying fiber and nutrient content of different grains, different effects of intact cooked whole grains (such as oatmeal, brown rice and quinoa) compared to whole-grain products made from milled flours (such as bread and breakfast cereals), or differences in individual starting points regarding weight and health.Difficulties in accurately measuring how much whole grains people consume poses challenges to detect how whole grains may influence cancer risk. In recent years researchers have increasingly used blood levels of a compound called alkylresorcinol, which forms from compounds in whole grain wheat and rye, as a biomarker of whole grain consumption. This may lead to clearer answers as research progresses.Colorectal: AICR/WCRF's analysis of population studies links greater consumption of whole grains and foods high in dietary fiber to a decrease in colorectal cancer. risk For whole grains, each 90 grams (about 3 servings) of whole grains links to 17 percent lower risk of colorectal cancer. The protective link seen with whole grains was beyond what could be expected based on dietary fiber.Breast: Population studies on breast cancer related to dietary fiber and whole grains are more limited and mixed. One analysis of studies ties dietary fiber intake of 25 grams a day and more with lower risk, although this link may vary with the type of breast cancer and type and source of fiber.Other Cancers: Several population studies link whole grains with lower levels of inflammation and insulin resistance, which links to cancer development. Yet controlled intervention trials are not clear in showing these benefits.Weight Management: Excess body fat increases risk of 11 cancers. Short-term intervention trials, which typically last 3 months or less, have generally shown greater whole-grain consumption has no effect on weight or weight gain. But population studies consistently link greater whole grain consumption with lower body mass index (BMI) and less weight gain over about ten years. Several studies also suggest that consuming whole grains rather than refined grains causes a relatively modest but greater loss of body fat and abdominal fat, especially when whole grains are part of a reduced-calorie diet.

Can Cancer Be Prevented?Cancer can take years, or even decades to develop, yet many people believe that getting cancer is due to genes, fate or bad luck. But scientific research shows that our cancer risk depends on a combination of our genes, our lifestyle and our environment – things we can and cannot control. So, when we talk about cancer prevention, we focus on the areas we can control and how we can lower our risk. This is important: there are things you can do today that can help to prevent, delay, or even stop the cancer process at all stages of life.

Why Is Prevention Important?Prevention is more important than ever. In the U.S., 1 in 4 people will develop cancer at some point in their lives. A cancer diagnosis can be devastating for patients and their families. The physical and emotional distress may be a compelling enough reason to help individuals lower their cancer risk. But we also know that rates of cancer are increasing in the United States, which translates to a growing burden in terms of treatment and costs for care. By preventing cancer, the number of new cases will be lowered and reduce the burden that cancer places on the population.

How Many Cancers Could Be PreventedAround 40 percent of cancer cases are preventable, which means that 694,000 cases of cancer could be prevented in the U.S. every year by reducing our exposure to the cancer risk factors that we can control – including diet, weight and physical inactivity.

Lifestyle Risk Factors for CancerWhen we talk about risk factors we can control we often use the word “lifestyle.” AICR’s research shows that the choices you make about maintaining a healthy body weight, eating a healthy, balanced diet, and staying active can reduce your chances of developing cancer. Learn more.We can also reduce our risk by making choices about not smoking, enjoying the sun safely and avoiding certain infections. Learn more.

Assessing Your Cancer RiskAll of us are at some risk for developing cancer at some point in our lives. It’s difficult to know how much risk, exactly. Some smokers never get lung cancer whereas some healthy, non-smoking individuals do develop lung cancer. Similarly, there are people with obesity who never develop any of the 12 cancer linked to this condition while some lean individuals do.But for the vast majority of us, our cancer risk is something we can increase or decrease. And that’s what we mean, when we talk to individuals about cancer prevention. You can help protect yourself against cancer. And given that the science says, strongly and consistently, that healthy everyday choices can and do decrease cancer risk, it makes sense to make those choices.

There are no guarantees when it comes to cancer. But every time you decide to go for a run or choose a fresh salad over a fast-food burger, you’re playing the odds. And those odds are very good. Decades of research into the science of cancer prevention show that a healthy overall lifestyle is the smartest, safest bet you can make.