Prostate cancer affects roughly one in six men throughout their lifetime. The good news is that healthy dietary habits can potentially boost prostate health.
This article offers diet tips that can help prevent prostate cancer, including eating low-fat foods, consuming at least 25 grams of fiber daily, eating at least five servings of fruits and vegetables a day, and limiting the amount of simple sugars.
This article also discusses prostate cancer, including symptoms related to the disease and potential risk factors.
Keep in mind that this article is not intended as medical advice. If you have prostate cancer or believe you’re at risk for prostate cancer, seek help from your doctor or health care provider.
The prostate is a walnut-sized gland located behind the base of a man’s penis, in front of the rectum, and below the bladder – it surrounds the urethra, the tube-like channel that carries urine and semen through the penis, said Eva A. Meyers, Ph.D., Oncology Nurse Practitioner at the Cecilia Gonzalez De La Hoya Cancer Center at Adventist Health White Memorial.
“The prostate’s main function is to make seminal fluid, the liquid in semen that protects, supports, and helps transport sperm,” Meyers explained. “Cancer begins when healthy cells in the prostate change and grow out of control, forming a tumor. A tumor can be cancerous or benign. A cancerous tumor is malignant, meaning it can grow and spread to other parts of the body. A benign tumor means the tumor can grow but will not spread.”
Prostate cancer is when healthy cells in the prostate develop errors in their DNA and cannot repair themselves, added Socorro Carranza, an outpatient registered dietitian at Dignity Health.
“Healthy cells without errors can grow and divide at a normal rate and work and function normally,” Carranza said. “However, in damaged cells that become cancerous, the cells continue to divide uncontrollably and form a tumor.”
Prostate cancer is the most common cancer among men, except for skin cancer, said Meyers, adding that this year, an estimated 174,650 men in the United States will be diagnosed with prostate cancer.
“Approximately 80% of cases are diagnosed in men over age 65,” Meyers noted. “The average age of diagnosis is age 66; the disease rarely occurs before age 40. For unknown reasons, the risk of prostate cancer is about 60% higher in black men than in white men.”
More encouragingly, long-term survival with prostate cancer is increasing overall likely due to the fact that there is relatively early detection of this disease process and there are multiple means of treating this disease, according to Dr. Kamyar Ebrahimi, a fellowship-trained urologist in the field of robotic surgery at Adventist Health Glendale in Southern California.
Often, early-stage prostate cancer has no symptoms or sign, according to Meyers. It is usually found through a PSA (prostate-specific antigen) blood test; or a DRE (digital rectal exam).
Later stage prostate cancer may cause symptoms or signs such as:
- Frequent urination
- Weak or interrupted urine flow
- The urge to urinate frequently at night
- Blood in the urine or seminal fluid
- New onset of erectile dysfunction
- Pain or burning during urination
- Discomfort or pain when sitting
“These symptoms are also frequent for non-cancerous prostate conditions, so further evaluation is needed by your medical provider,” Meyers said.
According to Meyers, risk factors for prostate cancer include the following:
Age: Your risk increases after age 50.
Race/ ethnicity: Black men have a higher risk than white men.
Family history: Prostate cancer that runs in the family, called familial prostate cancer, occurs about 20% of the time. Hereditary prostate cancer means a gene mutation was inherited from a relative, accounts for about 5% of all cases. The other 75% have no contributory cause.
Agent Orange exposure: This causal relationship is listed by the U.S. Department of Veterans Affairs as a chemical used during the Vietnam War.
Eating habits: Obesity has an associated cause, and a healthy diet is recommended to reduce risk for all cancers.
A risk factor is anything that increases a person’s chance of developing cancer, Meyers added. Although risk factors often influence the chance to develop cancer, most do not directly or by themselves cause cancer.
“Some people with several known risk factors never develop cancer, while others with no known risk factors do,” Meyers said. “Knowing your risk factors and talking about them with your doctor may help you make more informed lifestyle and health care choices.”
When Dr. Ebrahimi counsels patients about prostate cancer and its prevention, “I try to emphasize the importance of a heart-healthy diet,” he noted, adding that in general, that means a diet which is mostly based on plants.
“Eating five servings of fruits and vegetables is a key,” advised Dr. Ebrahimi, who recommends eating all colors of fruits and vegetables to obtain the necessary nutrients and vitamins to avoid relying on supplements.
A Mediterranean diet can also help reduce the risk of prostate cancer, according to Teresa Baczkowski, manager of Clinical Nutrition at the Cecilia Gonzalez De La Hoya Cancer Center at Adventist Health White Memorial.
A Mediterranean diet includes the following:
- Olive, grapeseed or avocado oils
- Cruciferous vegetables (cabbage, broccoli, chard and similar vegetables)
- Dark fruits like pomegranates and dark-colored berries
- Tomato-based dishes
Additionally, “flax seeds, pumpkin seeds, nuts, garlic, and soy foods are also good in a healthy diet,” Baczkowski said.
Dr. Ebrahimi recommends increasing fish and poultry intake in lieu of red meats. For instance, salmon, herring, mackerel, and anchovy, which contain high amounts of omega-3 fatty acids, are a very tasty and easy way to incorporate this beneficial component in the diet, and “can also increase the amount of good cholesterol in patients which has been shown to correlate with prostate health.”
According to Carranza, foods that can potentially help prevent cancer from forming include those high in vitamin C and vitamin E:
- Bell peppers
- Sweet potato
- Brussels sprouts
According to the American Cancer Society, several studies suggest that diets high in certain vegetables – including tomatoes, broccoli, cauliflower, and cabbage – or fish may be linked with a lower risk of prostate cancer, especially more advanced cancers.
Having a well-balanced diet that’s low in saturated fat and managing weight can definitely help a man reduce his risk of getting prostate cancer, according to Carranza, who noted that population studies show a strong link between diet and the development of prostate cancer.
For example, in the last 20 years since American fast foods have been introduced in Japan, obesity has increased from 5% to 20% – and the incidence of prostate cancer has also increased.
“In addition, it has been noted that when people from countries with low incidence of prostate cancer, like China, move to the U.S., their risk of developing prostate cancer increases,” Carranza noted.
Fortunately, men can help protect themselves against prostate cancer by increasing their intake of fresh fruits and vegetables.
“When people increase their intake of fresh fruits and vegetables they increase their intake of fiber and cancer-fighting micronutrients such as phytonutrients and antioxidants,” Carranza explained. “Phytonutrients and antioxidants help the body fight against and prevent the process that causes damage to the DNA, and thus help prevent cancer from forming.”
A study on nutrition and prostate cancer conducted by UC San Francisco Medical Center indicated that “good nutrition may reduce the incidence of prostate cancer and help reduce the risk of prostate cancer progression.” Additionally, “there are many studies currently being conducted to further understand how diet and prostate cancer are related.”
The study offered the following guidelines for a healthy diet that can help boost prostate health:
1. Consume at Least Five Servings of Fruits and Vegetables Daily
They contain vitamins, minerals, and fiber as well as various cancer-fighting phytochemicals, such as carotenoids, lycopene, indoles, and flavonols.
There is consistent evidence that diets high in fruits and vegetables are associated with decreased risks of many cancers. While results for prostate cancer risk are not yet conclusive, they are promising.
Men who consumed at least 28 servings of vegetables per week had a reduced risk of prostate cancer compared with those who ate fewer than 14 servings per week.
There is some evidence that vegetables — particularly cruciferous vegetables like broccoli, cauliflower, cabbage, kale, Brussels sprouts, and bok choy — may be associated with a reduced risk of prostate cancer.
Men who ate three or more servings of cruciferous vegetables per week had a 41 percent decreased risk of prostate cancer compared with men who ate less than one serving per week.
The benefit of fruits and vegetables in regards to cancer protection may be related to high amounts of carotenoids in certain fruits and vegetables, according to some key population studies.
One study indicated that fructose, or fruit sugar, resulted in a lower risk of prostate cancer.
What to Do: Consume at least five, preferably eight to 10, servings of fruits and vegetables daily for their cancer-protective effects. One serving equates to:
- 1/2 cup fruit or vegetable
- 1 cup raw leafy greens
- 1/4 cup dried fruit or vegetable
- 6 fluid ounces of fruit or vegetable juice
2. Consume 25 to 35 Grams of Fiber Daily
A plant-based diet is naturally high in fiber, which has a number of benefits:
Fiber may bind to toxic compounds and carcinogens, which are then later eliminated from the body.
A high-fiber diet works to reduce hormone levels that may be involved in the progression of prostate cancer.
One study indicated that a high-fiber, low-fat diet followed only for 10 days resulted in serum changes that reduced the growth of prostate cancer.
Prostate cancer mortality is inversely associated with consumption of cereals and nuts or seeds, according to a study in the Journal of the National Cancer Institute.
A diet rich in natural fiber obtained from fruits, vegetables, legumes and whole grains such as whole-grain cereals and bread may reduce cancer risk and reduce the risk of prostate cancer progression.
What to Do: Aim for 25 to 35 grams of fiber daily. To get more fiber, choose bread with three or more grams of fiber per slice. The first ingredient on the label should be whole or sprouted grain flour, not white flour or unbleached white flour. Also, include whole grains — such as oats, barley, quinoa, amaranth, bulgur, and millet — in your diet.
For more ideas on how to get more fiber, see Increasing Fiber Intake.
3. Eat a Low-Fat Diet
The increased cancer risk observed in developed countries may be, in part, due to the fact that a high-fat diet stimulates increased testosterone levels, which is known to be associated with prostate cancer growth.
A comprehensive review reported that 24 of 32 studies found positive, although not all statistically significant, associations between dietary fat intake and prostate cancer risk.
Prospective studies to date, however, have failed to find a consistent association between prostate cancer and overall fat intake.
Aim for 20 percent of your total calories from fat, with less than 10 percent of total calories from saturated fat.
The type of fat is significant. According to research conducted by UC San Francisco Medical Center, several studies indicate a positive association between saturated fat intake from meat and dairy products and prostate cancer.
Intakes of red meat and dairy products appear also to be related to increased risk of metastatic prostate cancer. Therefore, it is wise to reduce or eliminate consumption of red meat, milk and other dairy products.
What to Do: Reduce or eliminate consumption of red meat, milk and other dairy products. Limit the use of butter, mayonnaise, baked goods and regular salad dressing due to their high saturated fat and total fat content. Consider rice vinegar, balsamic vinegar, lemon juice or salsa as alternative salad dressings. Limit cheese consumption. Cheese is typically between 60 to 80 percent fat, much of which is saturated fat.
4. Eat Omega-3 Fatty Acids
Omega-3 fatty acids may reduce your risks for prostate cancer and cancer progression. They induce apoptosis (cell death), suppress cancer cell initiation and compete with arachidonic acid, which limits harm from arachidonic acid. One study indicated that men who consumed cold-water fish three to four times per week had a reduced risk of prostate cancer.
A more recent study found similar results. Men who consumed fish three or more times per week also had a lower risk of prostate cancer, especially for metastatic prostate cancer where the effect was even greater.
Researchers in New Zealand reported that men with high levels of EPA and DHA, the omega-3 fats found in fish, had a 40 percent lower risk of prostate cancer than those with low blood levels.
A 30-year follow-up study found that men who ate no fish had a two to three times higher frequency of prostate cancer than those who ate moderate or high amounts of fish. The mechanism of cancer reduction may occur through the inhibition of arachidonic acid-derived eicosanoid biosynthesis.
Dietary sources of omega-3 fatty acids include coldwater fish — such as salmon, trout, herring and sardines — flaxseeds, walnuts, soybeans, and canola oil.
What to Do: Consume fish at least twice weekly to obtain an adequate amount of omega-3 fatty acids.
» For Further Reading: Guide to Omega-3 Supplements: Uses, Health Benefits & Side Effects
5. Consume Nuts
Nuts are highly concentrated in monounsaturated fatty acids, which are neutral in terms of stimulating cancer growth and may be beneficial for heart disease. They are, however, high in fat.
What to Do: Minimize consumption of nuts due to their high-fat content. This includes peanuts, macadamia nuts, and pistachios.
6. Limit Simple Sugars
High-sugar foods are usually:
- Highly processed and refined
- Low in nutrient value
- Low in fiber
Furthermore, these foods appear to increase serum insulin and serum IGF-I levels, which may stimulate cancer cell growth.
What to Do: Simple sugars should be consumed in limited amounts. Avoid sweets such as candy, cookies, cakes, and pies. Limit your intake of products made with refined flours.
7. Drink Plenty of Water
- Carries nutrients and waste products
- Participates in chemical reactions
- Acts as a lubricant and cushion around joints
- Acts as a shock absorber in the eyes and spinal cord
- Aids in the body's temperature regulation
- Maintains blood volume
In addition, the body needs more fluid when eating a high-fiber diet.
What to Do: Drink plenty of water daily to help meet fluid needs. Note that caffeine acts as a diuretic, increasing water loss. Your fluid needs increase with high consumption of caffeinated beverages.
8. Avoid Consuming Too Many Calories
Some evidence indicates that a high caloric intake increases one's risk of various cancers, including prostate cancer.
A case-control study reported a 115 percent increase risk in local prostate cancer and a 96 percent increase risk in regional/distant prostate cancer for those consuming higher calorie diets (2,439 or more calories a day) compared with individuals consuming a lower calorie diet (less than 1,322 calories a day).
In a separate study, researchers reported a nearly four-fold increase in prostate cancer risk in men who consumed the most calories (more than 2,624 calories a day) compared with men who consumed the least calories (1,064 calories a day).
An earlier study found that caloric intake was positively associated with preclinical prostate cancer risk; as caloric intake increased, cancer risk rose significantly.
The greatest risk was for subjects who consumed more than 3,475 calories a day. All of this suggests that the mechanism involved may be related to the decrease in IGF-I observed when caloric intake is restricted.
To help boost prostate health, Carranza recommends avoiding or reducing the following:
- Fast food
- Red meat
- Butter or margarine
- Processed baked goods
- Processed snack foods
Additionally, “completely avoid trans fat in foods,” Carranza advised. “When looking at the ingredients in a product, make sure you do not see hydrogenated oil.”
Trans fatty acids are known to be atherogenic, or heart disease-causing, according to the study on nutrition and prostate cancer conducted by UC San Francisco Medical Center.
They also may cause an imbalance in hormonal systems that regulate healing, lead to the construction of defective membranes and encourage the development of cancer.
Limit the use of hydrogenated fats found in products such as margarine, fried foods and processed foods, which are high in harmful trans fatty acids. When you read that a product contains "hydrogenated" or "partially-hydrogenated" oils, you may want to consider putting it back on the shelf.
Omega-6 fatty acids, which is linoleic acid that can be converted to arachidonic acid, may stimulate the growth of prostate cancer cells, according to a study on nutrition and prostate cancer conducted by UC San Francisco Medical Center. These fatty acids are found in corn oil, safflower oil, sunflower oil, cottonseed oil, soybean oil, and other polyunsaturated oils.
Substitute olive oil for your current cooking oil, but remember to use in moderation. These oils are rich in monounsaturated fats, which have not been shown to increase cancer risk.
Prostate cancer incidence and mortality rates are decreasing or stabilizing in most parts of the world, with the United States recording the biggest drop in incidence, according to results presented at the American Association for Cancer Research Annual Meeting in April 2019.
“Despite the trend toward declining rates, prostate cancer remains the second most commonly diagnosed cancer and the sixth leading cause of cancer death among men worldwide,” Meyers said. “The reason for declining rates is largely due to increased use of PSA screening and population awareness and access to preventive healthcare.”
Adequate exercise, regular medical checkups and screenings, eating a variety of fruits and vegetables, avoiding nitrates in food and avoiding high-temperature cooking of red meats, can potentially help prevent prostate cancer, Baczkowski said.
Additionally, “sunshine and a healthy lifestyle are all important for cancer prevention,” Baczkowski added. “Avoid all forms of fad diets and limitations in diets that result in extreme weight gain or loss are detrimental. This will depress your immune system which is our body’s protection that keeps us healthy.”
» Recommended Reading:
- Cancer Prevention Diet: 7 Foods That Can Lower the Risk of Cancer
- Natural Ways That Help Reduce the Risk of Prostate Cancer
- Best Grains, Fruits, and Vegetables That Improve Digestion