Linking the connection between obesity and prostate cancer

Two of the most common medical issues facing men today are obesity and prostate cancer.  When a man is both obese and has prostate cancer, it can be a dangerous combination. This was demonstrated by a 2015 study that showed prostate cancer patients had a greater than twofold association of prostate cancer recurrence when men were obese or had a high body mass index (BMI).  A more recent 2017 study in the International Journal of Cancer, found men diagnosed with localized prostate cancer showed a positive association between long-term weight gain and risk of lethal prostate cancer. This is attributed to metabolic changes associated with weight gain possibly promoting prostate cancer progression.

We know that obesity has many direct consequences on health and is associated with the onset of aggressive cancers, but the mechanisms underlying this phenomenon are not exactly known. With prostate cancer, research has shown there to be a connection between carrying excess weight and developing prostate cancer.

One of the best things a man can do at any age is to reach a healthier body weight. Among lifestyle factors for preventing prostate cancer, obesity is by far the strongest and clearest link to developing an aggressive form of prostate cancer and ultimately a deadly course for this disease.  Another factor having a correlation between obesity and prostate cancer is ethnicity.

The link between obesity and prostate cancer in black men

Black men have the highest rates of prostate cancer cases and the highest rates of prostate cancer deaths in the U.S. Understanding the reasons behind these disparities could influence behaviors that may help lower the risks.

A 2015 study by researchers in Seattle and published online in JAMA Oncology, found that obesity showed a significant increased risk of both low-grade (slow-growing) and high-grade (fast-growing) prostate cancer in black men. More than 3,000 black men and over 22,000 white men were selected to take part in the SELECT trial, a study which began in 2001 to find out whether selenium and vitamin E supplements could help prevent prostate cancer. During the follow-up period of about 5 years, 270 black men and 1,453 white men in the study developed prostate cancer.  Overall, the study found 58% increased risk for prostate cancer among black men when compared to white men. Black men who were obese had an even greater risk. 

Of the obese black men, men who with a BMI of 35 or greater, were more likely to develop prostate cancer, than those with a BMI below 25 (a normal body weight). Obesity among black men was linked to greater risk of both low-grade and high-grade prostate cancer.

The results showing that black men who were obese had a higher risk of prostate cancer, likely stems from social as well as biological factors. Obesity is influenced by a variety of factors, including genetic factors and environmental factors as opposed to a causal relationship between obesity and prostate cancer. 

Prostate cancer risk affected by a man’s height and weight

An interesting study from 2017 found that body size seems to have an impact on a man’s risk of developing prostate cancer. Researchers with the study reviewed data from over 100,000 men and found that for every ten centimeters in height, the risk of developing an aggressive prostate cancer increased by 21 percent. Some of the speculations of possible factors for this finding included that more body mass means more blood, which could dilute the results of a prostate specific antigen (PSA) test possibly leading to a biopsy being performed at a later time, when prostate cancer had had more time to grow. Another theory was men with more fat cells in the body, whether by being obese or tall, could have an impact on how aggressively prostate cancer grows, since fat cells make proteins that can influence cellular growth.

Diet and prostate cancer

While it is not possible to change your ethnicity or height, manipulating weight is another story. Reaching a healthy body weight does takes motivation and self-discipline but it can be done.  Men who develop healthy habits of eating a heart healthy diet will also be doing their prostate health a favor too.

New studies at Cedars-Sinai are being conducted to better understand how losing weight impacts the growth of prostate tumors. In one trial, prostate cancer patients were placed on a diet that was very low in sugar and carbohydrates, resulting in an average loss of 30 pounds in six months.

One of the main focuses of the study is encouraging patients to give up simple sugars found in sweetened beverages, cookies, candy, and other sweets. Sugary foods can lead to an excess of calories along with unhealthy fat leading to high levels of inflammation that is intertwined with obesity and prostate cancer.

Overall, a strong focus for all men should be to consume more heart healthy foods such as omega-3 rich fatty fish (salmon, mackerel, herring, tuna and trout), lean meat, poultry, low-fat dairy, whole grains, fruits and vegetables, and nuts.  Foods men should avoid include chips, pretzels, crackers, processed meats (bacon, sausage, hot dogs, corn dogs, corned beef, bologna, pepperoni, salami, chicken patties, and fish sticks), soda, French fries, burgers, and cheese.

Reaching and maintaining a normal body mass index is achievable by exercising regularly, not over-eating and choosing healthy foods 90% of the time.  Other important lifestyle changes which can impact weight include reducing stress and getting sufficient sleep.  Even if a man who is following this way of living does receive a prostate cancer diagnosis, he will be in a better position of surviving it.

In the meantime, healthy lifestyle changes, talking with their healthcare provider, undergoing regular prostate cancer screening, and knowing risk factors for developing prostate cancer, will be a man’s best bet for beating the odds of a prostate cancer diagnosis.