Prostate Cancer: Men - you need to monitor your dairy intake

Calcium is a multi-tasker. It lowers colorectal cancer risk, strengthens bones, supports heart and muscle health, stimulates digestive enzymes, and can even help make weight-loss diets more effective.

But recent research suggests that very high levels of dietary calcium intake - particularly from dairy products - may increase the risk of one of the most common forms of cancer.

Milky way
Last month, researchers at the Fox Chase Cancer Centre in Philadelphia (US) published the results of a study that examined the association between calcium and dairy product intake and the increased risk of prostate cancer.

Using data from the first National Health and Nutrition Examination Epidemiologic Follow-Up Study, nearly 10 years of medical records were collected on more than 3,600 men. All of the men had completed dietary questionnaires in the early 80s.

The Fox Chase team identified 131 cases of prostate cancer. After adjusting for age, race, smoking and other factors, they produced the following conclusions:

 Men who reported the highest dairy product intake were 2.2 times more likely to develop prostate cancer compared to men who had the lowest intake

 Similarly, men who had the highest intake of dietary calcium were also 2.2 times more likely to develop prostate cancer

 Men who reported the highest intake of low-fat milk were 1.5 times more likely to develop prostate cancer compared to men who had the lowest intake, but whole milk intake was NOT found to be linked to increased risk 

Neither vitamin D nor phosphorous was linked with increased prostate cancer risk

Know your risk
So...what gives? Low-fat milk raises risk, but whole milk doesnt, in spite of the fact that high dairy intake does raise risk? In their conclusions, published in the American Journal of Clinical Nutrition, the researchers write: The mechanisms by which dairy and calcium might increase prostate cancer risk should be clarified and confirmed. I would say thats putting it mildly.

Ill be keeping an eye out for further studies that examine the dairy intake/prostate cancer association. Obviously, something important seems to be going on here, but were a long way from sorting out the specifics.

In the meantime, men and their doctors should at least make note of this potential risk factor for prostate cancer. And thats especially true for men who are already in high-risk groups. Here are some of the primary risk factors as cited by Cancer Research UK:

 Prostate cancer risk rises after the age of 50; men over the age of 65 account for more than 70 percent of all prostate cancer cases

 Risk more than doubles in men whose father or brothers have prostate cancer

 Risk is considerably higher if several relatives also have prostate cancer, or if a relative was young when diagnosed

 Prostate cancer is more common in men of African descent

Risk is also believed to be higher in men whose diets include large amounts of red meat, especially if their diets do not include adequate amounts of fruits and vegetables

The old standbys
As long as were on the topic of prostate cancer risk, Ill quickly review two nutrients that may significantly reduce that risk: vitamin E and selenium.

In a trial in Finland, 300 middle-aged men who took a vitamin E supplement for more than five years reduced their prostate cancer risk by almost a third, compared to men who didnt supplement with the vitamin. And risk dropped even further for those who also ate foods rich in vitamin E (including almonds, spinach, mustard greens, green and red peppers and sunflower seeds).

A study at Stanford University in the US demonstrated that men with low blood levels of selenium may be four to five times more likely to develop prostate cancer than men with normal levels of the mineral.

The study also confirmed that selenium levels decrease as men age - mirroring the fact that prostate risk steadily rises as men age.

Besides the fact that selenium has excellent antioxidant properties that have been shown to help increase insulin efficiency, selenium also enhances the effect of vitamin E, making it a perfect match for any vitamin E regimen designed to help prevent prostate cancer.

Foods that contain selenium include fruits and vegetables (if grown in selenium-rich soil), beef, tuna, turkey, chicken, eggs and whole wheat bread. Brazil nuts contain more selenium than any other food: 840 mcg of selenium per ounce.