How your daily glass of milk could increase prostate cancer risk?

Men who consume a greater intake of milk may face a significantly higher risk of prostate cancer, according to a new study conducted by researchers at Loma Linda University Health.

The Dairy foods, calcium intakes, and risk of incident prostate cancer in Adventist Health Study-2 examined the dietary intakes of 28,737  men whose calcium and dairy consumption varied widely. All participants were free of cancer when the study commenced.

A questionnaire was provided to participants which included demographics, family history of prostate cancer, physical activity, alcohol consumption, prostate cancer screening, and BMI.

Upon the completion of the study, researchers examined state registries to follow up on the participants’ prostate cancer status. The registries reported 1,254 new prostate cancer cases among the participants during the follow-up.

The study found that men who consumed about 430 grams of dairy per day (1 ¾ cups of milk) faced a 25 per cent increased risk of prostate cancer compared to men who consumed only 20.2 grams of dairy per day (1/2 cup of milk per week). Also, men who consumed about 430 grams of dairy per day faced an even greater increase in risk when compared to men with zero dairy intake in their diets.

Dairy foods, calcium intakes, and risk of incident prostate cancer in Adventist Health Study–2 https://t.co/uc5YU5Lobd

— D.K.R. Boyd (@ReflectingMan) June 9, 2022

The study’s principal investigator and professor at Loma Linda University School of Medicine and School of Public Health, Gary Fraser, MBChB, PhD said the study’s findings “add important weight to other evidence associating dairy products, rather than non-dairy calcium, as a modifiable risk factor for prostate cancer”.

“Most of the continuing increase in risk is done with by the time you get to 150 grams, about two-thirds of a cup of milk per day,” Fraser said in a statement. 

“It’s almost as if some biological or biochemical pathway is saturated at about two-thirds of a cup of milk per day.”

Fraser indicated that the possible link between prostate cancer and dairy milk might be the sex hormone content of dairy milk.

“One interpretation is that dairy foods, or some closely associated unknown risk factor, are causally related to the risk of prostate cancer,” he said.

Up to 75 per cent of lactating dairy cows are pregnant, and prostate cancer is a hormone-responsive cancer. Previous reports have found an association between the intake of dairy and other animal proteins with higher blood levels of a hormone named insulin-like growth factor-1 (IGF-1) which is thought to promote certain cancers, including prostate cancer.

Although further investigation is needed to determine the way in which dairy consumption impacts the increased risk of developing prostate cancer, Fraser cautions men with a family history of prostate cancer or other risk factors should remain “cautious” about their dairy intake.

“If you think you’re at higher-than-average risk, consider the alternatives of soy, oat, cashew, and other non-dairy milks,” he said.

According to the Cancer Council, prostate cancer is the second most common cancer diagnosed in Australian men and the third most common cause of cancer death.

It’s estimated that one in 6 men will be diagnosed with prostate cancer by the age of 85. It is more common in older men, with over 63% of cases diagnosed in men over 65 years of age.

IMPORTANT LEGAL INFO This article is of a general nature and FYI only, because it doesn’t take into account your personal health requirements or existing medical conditions. That means it’s not personalised health advice and shouldn’t be relied upon as if it is. Before making a health-related decision, you should work out if the info is appropriate for your situation and get professional medical advice.