What is the evidence that plant-based diets can decrease the risk of prostate cancer?

Eating a plant-based diet means that most of the foods you eat are from the plant kingdom and you less frequently eat animal foods. A typical plant-based diet has meals that consist of vegetables, starches (all grains, pasta, potatoes, rice, bread and bread products, beans/ legumes), fruit, nuts, and seeds. We add to these foods extra virgin olive oil, which is the juice of the olive, so it is a plant food and daily consumption of olive oil is related to numerous health benefits.

The original plant-based diet was the Mediterranean diet, which could also be classified as a vegetarian diet. Some countries included fermented dairy products and occasional seafood, but the majority of the food items were plant foods. The strictest form of a plant-based diet is a vegan diet – no animal products at all. The more plant products included, the healthier the diet.

Studies indicate that a vegan diet can be quite healthy. A study of Seventh Day Adventists men that categorized the participant’s diet as non-vegetarian, vegetarian, or vegan, found that only the vegan diet was related to lower prostate cancer risk,¹ meaning the consumption of only plant products decreased the risk of prostate cancer. Compared to those who ate a non-vegetarian diet, meaning frequent animal products, those following a vegan diet had a 35% decreased risk in prostate cancer after approximately eight years of follow-up. I acknowledge that a vegan diet may be a bit hard for people, but following a plant-based diet as often as you can should also provide benefits. Consider changing some meals in a week so that they contain more plant products.

There are studies showing a Mediterranean diet, which is by definition plant based, can protect from prostate cancer. A case-control study in Spain that included 733 men with prostate cancer and 1229 controls (men without prostate cancer) compared adherence to a Mediterranean, Prudent, or Western diet.² While both the Mediterranean and the Prudent diets contained vegetables and fruits, the Mediterranean diet contained olive oil, while the Prudent diet did not. No diet was related to the risk of being diagnosed with prostate cancer, but higher adherence to the Mediterranean diet was associated with a 32 % lower risk of Gleason score greater than 6, suggesting a Mediterranean diet that included olive oil provided protection for more aggressive prostate cancer.

A case-control study in Catania, Sicily that examined adherence to a Mediterranean diet and specific foods of the diet found a linear inverse relationship to diet adherence and risk of prostate cancer.³ For each point increase in the Mediterranean diet score diet adherence there was a 14% decrease in risk of prostate cancer and those reporting a diet with the highest adherence to a Mediterranean diet were 78% less likely to have prostate cancer.

Summary:

• A Mediterranean diet is a plant-based diet.
• Eating a diet with more plant foods in it may decrease your risk of prostate cancer, especially aggressive prostate cancer.
• Extra virgin olive oil, which is the juice of the olive, is a key ingredient in a plant-based diet.