Last month we reported on a study which suggested  eating fruits and vegetables may help you live longer. This month we offer more convincing evidence that a plant-based diet is linked to a longer, healthier life. This time the researchers reveal an association which might indicate why! The September 2013 multi-institutional study was published in the Journal of Nutrition and shows that survivors had a 14% higher level of a biomarker for fruit and vegetable consumption that comes from the antioxidant polyphenolic compounds responsible for giving fruits and vegetables their vibrant colors.

A total of 807 men and women age 65 years and older from the Chianti region of Tuscany, Italy, were enrolled in the study. Immediately upon joining the study researchers estimated the participants’ total dietary polyphenol (TDP) intake by the standard food frequency questionnaire or FFQ but in addition they also decided to measure the participants total urinary polyphenol (TUP) concentration. The appearance of these polyphenolic biomarkers in the urine indicates that these compounds actually passed through the body and is a direct measurement of the amount of these compounds the participants have been exposed to. The researchers hypothesized this measurement to be a more accurate indicator of actual consumption rather than the estimation they got from the FFQ. During the twelve years following their enrollment 34% (274) of the study participants had died, 41% (112) from cancer, 24% (66) from cardiovascular disease and 35% (96) from a variety of other causes. The authors then correlated the TDP (estimated) and TUP (measured) values with mortality using statistical models. After adjusting for potential confounders such as age, sex, BMI, smoking status etc. the baseline TUP was about 14% higher in study survivors versus the deceased while the baseline TDP was no different. Further analysis of the data revealed those in the highest third of TUP measurements had a 30% lower mortality rate than those in the lowest third.  Again, the TDP was no different. The authors suggest that older participants with a low TUP measurement could be at higher risk of death thus a high dietary intake of polyphenols that you can only get from plant-based foods may be associated with longevity. This association was not picked out by the FFQ derived TDP.

So, what is the best way to increase your polyphenol intake? Simple, eat more delicious fruits and veggies! Not only might you live longer you could also enjoy healthier skin, lower blood pressure and even protection from cosmic radiation! So what do you have to eat to get to be in that top third of TUP discussed in the study? Well the FFQ can give us a good idea of that, with the top third of polyphenol consumption being equivalent to what you could get by eating about two cups of blueberries, or a red delicious apple and a banana each day, not much really when you consider that if you fulfilled the 9 to 13 servings of fruit and vegetable recommendation every day you would be way above this minimum!

Published November 1, 2013