Many of us have heard the colloquial saying “An apple a day keeps the doctor away” at some point in our lives. It first gained popularity in the 1920’s as adaptation of the old Welsh saying “Eat an apple on going to bed, and you will keep the doctor from earning his bread”. Some varieties like Golden Delicious don’t live up to the hype of apples having health promoting effects7. No need to worry, because some varieties of apples like Red Love and Bloody Ploughman are packed with phytonutrients and phytochemicals that do backup the hype. One of these phytochemicals is ursolic acid.
Ursolic acid is interesting phytochemical that has been popularly know since the early 20’s when it was discovered in apple peel. Coincidentally, the peel has been shown to have a much higher concentration of antioxidants and phytonutrients then the pomace9. What are some of the benefits of ursolic acid you may ask? Let’s take a look.
A study was conducted to determine how effective ursolic was against different types of breast cancer lines. The researchers found that 20 microMolar concentrations of ursolic acid were able to destroy all lines of breast cancer cells tested but had no effect on normal healthy human cells.1 Similar results were observed when studies were conducted for ursolic acid against the proliferation of colon 2, lung3, liver3 and prostate3 and bladder4 cancer cells.
Ursolic acid also strengthens our immune system. Our body’s immune system utilizes dendritic cells to help it fight against attack. One responsibility of dendritic cells is to process antigen material from threats to body and to “inform” T cells of the potential threat. A large amount of dendritic cells are found in tissue and some can be found in an immature state circulating in our bloodstream. A recent observed that dendritic cells treated with ursolic acid resulted in dendritic cells with increased maturity and activity for fighting against cancer.5
The next time you eat an apple remember the peel is actually the part of the apple with most concentrated amount disease fighting phytochemicals. Try going for the variety with the richest peel color like Red Delicious, Gloster or the aforementioned cultivars. Also freeze dried apple peels are a nice cheat snack to give the antioxidant band of the peels and the long shelf life typical of freeze dried foods. Apples aren’t the only good sources of Ursolic Acid. Herbs like rosemary and thyme are also good sources of it as well. Nonetheless below are some good sources freeze dried apples, rosemary and thyme.