Our California office is located close to Napa Valley, so we hear a lot about the benefits of a wine tasting here and there (*wink*). And because grapes are in season in September, we’ve decided to provide you with a grape-filled treat of our own! Where we are, it’s not quite cold enough for us to justify a piping hot Pumpkin Spiced Latte just yet, so we’re going to hold on tight to those last feelings of summer with this cool, refreshing grape frappe recipe.
Overall healthy ingredient profile
All of the ingredients in our grape frappe recipe are healthy! Can you believe it?! Grapes contain resveratrol, a phytochemical (a chemical that occurs naturally in plants) also found in red wine and peanuts and thought to be a preventive against cancer and heart disease. Grapes also contain ellagic acid, a chemopreventive substance that reduces glucose levels and is used to treat viral and bacterial infections. The frozen strawberries in this recipe add ellagic acid and vitamin C as well. Ginger is well known for combating nausea but also has lesser known cancer prevention properties and contributes to many remedies. Limes contain vitamin C and flavonol glycosides that have anticancer, antioxidant, and antibiotic properties. Mint leaves have calcium, phosphorous, vitamin C, D, E, small amounts of vitamin B complex, and are packed with antioxidants and phytonutrients. Mint has a potent phytochemical, perillyl alcohol, that is being investigated for cancer prevention.
Evidence for cancer prevention by ellagic acid
The benefits of ellagic acid will be the focus of this post. Ellagic acid prevents the binding of carcinogens to DNA and reduces inflammation, angiogenesis, and drug-resistance processes required for tumor growth and metastasis. In lab tests, ellagic acid caused cancer cells to go through the normal apoptosis process without damaging healthy cells. In plants, ellagic acid is combined with glucose to form ellagitanins; uptake of ellagic acid is higher in cancer cells since they consume about 15 times more glucose than other cells.
Sources of ellagic acid
Ellagic acid is a naturally occurring polyphenolic constituent found in 46 different fruits and nuts. Besides strawberries and grapes, other good sources of ellagic acid are raspberries, blackberries, and walnuts. For an interesting read on the best wild and cultivated sources of food containing ellagic acid see here and for a table showing average amounts in various food see here. It should be noted that although ellagic acid is the bioactive agent that offers protection, it is generally ingested in the form of ellagitannin, produced by plants from ellagic acid and glucose. Ellagitanins are water-soluble compounds that are easier for animals to absorb in their diets.
There isn’t enough reliable information available in humans about ellagic acid to know if it is safe in humans. One animal study in rats showed a decrease in weight but no other signs of toxicity. Small amounts of ellagitannins derived from natural sources may be more effective in our diet than purified ellagic acid.