Eat These and You May Live Longer, New Study Says

(photo by Getty Images)A group of international scientists has located a possible fountain of youth, and it's in our kitchens. A new study in the Journal of Nutrition reports that older adults who consume higher amounts of polyphenols have a 30 percent chance of living longer. Polyphenols are micronutrients found mainly in fruits, vegetables, legumes, nuts, grains, coffee, and tea. Evidence suggests polyphenols have a role in preventing cancer, cardiovascular disease, inflammation, osteoporosis, and other degenerative diseases.

Related: Great-Tasting Antioxidant Treats

The 12-year study, which involved more than 800 participants, is the first to use a specific biomarker (in this case, urine analysis) to measure polyphenol levels, instead of relying on questionnaires. "The results corroborate scientific evidence suggesting that people consuming diets rich in fruit and vegetables are at lower risk of several chronic diseases and overall mortality," lead author Raúl Zamora Ros, PhD, of the University of Barcelona, said in a statement. "This methodology makes a more reliable and accurate evaluation of the association between food intake and mortality or disease risk," added colleague Cristina Andrés Lacueva, PhD.

More on Yahoo: Longest-Living Bat Holds Clues to Longevity

A polyphenol-rich diet includes at least 650 milligrams a day. Below is a list of 20 commonly available foods that are among the 100 richest dietary sources of polyphenols (polyphenol content listed as mg/100 g serving):

  • Cocoa powder (3448 mg)
  • Dark chocolate (1766 mg)
  • Black olives (569 mg)
  • Green olives (346 mg)
  • Hazelnuts (495 mg)
  • Pecans (493 mg)
  • Soy flour (466 mg)
  • Plums (377 mg)
  • Cherries (274 mg)
  • Artichokes (260 mg)
  • Blackberries (260 mg)
  • Strawberries (235 mg)
  • Red raspberries (215 mg)
  • Red chicory/radicchio (235 mg)
  • Whole-wheat flour (201 mg)
  • Almonds (187 mg)
  • Black grapes (169 mg)
  • Red onion (168 mg)
  • Apple (136 mg)
  • Spinach (119 mg)

Don't stick to just the top-listed foods, though. "Any plant-based foods are good in their whole form," Angela Lemond, RDN and spokesperson for the Academy of Nutrition and Dietetics, tells Yahoo Shine. In general, polyphenol-rich foods are bright-or dark-colored and have a strong or astringent flavor. She recommends adding fruits and vegetables to breakfast and lunch, since most people focus on their dinner menus. Another trick is to slip vegetables into sandwiches and pack a colorful salad for lunch. She also says, "Branch out from your favorites and experiment with seasonal produce." The orange and red foods that are now hitting markets and farm stands are great sources of polyphenols. For kids, Lemond suggests cutting fruits and vegetables into snack sizes and storing them at eye level in the refrigerator.

Polyphenols are found in thousands of combinations in hundreds of different foods, and for maximum benefit, its helpful to eat a variety over the course of the day to keep blood levels high. Consume produce when it's fresh, because the beneficial compounds deteriorate with age. "There is also some destruction with heat," says Lemond. Cooking, especially deep-frying and boiling, can destroy them, but steaming retains the highest degree. Because some nutrients are released by cooking, she generally recommends eating a mixture of raw and cooked food. Processing foods can destroy the healthy compounds, so choose whole grains that are minimally processed. Also, leave skins on fruits and vegetables for maximum benefit.

Spices and herbs such as cloves, rosemary, oregano, and many others are superrich in polyphenols, so season your meals liberally. Beverages contain polyphenols too, especially coffee, green and black tea, red wine, and beer. Dark juices and citrus juices are good choices, but to keep calories in check, avoid high levels of added sugar.

To learn more, Phenol-Explorer is an open-access database that lists values for over 500 different polyphenols found in more than 400 foods. It also includes information on the effects of processing and cooking on nutrient retention.

Also on Shine:

7 Super-Efficient, Super-Effective Ways to Clean Your Home

Smell Fantastic Without Wearing Perfume

10 Unbelievable Diet Rules Backed by Science