The popularity of our dog diminished when he dug up my flower planter last week.  The planter was beautiful.  But there was no need to look for summer-flower replacements.  Whether I like it or not, the fall colors are upon me, deep green, red, orange, yellow of mums, autumn trees and sunsets that shout, “Gorgeous!” in the late summer Nebraska air.   

It’s as though the artist changed pallets. You see it everywhere, even at farmers’ market where late summer produce is abundant.  That color, my friends, is one of the ways you recognize polyphenols in your farmer’s market bag this fall.  Why should we care about polyphenols?

Polyphenols are plant compounds that contain one or more phenolic rings.  In plants, polyphenols promote health and provide disease protection.  They act similarly in our body when we consume them. 

They are plentiful in skins and seeds of many plants and abundant in deep colored and strong flavored vegetables.  For example, strong flavored, dark kale contains more polyphenols than iceberg lettuce.  A good rule of thumb when produce shopping is look for color!

The four major classes of polyphenols and examples:

1. Flavonoids: berries, beets, red and yellow  onions.
2. Phenolic acids: tomatoes, strawberries, onion skins, grains, tea.
3. Stilbenes: grape skins, berries.
4. Lignans: flax seed, sesame seed, kale, broccoli, cauliflower.

Polyphenols are responsible for many wonderful health promoting benefits.  They decrease inflammation and serve as antioxidants to prevent DNA damage in cells.   Other health effects include anti-aging, cardiovascular health, help with blood pressure and blood sugar regulation.  In addition, they strengthen the gut wall, serve as protection for the brain and nervous system, and interact with the immune system.

How are these far-reaching effects accomplished?   Not by the typical process of small bowel digestion and absorption!   Ninety-five percent of these phytonutrients transverse twenty-one feet of the gastrointestinal track to make it to the colon undigested, where they become food for the microbiome living there.  We call them prebiotics for the probiotics (the good gut bacteria).  As the microbes digest this food, they produce various metabolites and short-chain-fatty acids which are responsible for the previously mentioned positive health effects.   

So how do we maximize our intake of these health-promoting friends?   Farming methods and freshness matter.  Polyphenol content is affected by water, soil, plant maturity, transport and storage.  Vegetables picked green and ripened in storage have lower polyphenol content.   Exposure in storage to light, heat, and oxygen decrease them.  Food preparation does, too!  You can augment the polyphenols on your plate if you lightly sauté or steam your supper vegetables.  Polyphenols are lost in boiling water but are activated through steaming and sautéing. 

Looking to purchase local produce?   The North Platte Farmer’s Market is open through October.  Want to appear geeky?  Ask  a vendor for some polyphenols….or just say , “One tomato, red onion and a bunch of beets, please. “ 

Nebraska fall polyphenols: 

• Tomatoes