Local Kale vs. Non-Local Kale: Amplified Nutrient Density in Locally Grown Foods
By Eminah Quintyne - Contributor to Dianne’s Call.
Eminah is a food science professional with an MPH in health policy and management and BS in nutrition and food science. Eminah is on her way to becoming a Registered Dietician Nutritionist in 2022 and is assisting Dianne’s call as part of her practical learning experience. Look for informative pieces from her spotlighting why local foods are often more nutritious.
If measuring the degree of excellence among fruits and vegetables in light of its worth and usefulness local compared to non-local is the standard to consider.
Local fruits and vegetables are foods that come from near you. They’ve been cultivated on nearby land, travel shorter distances to get to you and maintain the glory you want to consume.
Local fruits and vegetables are picked when ripe, are more nutrient-dense, and taste better than produce that isn’t local. The big idea is timing. Produce is freshest immediately after it is picked. When growers harvest produce that isn’t ripe to extend shelf life for transit and sales the integrity of that item’s nutritional composition is compromised.
Zach Snipes is the Horticulture Extension Agent for Clemson University’s Beaufort and Charleston county Extension office. He earned an M.S. in Plant and Environmental Sciences from Clemson University and has a B.S. in Biology from Presbyterian College. His expertise is in Horticulture with a focus on commercial vegetable and small fruit production in the Lowcountry. He is passionate about farming, utilizes integrative pest management to give plants optimal life, and fosters education to assist local growers. Zach likes to connect with the environment and get his fingers dirty. He grew up learning from generational farmers, picking peaches, and with a garden.
“Local produce has more nutrients than fruits and vegetables being trucked, or shipped from Chile or from far away. Once fruits and vegetables are picked their phytonutrients like antioxidants begin to break down. In transit fluctuations in heat and temperature changes the value of phytonutrients. With carrots after a week of refrigerated storage, they lose 80% of their vitamin C content. Local produce should be eaten within one to three days after it is picked. You want to eat produce that is picked when ripe and quicker to get more nutritionally speaking.” Said Zack.
Nutrients are chemical compounds that can only be seen through a microscope. They are classified into two categories called macronutrients and micronutrients. Macronutrients are protein, carbohydrates, and fats. This also includes water and fiber. Micronutrients are vitamins and minerals. Both give information to your cells to help enable your cells to carry out the instructions of their DNA code. Ultimately the chemical compounds in foods help us to function. That means to make our bodies work. Foods carry gems, particularly fruits and vegetables. Yes, gems called bio-active compounds and phytochemicals. There is more good news to the story than vitamins and minerals, and that part gets really good.
Kale is a well-known superfood. It comes in many varieties and is something of the Don Juan among green leafy vegetables. Think about your typical eight-ounce glass of water, now imagine a gallon of water that somehow fits in the same eight-ounce space that’s a superfood. These are foods that pack nutrient density and give your body a powerful blow in just a few bites. That’s pretty super.
The Carolinas have emerged as kale leaders, currently producing more than two-thirds of America’s annual kale output1. Kale is nutritious when eaten raw or cooked. The trick is not to overcook it or use too much water. You will lose a lot of the nutrients in the leaves by cooking it down too much or all the nutrients may get lost in excess water. There is the option of using the water as a broth and consuming it as a soup, but you have to be mindful not to cook it down too much.
According to a study conducted by the Centers for Disease Control Kale is ranked 15th on the list of “powerhouse” fruits and vegetables (a 100-g serving provides ≥10% of the daily value of 17 essential nutrients)1.
Data from research state kale is rich in several vitamins (A, K, C), and essential minerals (potassium, calcium, magnesium), and dietary fiber2. Vitamin K helps to regulate blood calcium levels, and aids in protein development needed for blood clotting and to build bones3. Vitamin C aids in the production of white blood cells known as lymphocytes and phagocytes which help to boost immunity by protecting the body against infection4. Vitamin C also helps to prevent oxidative stress around the brain, spine, and nerves protecting the body against dementia5, and stimulates collagen synthesis which may help to reduce wrinkles and encourage your skin to glow6. Magnesium is an essential mineral needed for the body to absorb vitamins C and D7.
Vitamins A, D, E, and K are fat-soluble vitamins meaning they must be dissolved in fat before being absorbed into your bloodstream. Good fats are avocado, safflower, sunflower, and olive oils. B Complex vitamins and vitamin C are water-soluble. They must be dissolved in water before being absorbed into your bloodstream. Water-soluble vitamins are generally quickly eliminated from the body through urine and are required in continuous daily supply to give our bodies the nutrients it needs.
There are cooking temperatures needed for varying fruits and vegetables to achieve nutrient bioavailability. That means to unlock the vitamins, minerals, bioactive compounds, and phytochemicals. The vitamins and phytonutrients in broccoli, tomatoes, and carrots actually become more bioavailable when cooked. Lycopene is a powerful antioxidant located in the cell walls of tomatoes. When heated the cell walls of tomatoes are broken down and the amount of lycopene in tomatoes is increased during cooking. Research states tomato products like tomato sauce, paste or juice contain 2-10 times as much available lycopene as uncooked tomatoes8. Glucosinolate is another potent antioxidant found in broccoli and when broccoli is cooked al dente via steaming or sautéing glucosinolate becomes bioavailable9.
Antioxidants donate electrons to free radicals stabilizing them without becoming unstable themselves10,11. Chemical bonds are atoms glued together or “bonded” together by electrons. The electrons are the key to keeping any chemical bond together. A free radical is a scientific name for what happens to electrons when chemical bonds break. That breach creates a number of atoms now called free radicals that scavenge around the body looking for another atom or molecule to bond with much like a chicken frantically running around with its head cut off. Having a head will make a chicken or any person a lot more stable. Free radicals may cause cellular damage, particularly through oxidative stress. Oxidative stress occurs in the body when there is a higher number of free radicals to antioxidants.
Research studies suggest that consumption of diets rich in plant polyphenols offers protection against the development of cancers, cardiovascular diseases, type 2 diabetes, osteoporosis, and neurodegenerative diseases like Alzheimer's. Polyphenols provide the greatest effectiveness in disease prevention and have demonstrated potential against antibacterial, antifungal, and antiviral activities12.
The presence of nutrients and bioactive compounds in foods tells a story of what food is made out of and how its components impact your body. I would like you to be my virtual buddy! Let’s take a closer look.
Atoms → Molecules/Compounds → Cells → Tissues → Organs → Organ Systems → Organism
What’s shown above is a snapshot of a seven-part sequence that communicates what human beings are composed of. Each term in the sequence is a part of a layer that builds upon the subsequent term. It’s good to know what you are made of to better understand what foods are best to put in your body. There is a level of organization in our bodies that builds from each other. [Click here for a drop-down list that explains each term of the seven-part sequence]
Research state cover crops have been used for centuries to provide multiple ecological benefits to both organic and non-organic cropping systems, such as preventing soil erosion, improving physical and biological properties of the soil, supplying nutrients nitrogen (N) and phosphorus (P), suppressing weeds, increasing soil water retention, and breaking pest/disease cycles1.
“All farms, whether considered organic or conventional, grow crops and animals for monetary value. All farmers are stewards of the land, no matter their production practice. Our local farmers work hard every day to keep their farms thriving which helps protect the land and support their local communities. The good news is that by purchasing products from local farms, you are not only supporting a local business and helping to protect the land, but you are getting a more nutritious food product. It’s a win-win for everyone. It just takes a little more effort to seek out, find, and purchase local produce.” Said Zack.
Kenneth Melton affectionately known as “Skinny” is the owner and farmer of Lowland Farms on Johns Island in South Carolina. Skinny runs a spring, summer, and winter Community Supported Agriculture program (CSA). CSAs are member groups that receive weekly shares of food from a certain farm (or groups of farms) in their region.
Skinny is an avid reader, he earned a B. A in English and decided supporting local farms and making sure they continue to exist is what is most important to him. He likes to plant rare varieties exclusively plants heirloom seeds and lives on the mantra of something someone once told him “Farmers are the first artist”. Lowland offers a beautiful heirloom kale mix that includes Red Russian, Lacinato a.k.a Tuscan or Dinosaur; Scarlet, and German green. They also offer a variety of potatoes like fingerlings, purple, masquerade potatoes, and provide green, purple, white, and yellow-green beans.
Lowland’s summer CSA bags are offered for 12 weeks April - July, at a weekly rate of $25 to $46 per small to large variety bag. Patrons are encouraged to purchase 12, six, or four-week bundles and can do so online at lowlandfarms.com. For inquiries about pricing contact Skinny at:
Skinny offers a small bounty of staple items in every bag. Summer bags include - A dozen eggs, potatoes, kale, squash, cucumbers, heirloom tomatoes, okra, various peppers, eggplant, herbs (dill, parsley, cilantro, basil), heirloom lettuces, and more. Farm pick-up is available daily and Lowland delivers on Thursdays and Fridays. Produce is also fresh-picked and for sale direct from Lowland Farms on Johns Island every Friday from 10 am to 4 pm. Lowland is located at 3702 River Road Johns Island, SC 29455.
“I encourage people to help preserve the livelihood of local farms and get better products. Develop a relationship with a farm in your community. Doing so saves farmers time. Get to know your local farmers, make the effort to get to know people in your community. You can find local growers through a CSA, farmer’s market, or choose a restaurant that supports farmers in your community.” Said Skinny
Skinny runs a 14-acre farm and says the CSA is the most direct way to alleviate costs for farmers. His produce is picked within 24 hours of being sold. Buying from him is a great way to ensure food is fresh and clean.
“People have direct access to this in your community. You don’t have to go to the grocery store, you can pick up a lot of staples direct from a farm”. Said Skinny
When it comes to eating healthy a rule of thumb is to color your plate. You want variety and should always work towards balance.
“Diet plays an important role in our overall health. People don't eat enough fruits and vegetables and the real issue is people don't eat seasonally. Farmers love what they do. There should be a shift in perspective to purchase locally and support the local environment. Farmers are keepers of the land helping to preserve the land and protect the environment through cover crops. Make an effort to buy from the local section of grocery stores, to buy local off restaurant menus, to shop at farmer’s markets, and get something from a farmer participating in a CSA.” said Zack.
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Huijskens MJ, Walczak M, Koller N, Briedé JJ, Senden-Gijsbers BL, Schnijderberg MC, Bos GM, Germeraad WT. Technical advance: ascorbic acid induces development of double-positive T cells from human hematopoietic stem cells in the absence of stromal cells. J Leukoc Biol. 2014 Dec;96(6):1165-75. doi: 10.1189/jlb.1TA0214-121RR. Epub 2014 Aug 25. PMID: 25157026.
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