We create vitamin D when our bare skin is exposed to sunlight. Unfortunately, so few of us do that in these days of office jobs, video games, and sunscreen that the 2015 Dietary Guidelines Report flagged the national lack of vitamin D as a “public health concern” because “under consumption has been linked in the scientific literature to adverse health outcomes.” Too little vitamin D leads to weak bones, tiredness, depression, and even heart trouble. Low levels of vitamin D also make it harder to absorb calcium, another nutrient flagged by the Dietary Guidelines Report.
I experienced the tiredness brought on by vitamin D deficiency last year as a side-effect to a side-effect. I came down with a bad case of shingles last spring, just when I should have been frolicking outside and restoring my vitamin D levels after being bundled up for the winter. The pain killers I took for the shingles made me very sensitive to light, so I literally spent the summer in our dim basement. My doctor didn't think to check my vitamin D levels or suggest supplements until I complained about sleeping 12 to 14 hours a day even after the rash was gone. As soon as I started taking a D supplement, I started feeling more energetic and sleeping less.
I'd much rather get my nutrition from pure, whole foods instead of supplements, an approach recommended by the Dietary Guidelines. Wild mushrooms are an excellent source of vitamin D because they were grown with some sun exposure, but I don't have the knowledge to safely forage for them. I was amazed to find that you can increase the vitamin D in store-bought mushrooms that were grown in the dark just by exposing them to sunlight.
Portobello mushrooms that have been exposed to sunlight or UV radiation by their growers cost twice as much: about eight dollars a pound instead of four dollars a pound for untreated mushrooms. I buy the untreated mushrooms and put them outside on a cookie sheet for a few hours on a sunny day. According to a test done by Paul Stamets of Fungi Perfecti, shiitake mushrooms will create the most vitamin D when exposed to the sun gill-side up for 12 hours over 2 days. Just 8 hours of sunlight led to increase from 40 IU to 46,000 IU per 100 grams of mushrooms. I'm just after a little Vitamin D boost, though. The Medline Plus report on Vitamin D (see the bottom of this post) recommends just 600 to 800 IU a day for those over 1-year-old and recommends, as I do, that you talk with your doctor about your specific needs.
Mushroom Lettuce Wraps Recipe
Show off your heirloom lettuce by making these easy, flavorful wraps. Fill cool crisp leaves with warm, spicy fillings for a healthy appetizer or light meal. It's a great party treat too, especially if you let guests fill their own wraps. You can make all the fillings and clean the lettuce leaves in advance. Just make sure to serve the fillings hot and the leaves cold. Serves 2 as a main dish or 4 as an appetizer.
Ingredients• 8 ounces portobello mushroom caps
• 1/3 cup dried black beluga lentils or French green lentils
• 1 1/3 cups water
• 1/2 tsp salt
• 1 bay leaf
• 1 medium red sweet potato (about 8 ounces)
• 2 tsp sunflower oil or other neutral vegetable oil
• 1 tbsp minced ginger
• 2 cloves garlic, minced
• ¼ tsp ground chipotle or cayenne pepper
• 1 tbsp maple syrup
• 2 green onions
• 1 small head loose-leaf lettuce, such as butterhead
• 1/4 cup salted and roasted cashews or peanuts, chopped
• hot sauce to taste (optional)
1. Put mushroom caps gill-side up in a sunny spot for an hour or two between 10 am and 4 pm.
2. Put lentils, 2 cups water, and salt in a medium pot and soak for up to 12 hours. Add bayleaf, cover pot, bring to a boil over high heat, and then reduce heat to low so the water barely boils. Cook until lentils are tender but still hold their shape, about 30 minutes. Remove bayleaf.
3. Peel sweet potato and cut into small cubes, about 1/3 inch across. Put oil in a large skillet and heat over medium-low heat. Add ginger, garlic, and chipotle pepper to oil and stir, cooking for about 30 seconds until fragrant. Stir in sweet potato and 1/3 cup water and then cover skillet. Reduce heat to low and cook until tender, about 10 minutes. Drizzle sweet potatoes with maple syrup and stir to coat, then put in a covered bowl to keep warm while you cook the mushrooms.
4. Chop mushrooms into cubes about 1/3 inch across. Cut green onions into sections about ½ inch across. Cook mushrooms and green onions in the skillet used for the sweet potatoes, adding a little extra oil if needed to keep from sticking. Cook until mushrooms are tender and most of the juices have boiled off, about 10 minutes.
5. Cut leaves off lettuce head, rinse well, and dry in a salad spinner or by rolling leaves up in a clean kitchen towel. If you have more than you need, choose the prettiest ones for your lettuce wraps and save the rest for a salad later.
6. Fill each leaf with small spoonfuls of lentils, sweet potatoes, mushrooms, and cashews, with hot sauce as desired. Avoid overfilling the leaves. To eat, pick up a lettuce leaf and fold the edges in like a burrito. Bite and enjoy the mix of cool crispy lettuce, savory and sweet warm fillings, and crunchy nuts.
Read Best Sources of Vitamin D for more information about Vitamin D mushrooms.
Scientific Report of the 2015 Dietary Guidelines Advisory Committee, accessed March 17, 2015.
Vitamin D. Medline Plus, a service of the U.S. National Library of Medicine, accessed March 17, 2015.
Vitamin D Deficiency by Michael F. Holick, M.D., Ph.D. New England Journal of Medicine, July 19, 2007.
Photobiology of vitamin D in mushrooms and its bioavailability in humans by Raphael-John H. Keegan, Zhiren Lu, Jaimee M. Bogusz, Jennifer E. Williams, and Michael F. Holick. Dermato-Endocrinology 2013 Jan 1; 5(1): 165–176.
Place Mushrooms in Sunlight to Get Your Vitamin D by Paul Stamets, Fungi Perfecti, 08/06/12.
Photo by Linda Watson (c) 2015 Cook for Good, used by permission.
Check out Linda's website Cook for Good for more recipes and tips. Follow her on Twitter, Facebook, Instagram, and Pinterest. She is the author of Wildly Affordable Organic: Eat Fabulous Food, Get Healthy, and Save the Planet--All on $5 a Day or Less and Fifty Weeks of Green: Romance & Recipes.
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