Nutrition and Wound Healing: An Introduction to Dietary Vitamin Sources
by Mary Ellen Posthauer RDN, CD, LD, FAND
As we appreciate the glorious fall foliage, the crisp sunny days and marvel at the vibrant chrysanthemums in rich jewel tones, we also enjoy hearty meals and soups that incorporate seasonal vegetables. Food is a common, universal topic discussed while caring for clients with wounds. After all, everyone eats and has an opinion on what should be purchased and how meals should be prepared.
Registered dietitians and health care professionals should advocate for consuming balanced meals that include good sources of vitamins and minerals. So, what do we mean by "good sources"? This month, let’s focus on vitamins and take advantage of the colorful fall fruits and vegetables.
Vitamins are organic compounds that occur naturally in a variety of foods and are essential for the normal physiological function in the body. There are eight water-soluble vitamins and four fat-soluble ones, and all are required in small amounts (micrograms or milligrams).
Vitamin C or ascorbic acid is probably the most discussed micronutrient related to wound healing. However, there is no evidence that mega doses of ascorbic acid accelerate wound healing unless the person is deficient. Vitamin C is an antioxidant that reduces free-radical damage in cells, boosts immunity and is required for the synthesis of collagen. Good sources of vitamin C include citrus fruits and juice, kiwi, tomatoes, tomato products, peppers, broccoli, strawberries and Brussels sprouts. Taking more than 2,000 milligrams daily for a prolonged period of time can result in nausea or diarrhea.
B vitamins include thiamin, riboflavin, niacin, B6, folate, and B12. B vitamins function in energy producing metabolic reactions. While thiamin, riboflavin, niacin and B6 each have specific functions, the connection to wound healing occurs in individuals with a poor diet or chronic alcohol abuse. Pork, legumes, nuts and enriched whole grain products are good sources of thiamin. Riboflavin is found in milk, milk products, organ meats, spinach and enriched products. Organ meats, beef, poultry, fish and enriched cereal and bread are all sources of niacin. B6 is found in fortified foods as well as bananas, carrots and potatoes.
B12 is essential for red blood cell formation and is key to folate metabolism. Symptoms of B12 deficiency include weakness, fatigue and megaloblastic anemia. B12 is found naturally only in foods from animal sources such as meats, liver, and milk, but fortified cereal is also a good source; therefore, strict vegetarians and vegans are at the greatest risk for B12 deficiency. Folate plays a role in the metabolism of amino acids (the building blocks of protein) and in formation of DNA synthesis required for cell division. Megaloblastic anemia is a sign of a folate deficiency. Enriched grains, cereals, and orange juice along with green leafy vegetables, lentils and liver are good dietary sources of folate.
Fat-soluble vitamins, including vitamins A, D, E, and K are stored in the liver and fatty tissue when not used. Vitamin A is essential for vision, maintaining healthy cells, and regulation of the immune system and deficiencies have been associated with delayed wound healing and increased risk for infections. While supplementing with vitamin A has not been effective for wound healing, it has been demonstrated to improve delayed healing of wounds caused by taking corticosteroids. Good sources of vitamin A include liver, deep yellow and dark green leafy vegetable such as kale, spinach, sweet potatoes, acorn squash, and broccoli.
Vitamin D is synthesized by sunlight and plays a critical role in calcium and phosphorus utilization for bone formation. Adequate vitamin D intake can decrease the risk of osteoporosis and fractures particularly in older adults. Falls lead to reduced mobility that increases the risk for pressure ulcers. Reduced levels of vitamin D are associated with loss of lean muscle mass leading to diminished strength and can contribute to frailty, falls, and loss of physical function. Vitamin D deficiency is the most prevalent nutritional deficiency for older adults regardless of their race or ethnicity. Good sources of vitamin D are milk, dairy products fortified with vitamin D, salmon, sardines, and herring. Plants are poor sources of vitamin D so vegan wound clients may require a supplement.
Vitamin E does not play an active role in wound healing but functions as an antioxidant along with vitamin C. Vegetable oils along with nuts (almonds and hazelnuts), sunflower seeds and fortified cereals are good sources. Mega doses of vitamin E interfere with blood clotting.
Vitamin K plays a vital role as a cofactor involved in the synthesis of blood coagulation factors for bone metabolism. A deficiency is characterized by hemorrhage expressed by an increase in clotting time. Individuals taking antibiotics for long periods of time may become deficient in vitamin K since antibiotics can destroy intestinal vitamin K. Vitamin K is present in the bacteria in the colon or can be obtained from food including vegetable oils and dark green vegetables.
Encourage your wound clients to enjoy an abundance of colorful fruits and vegetables and pair them with whole grain products and protein foods.
Next month we’ll explore the role of minerals in the diet.
Have a Happy Thanksgiving.
About The Author
Mary Ellen Posthauer RDN, CD, LD, FAND is an award winning dietitian, consultant for MEP Healthcare Dietary Services, published author, and member of the Purdue University Hall of Fame, Department of Foods and Nutrition, having held positions on numerous boards and panels including the National Pressure Ulcer Advisory Panel and the American Dietetic Association's Unintentional Weight Loss work group.
The views and opinions expressed in this blog are solely those of the author, and do not represent the views of WoundSource, Kestrel Health Information, Inc., its affiliates, or subsidiary companies.