Pumpkins aren't just for Halloween carving and Thanksgiving pies. The seeds they contain are full of beneficial nutrients. One of the most important minerals in pumpkin seeds is zinc, an antioxidant that helps protect against age-related diseases and assists in fighting colds and healing wounds.
Pumpkins were an important food among the Native Americans and belong to the same gourd family of plants that includes cantaloupe, cucumber and squash. Pumpkin seeds, also known as pepitas, are flat and dark green and may either be covered in yellow husks or without any shells at all, depending upon the variety of pumpkin. Pumpkin seeds contain the minerals phosphorus, magnesium and manganese, iron and copper, as well as protein and vitamin K. According to the World's Healthiest Foods website, 1/4 cup of raw pumpkin seeds contains 2.57 mg of zinc or 17.1 percent of the Recommended Daily Allowance of zinc for healthy adults.
Zinc is required by your body to manufacture 100 different enzymes, and it also supports your immune system, protein synthesis, DNA synthesis, the healing of wounds, normal growth and development and your sense of taste and smell. Because many foods rich in zinc, such as red meats, contain saturated fat that contributes to inflammation in your body, having a zinc-rich plant source such as pumpkin seeds is a healthier alternative.
A zinc deficiency can cause poor night vision, loss of appetite and weight loss, delayed wound healing, a decrease in your sense of taste and smell, hair loss, a reduced ability to fight infections, eye and skin lesions, mental lethargy and improper development of reproductive organs in embryos. A mild zinc deficiency isn't uncommon, although most people can get all they need from foods such as pumpkin seeds. Low zinc levels are more commonly found in the elderly, alcoholics, anorexics and people on severely restricted diets. If you have a malabsorption syndrome, such as Crohn's disease or celiac disease, you may also be deficient in zinc.
Although studies investigating the link between zinc and prostate health are mixed, according to the World's Healthiest Foods site, zinc may contribute to positive benefits pumpkin seeds have shown in treating prostate conditions such as benign prostatic hypertrophy. The primary cause behind these effects are carotenoids found in pumpkin seed oil. The Linus Pauling Institute studied the effects of zinc on prostate cells in vitro and found that even low zinc treatments resulted in a marked decrease in cell viability of benign prostate hyperplasia cells. Another benefit for men from zinc found in pumpkin seeds is related to bone density. Research by Taisun H Hyun, et al, and published in the "American Journal of Clinical Nutrition" in 2004 found a direct link between low dietary intake of zinc and osteoporosis of the hip and spine in the male study subjects, who ranged in age from 45 to 92. The National Institutes of Health have reported on other studies that show promise in using zinc to boost immune function, prevent diarrhea among children in developing countries, treat age-related macular degeneration and lessen the severity of symptoms from the common cold.
While it's difficult to get too much zinc from pumpkin seeds and other foods, signs of zinc toxicity include chills, fever, nausea, vomiting, loss of appetite, cramping, diarrhea and headache. According to the Mayo Clinic, symptoms of a severe zinc overdose, usually found in people taking supplements, include chest pain, dizziness, fainting, shortness of breath and yellow eyes or skin.