Overview
Zinc is an essential mineral that is needed by the body for a wide assortment of tasks. Zinc is involved in normal cell function, immune function and also plays a role in your ability to taste and smell. Zinc is unique because the body does not contain a zinc storage system and relies on a consistent daily intake. It is particularly important during adolescence and pregnancy, times in the lifecycle when the body is undergoing increased growth and development. Similar to iron, zinc absorption can be inhibited by the phytates which are found in grain and plant sources of the mineral, so adequate intake of zinc-rich foods is particularly important for vegetarians and vegans [i,ii].
Daily Recommendations
Women age 19 and older: 8 mg/day
Men age 19 and older: 11 mg/day [i]
In cancer, the risk of zinc deficiency is increased, particularly among those with head and neck cancers and gastrointestinal cancers, which can impair zinc absorption. Because of zinc’s role in taste and smell perception, it has been proposed as a possible treatment for taste changes/alterations and mouth sores. However, studies are still conflicting and more research is needed before the benefit of zinc can be confirmed. Excessive zinc intake should be avoided, as some studies have shown that excessive zinc can increase the risk of prostate cancer [iii].
Zinc Deficiency
Zinc deficiency in developed countries is very rare and is usually only seen in populations with gastrointestinal disorders, vegetarians or vegans, and pregnant or lactating women. As mentioned above, zinc deficiencies may be common in patients with head and neck cancers and it is therefore important to be aware of the signs and symptoms associated with a deficiency. Early signs of zinc deficiency include growth retardation, loss of appetite, and impaired immune function. More serious signs of deficiency include hair loss, diarrhea, impotence, eye and skin lesions, delayed wound healing, taste changes and fatigue [i].
** If instructed by a medical professional to take a vitamin or mineral supplement, it is important that these instructions are followed. In some cases, food sources of vitamins and minerals will not be sufficient for addressing nutritional inadequacies. **
Sources of Zinc:
Below is a list of the most common food sources of zinc.
- Oysters
- Beef
- Crab
- Beans
- Chicken
- Pork
- Yogurt
- ¼ cup quinoa
- 1/3 cup water
- 2 cups cooked black beans or 1 (15 ounce) can
- 2 tablespoons minced red onion
- 1 tablespoon chopped green onion
- ¼ cup minced jalapeno, fresh or canned
- 2 cloves garlic, minced
- ½ cup old fashioned rolled oats
- ¾ teaspoon cumin
- ½ teaspoon salt
- ½ teaspoon garlic powder
- ¼ dried oregano
- 1/8 teaspoon cayenne pepper
- 1 large egg
- 2 tablespoons olive oil
- Burger buns
- Lettuce (optional)
- Red onion (optional)
- Mayo dressing (1/4 cup mayonnaise mixed with 2 tablespoons Sriracha) (optional)
- In a medium saucepan bring quinoa and water to a boil. Once boiling, reduce heat to low and simmer, cooking covered for 12-13 minutes. Once done, fluff the quinoa and set aside.
- Drain and rinse black beans and finely chop or mince your vegetables.
- In a large bowl, mash the black beans into a paste with a few chunks left intact.
- In a food processor, process oats until they resemble an oat flour. This step is optional, whole oats can still be used however burgers may not hold together as well.
- To the large bowl, add oat flour, quinoa, red onion, green onion, jalepeno and seasonings.
- Add egg and mix together.
- Divide mixture into four portions and shape into burger patties.
- Let burgers sit in refrigerator for at least 5 minutes to allow them to set.
- Pour a tablespoon of oil in a skillet and heat on medium-heat.
- Cook the burgers for a few minutes on each side, till they develop a golden crust.
- Top burgers as desired with lettuce, onion, ketchup, mayo or mustard. Enjoy!
References:
[i] Zinc: Fact Sheet for Health Professionals 2018; https://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/. [ii] Zinc 2018; https://www.mskcc.org/cancer-care/integrative-medicine/herbs/zinc. [iii] Ressnerova A, Raudenska M, Holubova M, et al. Zinc and Copper Homeostasis in Head and Neck Cancer: Review and Meta-Analysis. Curr Med Chem. 2016;23(13):1304-1330.