Plant-Based Diets: Digging Through the Soil for Selenium
Plant-based diets have grown in popularity over the years for many reasons. Some consumers adopt vegetarian and vegan eating patterns to feel better, some do so to reduce inflammation and others choose to simply because of their personal preference. These plant-derived diets are thought to provide a variety of health benefits, but it is important to note that eliminating certain foods and/or food groups can also minimize the intake of specific nutrients. In fact, the consumption of vitamins and minerals like calcium, vitamin D, vitamin B-12, iron and selenium often decreases with plant-based diets. This raises the question: How do you ensure that you are getting enough of these nutrients?
One mineral that you may or may not know about is selenium. While only needed in small amounts (55 mcg per day for adults), selenium is considered an essential nutrient, which means that it must be obtained from the diet. The absence of this mineral could result in a selenium deficiency and lead to negative health consequences (National Institutes of Health). Your body uses selenium for a number of health-promoting functions, like the protection of cells against oxidative stress. It is well-known that free-radical damage caused by oxidative stress can contribute to a variety of chronic health conditions, like heart disease and cancer. As a powerful antioxidant, selenium helps protect cells from this damage. It is also vital for thyroid hormone function, DNA synthesis, maintaining a healthy immune system and more.
Why should selenium matter more for those who eat plant-based diets? Well, when you look at the top foods that provide selenium, you will find that many of them are animal derived. While there are a variety of plant foods that contain selenium, the specific mineral content of these foods depends on the selenium content of the soil where the food is grown. While most vegans in the United States appear to have adequate intakes of selenium, low intakes have been reported in vegans and vegetarians in other parts of the world where soil selenium is low (Lancet, 2012).
Individuals with HIV, who are undergoing dialysis or who have a digestive order like Crohn’s disease may be at a greater risk for selenium deficiency. In addition, selenium intake is especially important for those with thyroid disease and thyroid nodules, those with cancer or weakened immune function, and those who are pregnant or already deficient (National Institutes of Health).
Individuals who eat plant-based diets should look for plant foods with a high selenium content. Brazil nuts top the charts with approximately 544 mcg per ounce (Am J Clin Nutr., 2008)! They can be eaten as a snack or chopped and included in dishes like oatmeal, salads and yogurt parfaits. Other plant-based sources of selenium include whole grains, brown rice, soy products, seeds and beans. However, when foods high in selenium are not an option, a selenium supplement can be an appropriate way to ensure adequate consumption of the mineral. If you are concerned about your selenium intake, be sure to discuss supplementation with your physician.