We know that selenium can be helpful in lowering some autoimmune antibodies -- in particular, thyroid peroxidase antibodies (TPO) that can cause Hashimoto's disease. Selenium is also an important nutrient for overall immune function. Now, an Australian researcher has shown that selenium plays a key role in fertility.
A research team, led by Melanie Ceko, looked at the role of selenium in the ovaries, and found that selenium is crucial to the development of healthy ovarian follicles. Follicles are responsible for production of eggs in women.
According to Ceko:
Selenium is an essential trace element found in protein-rich foods like red meat, seafood and nuts. It is important for many biological functions, such as immune response, thyroid hormone production, and acts as an antioxidant, helping to detoxify damaging chemicals in the body. We’ve known for some time that selenium is important to men’s fertility, but until now no-one has researched how this element could be involved in healthy reproduction in women.
The researchers found exactly where selenium is located in the ovary, and in particular, the selenoprotein known as GPX1.
According to Ceko:
Our findings are important, because they show that selenium and selenoproteins are at elevated levels in large, healthy ovarian follicles. We suspect they play a critical role as an antioxidant during the late stages of follicle development, helping to lead to a healthy environment for the egg, We found that gene expression of GPX1 was significantly higher – in some cases double – in egg cells that yielded a pregnancy.
The researchers cautioned that more research is needed to understand how to optimize selenium for fertility, and that it’s not just a matter of taking more selenium supplementation.
What This Means for Women
Restrictive diets may result in selenium deficiency, or sub-optimal levels of selenium. Based on these findings, it may make sense for women of childbearing age to supplement with selenium. But, keep in mind, selenium at higher doses can be toxic. Experts recommend that the daily intake of selenium should not exceed 400 mcg (micrograms, not milligrams) per day, from all sources, including food and supplements.
Foods Highest in Selenium
- Brazil Nuts
- Cooked Oysters
- Cooked Tuna
- Whole-Wheat Bread
- Sunflower Seeds
- Lean Tenderloin Pork
- Lean Beef and Lamb
- Chicken and Turkey (Dark Meat)
- Crimini Mushrooms
Source: Metallomics, Melanie Ceko, University of Adelaide, Nov 17, 2014