Selenium is an essential mineral which is found naturally in soil and water. It is considered a “trace” mineral because it is only required in very small amounts for healthy living. Like vitamins C and E, selenium has been shown to be a potent antioxidant which helps protect your body (and bones!) from the damaging effects of free radicals. It has also been shown to improve your immune system, protect against arthritis, maintain normal thyroid function, and it also plays a role in male and female fertility.
How Much Selenium Do You Need?
With the typical American consuming 100 micrograms of selenium each day, selenium deficiency is very rare. However, certain populations in Asia, Africa and Europe have been shown to struggle to get their daily needs through diet alone.
The RDA of selenium for both men and women is 55 micrograms each day. The safe “upper limit” for selenium is 400 micrograms daily, which would include both selenium consumed through your diet as well as supplements.
Selenium Deficiency Is Associated With These Diseases
- Osteoporosis
- Heart disease
- Joint damage and arthritis
- Weakened immune system
- Thyroid disease
- Infertility
Selenium and Your Bones
Researchers have discovered a link between selenium and healthy bones. Selenium is a necessary building block of several antioxidants (including glutathione peroxidases and thioredoxin reductases) which work together with other antioxidants to protect your bones from the damage and inflammation caused by free radicals. When selenium levels are low, this sets the stage for bone damage to occur.
When your bones are attacked by free radicals, they respond in a way that leads to fewer bone-building osteoblast cells, and at the same time increases the activity of bone-breakdown osteoclast cells. This combination has been shown to make bones more likely to break. Let’s take a closer look at the studies which have provided insight into the link between selenium and your bones.
Selenium Deficiency Decreases Your Body’s Ability To Form Healthy Bone-Building Osteoblast Cells.
- Bone-building osteoblasts are made from precursor cells known as BMSCs. One study showed that selenium deficiency decreases your body’s ability to form antioxidants. Without antioxidants to protect BMSCs from free radical damage, fewer healthy bone-building osteoblasts were formed. When selenium was added to fix the selenium deficiency, this process was reversed!
Selenium Deficiency Increases Bone-Breakdown By Osteoclast Cells.
- One study showed that mice who were given a diet low in selenium experienced changes in their bone structure over time. There was a loss of bone density and structure.
- An observational study showed that pediatric patients in Germany who were fed a formula which lacked sufficient selenium had low bone density compared to other children.
- An additional study compared blood levels of selenium to bone breakdown. Researchers found that higher blood selenium levels led to less bone breakdown. This study also showed that higher selenium levels were associated with improved bone density as well.
Selenium Deficiency Is Associated With An Increased Risk Of Fractures.
- A study involving an elderly group of smokers found that those who consumed increased amounts of selenium through their diet were less likely to fracture their hip.
The link between antioxidants and bone health is certainly promising, and a clear connection is undeniable. What we need now are studies that are specifically designed to see if supplementation of antioxidants can directly decrease the risk of breaking bones in people with osteoporosis. Until then, it makes sense to at least get the RDA of antioxidants (including selenium, vitamin C, and vitamin E) through your diet and supplements. There is not enough information to support relying solely on antioxidants as a treatment for your osteoporosis.
How Can You Get More Selenium Through Your Diet?
Selenium is found in a variety of sources including nuts, fish, whole wheat grains, meat and dairy. Take a look at the following list to find ways to improve your selenium intake.
- Brazil Nuts (1 ounce): 543 mcg
- Tuna (3 ounces): 92 mcg
- Oysters (3 ounces): 65 mcg
- Shrimp (3 ounces): 47 mcg
- Salmon (3 ounces): 39 mcg
- Pork (3 ounces): 32 mcg
- Beef (3 ounces): 30 mcg
- Chicken (3 ounces): 26 mcg
- Whole Wheat Bread (2 slices): 16 mcg
- Egg (1 large): 15 mcg
- Milk (1 cup): 7 mcg