The trace mineral selenium certainly doesn’t get the attention it deserves. The following items are not in priority order because they are all extremely important.
- Thyroid. An under-functioning thyroid gland can be responsible for depression, high cholesterol, constipation, pain, heart trouble, menstrual irregularities, fatigue, hair loss, memory issues and other problems. Learn more. Inadequate intake of selenium is one cause of thyroid problems because selenium is needed to convert the storage form of thyroid hormone (T4) into the active form (T3). Here is an example study showing that selenium and zinc help thyroid function.
- Helps zinc. On the radio show (especially when Bill Sardi is the guest) we frequently discuss the critical importance of zinc to our immune function, general health and longevity. However, zinc can be bound up and selenium frees it. In one study, zinc plus selenium improved immunity in older animals after vaccination.
- Antioxidant. As you probably know, our cells are under constant attack by “free radicals” that are also known as “oxidants”. Free radicals are a major cause of inflammation, cancer, heart disease, Alzheimer’s, and so on. Selenium is one of the nutrients offering significant protection from these oxidant attacks. One way it does so is by being used in glutathione peroxidase (master antioxidant/detoxifier).
- Selected benefits. Given the fundamental way selenium operates, we can expect a wide range of downstream benefits. The following are just examples.
- Cancer.Many studies show that cancer patients have low levels of selenium. (And vitamin D.)
In an exciting interview with Dr. Richard Passwater, the researcher told us about a randomized trial showing that an organic form of selenium yeast cut overall deaths from cancer in half! It also dramatically cut the incidence of various cancers (e.g. prostate cancer reduced by 63%, colon cancer by 58%, etc.). The inorganic forms of selenium pills (e.g. the more common sodium selenite and sodium selenate), while perhaps useful in some way, have not been shown to have this dramatic cancer protective effect. Sadly, when the National Cancer Institute began a study supposedly designed to “replicate” that research, they used the wrong kind. Jarrow Formulas’ product SeleNext uses the form implemented in the original study.
Selenium’s functions listed above would help explain the anti-cancer effects, but there may be more ways. Studies show that supplementation even to individuals with normal blood selenium levels resulted in a dramatic improvement in the ability of lymphocyte type immune cells to kill tumor cells and a large rise in the activity of natural killer cells.
- Alzheimer’s. It does not prove cause and effect, but several studies have demonstrated that Alzheimer’s patients have lower blood levels of selenium.
- Autoimmune disease. Low levels of trace minerals such as selenium is a common finding among patients suffering autoimmune diseases. Example study.
- Postpartum Depression.This study said: “…supplementation with selenium during pregnancy might be an effective approach for the prevention of postpartum depression.”
Form and quantity matter. The foods shown in the photo are good sources of selenium if the soil in which the foods are grown contain adequate selenium. Most people don’t eat Brazil nuts which is the richest source. It seems smart to supplement without going over 400 mcg per day which is the safe upper limit of selenium for food and pills combined. (Government site that lists food amounts.)
The multivitamin / mineral that I take (Molecular Multi) contains 120 mcg of selenium as amino acid chelate. That means the mineral is carried by a component of protein to make it more like food. In contrast, Centrum Silver only offers 19 mcg. and that is sodium selenate an inorganic form that, according to Wikipedia, is also used as an insecticide.