selenium

Introduction

Selenium is an essential trace mineral.
Where is it found?
Brazil nuts are the best source of selenium. Yeast, whole grains, and seafood are also good sources. Animal studies have found that selenium from yeast is better absorbed than selenium in the form of selenite.1
Selenium has been used in connection with the following conditions (refer to the individual health concern for complete information):
Science Ratings - Health Concerns
** - Asthma
** - Atherosclerosis
** - Colon cancer (reduces risk)
** - Depression
** - Dermatitis herpetiformis
** - Heart attack
** - HIV support
** - Immune function (for elderly people)
** - Infections (to prevent hospital-acquired infections in very low birth weight infants)
** - Infertility (male)
** - Lung cancer (reduces risk)
** - Lymphedema
** - Osgood-Schlatter disease
** - Pancreatic insufficiency
** - Phenylketonuria (if deficient)
** - Prostate cancer (reduces risk)
** - Rheumatoid arthritis
** - Thyroiditis (autoimmune)
* - Cardiac arrhythmia
* - Cardiomyopathy (only for Keshan’s cardiomyopathy)
* - Childhood diseases
* - Down’s syndrome
* - Halitosis (if gum disease)
* - Hepatitis
* - Hypothyroidism (if deficient)
* - Liver cirrhosis
* - Macular degeneration
* - Pap smear (abnormal)
* - Pre- and post-surgery health
* - Retinopathy (combined with vitamin A, vitamin C and vitamin E)
*** - Reliable and relatively consistent scientific data showing a substantial health benefit.

** - Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.

* - For an herb, supported by traditional use but minimal or no scientific evidence. For a supplement, little scientific support and/or minimal health benefit.
Who is likely to be deficient?
While most people probably don’t take in enough selenium, gross deficiencies are rare in Western countries. Soils in some areas are selenium-deficient and people who eat foods grown primarily on selenium-poor soils are at risk for deficiency. People with AIDS have been reported to be depleted in selenium.2 Similarly, limited research has reported an association between heart disease and depleted levels of selenium.3 People who are deficient in selenium have an increased risk of developing certain types of rheumatoid arthritis.4
How much is usually taken?
While the Recommended Dietary Allowance for most adults is 55 mcg per day, an adult intake of 100–200 mcg of selenium per day is recommended by many doctors.
Are there any side effects or interactions?
Selenium is safe at the level people typically supplement (100–200 mcg); however, taking more than 900 mcg of selenium per day has been reported to cause adverse effects in some people.5 Selenium toxicity can result in loss of fingernails, skin rash, and changes in the nervous system. In the presence of iodine-deficiency-induced goiter, selenium supplementation has been reported to exacerbate low thyroid function.6 Although most research suggests that selenium prevents cancer, one study found an increased risk of a type of skin cancer (squamous cell carcinoma) in people taking selenium supplements.7 The National Academy of Sciences recommends that selenium intake not exceed 400 mcg per day, unless the higher intake is monitored by a healthcare professional.8
Selenium enhances the antioxidant effect of vitamin E.

Drug Interactions
Certain medicines interact with selenium: Some interactions may increase the need for selenium (+), other interactions may be negative (-) and indicate selenium should not be taken without first speaking with your physician or pharmacist, others may require further explanation (?). Refer to the individual drug article for specific details about an interaction.
Note: The following list only includes the generic or class name of a medicine. To find a specific brand name, use the Medicines index.
Cisplatin (+)
Clozapine (+)
Cyclophosphamide (+)
Oral Corticosteroids (+)
Valproic Acid (?)
Source: www.cncahealth.com