Ben Kim on Jan 05, The authors of a Cochrane review concluded, based on nine randomized clinical trials, that selenium might help prevent gastrointestinal cancers but noted that these results need to be confirmed in more appropriately designed randomized clinical trials [ 38 ]. Your endocrine system includes eight major glands throughout your body. Omega-3 fatty acids found in fish oil are a healthy addition to any diet, especially for those looking to lose weight. N-Acetyl-Cysteine NAC is an antioxidant and amino acid that the body needs for overall endocrine health. Hormones are at the core of health—including sexual health.
In two large studies, participants with lower plasma selenium levels at baseline were more likely to experience cognitive decline over time, although whether the participants in these studies were selenium deficient is not clear [ 52 , 55 , 56 ].
An analysis of NHANES data on 4, elderly people in the United States found no association between serum selenium levels which ranged from lower than Researchers have evaluated whether taking an antioxidant supplement containing selenium reduces the risk of cognitive impairment in elderly people. MAX study on 4, participants aged 45 to 60 years in France found that, compared with placebo, daily supplementation with mg ascorbic acid, 30 mg vitamin E, 6 mg beta-carotene, mcg selenium, and 20 mg zinc for 8 years was associated with higher episodic memory and semantic fluency test scores 6 years after the study ended [ 58 ].
More evidence is required to determine whether selenium supplements might help prevent or treat cognitive decline in elderly people.
Selenium concentration is higher in the thyroid gland than in any other organ in the body, and, like iodine, selenium has important functions in thyroid hormone synthesis and metabolism. Epidemiological evidence supporting a relationship between selenium levels and thyroid gland function includes an analysis of data on 1, participants in the SU. MAX study indicating an inverse relationship between serum selenium concentrations and thyroid volume, risk of goiter, and risk of thyroid tissue damage in people with mild iodine deficiency [ 59 ].
However, these results were statistically significant only in women. A cross-sectional study in adults with mild iodine deficiency in Denmark also found a significant inverse association between serum selenium concentration and thyroid volume in women [ 60 ]. Randomized, controlled trials of selenium supplementation in patients with thyroid disease have had varied results. Compared with patients treated with placebo, those treated with selenium but not pentoxifylline reported a higher quality of life.
Women with thyroid peroxidase antibodies tend to develop hypothyroxinemia while they are pregnant and thyroid dysfunction and hypothyroidism after giving birth [ 9 ]. The authors of a Cochrane review of hypothyroidism interventions during pregnancy concluded, based on a trial that administered supplements containing mcg selenium as selenomethionine daily to pregnant women with thyroid peroxidase antibodies [ 63 ], that selenomethionine supplementation in this population is a promising strategy, especially for reducing postpartum thyroiditis [ 64 ].
However, the authors called for large randomized clinical trials to provide high-quality evidence of this effect.
Additional research is needed to determine whether selenium supplements can help prevent or treat thyroid disease. Chronically high intakes of the organic and inorganic forms of selenium have similar effects [ 6 ]. Early indicators of excess intake are a garlic odor in the breath and a metallic taste in the mouth. The most common clinical signs of chronically high selenium intakes, or selenosis, are hair and nail loss or brittleness.
Other symptoms include lesions of the skin and nervous system, nausea, diarrhea, skin rashes, mottled teeth, fatigue, irritability, and nervous system abnormalities. As discussed earlier, Brazil nuts contain very high amounts of selenium 68—91 mcg per nut and could cause selenium toxicity if consumed regularly. Acute selenium toxicity has resulted from the ingestion of misformulated over-the-counter products containing very large amounts of selenium [ 2 , 5 ].
In , for example, people experienced severe adverse reactions from taking a liquid dietary supplement containing times the labeled amount [ 65 ]. Acute selenium toxicity can cause severe gastrointestinal and neurological symptoms, acute respiratory distress syndrome, myocardial infarction, hair loss, muscle tenderness, tremors, lightheadedness, facial flushing, kidney failure, cardiac failure, and, in rare cases, death [ 2 , 6 ]. The FNB has established ULs for selenium from food and supplements based on the amounts of selenium that are associated with hair and nail brittleness and loss see Table 3 [ 6 ].
Selenium can interact with certain medications, and some medications can have an adverse effect on selenium levels. One example is provided below. Individuals taking this and other medications on a regular basis should discuss their selenium status with their healthcare providers. Cisplatin, an inorganic platinum chemotherapy agent, is used to treat ovarian, bladder, lung, and other cancers.
Cisplatin can reduce selenium levels in hair and serum but whether these reductions have a clinically significant impact is not known [ 66 , 67 ]. The federal government's Dietary Guidelines for Americans notes that "Nutritional needs should be met primarily from foods.
Foods in nutrient-dense forms contain essential vitamins and minerals and also dietary fiber and other naturally occurring substances that may have positive health effects. In some cases, fortified foods and dietary supplements may be useful in providing one or more nutrients that otherwise may be consumed in less-than-recommended amounts.
For more information about building a healthy diet, refer to the Dietary Guidelines for Americans and the U. Department of Agriculture's MyPlate. This fact sheet by the Office of Dietary Supplements ODS provides information that should not take the place of medical advice.
We encourage you to talk to your healthcare providers doctor, registered dietitian, pharmacist, etc. Any mention in this publication of a specific product or service, or recommendation from an organization or professional society, does not represent an endorsement by ODS of that product, service, or expert advice. March 2, History of changes to this fact sheet. Strengthening Knowledge and Understanding of Dietary Supplements.
Selenium Fact Sheet for Health Professionals. Modern Nutrition in Health and Disease. Bowman B, Russell R, eds. Present Knowledge in Nutrition. International Life Sciences Institute; Selenium supplementation and cancer prevention. Curr Nutr Rep ;1: Encyclopedia of Dietary Supplements. London and New York: Estimation of antioxidant intakes from diet and supplements in U.
Food-chain selenium and human health: Br J Nutr ; Selenium and human health. Department of Agriculture, Agricultural Research Service. Am J Clin Nutr. Preparation, homogeneity and stability studies of a candidate LRM for Se speciation. Effects of chemical form of selenium on plasma biomarkers in a high-dose human supplementation trial.
Cancer Epidemiol Biomarkers Prev ; Dietary supplement use in the United States, Serum selenium and serum lipids in US adults: Distribution of toenail selenium levels in young adult Caucasians and African Americans in the United States: Serum selenium levels in the US population: Biol Trace Elem Res ; Sex, age, geographical location, smoking, and alcohol consumption influence serum selenium concentrations in the USA: J Trace Elem Med Biol ; Asia Pac J Clin Nutr ; Sodium selenite for treatment of Kashin-Beck disease in children: Vitamin and Mineral Requirements in Human Nutrition.
Trace elements in hemodialysis patients: Role of selenium in HIV infection. High risk of HIV-related mortality is associated with selenium deficiency. Curr HIV Res ;5: Mortality risk in selenium-deficient HIV-positive children. Selenium levels in relation to morbidity and mortality among children born to HIV-infected mothers.
Eur J Clin Nutr ; Selenium status, pregnancy outcomes, and mother-to-child transmission of HIV J Acquir Immune Defic Syndr ; Impact of a selenium chemoprevention clinical trial on hospital admissions of HIV-infected participants. HIV Clin Trials ;3: Suppression of human immunodeficiency virus type 1 viral load with selenium supplementation: Arch Intern Med ; Randomized, double-blind, placebo-controlled trial of selenium supplements among HIV-infected pregnant women in Tanzania: Am J Clin Nutr ; Effect of selenium supplements on hemoglobin concentration and morbidity among HIVinfected Tanzanian women.
Clin Infect Dis ; Plasma selenium concentration and prostate cancer risk: Pharmacol Ther ; Selenium for preventing cancer. Cochrane Database Syst Rev Are men with low selenium levels at increased risk of prostate cancer? Eur J Cancer ; Aliment Pharmacol Ther ; Selenium supplementation, baseline plasma selenium status and incidence of prostate cancer: The effect of selenium and vitamin E on risk of prostate cancer and other cancers: Klein EA, Thompson Jr.
Vitamin E and the risk of prostate cancer: Food and Drug Administration. Selenium and coronary heart disease: Longitudinal association between toenail selenium levels and measures of subclinical atherosclerosis: Serum selenium levels and all-cause, cancer, and cardiovascular mortality among US adults.
Serum selenium and peripheral arterial disease: Am J Epidemiol ; Effect of supplementation with high-selenium yeast on plasma lipids: Ann Intern Med ; Incidence of cancers, ischemic cardiovascular diseases and mortality during 5-year follow-up after stopping antioxidant vitamins and minerals supplements: Int J Cancer ; Effects of selenium supplementation on cardiovascular disease incidence and mortality: Selenium supplementation for the primary prevention of cardiovascular disease.
Cochrane Database Syst Rev. Hormones are chemical messengers. They travel through your bloodstream to tissues or organs. Hormones work slowly and affect body processes from head to toe.
If your hormone levels are too high or too low, you may have a hormone disorder. Hormone diseases also occur if your body does not respond to hormones the way it is supposed to. Stress, infection and changes in your blood's fluid and electrolyte balance can also influence hormone levels. In the United States, the most common endocrine disease is diabetes.
There are many others. They are usually treated by controlling how much hormone your body makes. Hormone supplements can help if the problem is too little of a hormone.
On this page Basics Summary Start Here. See, Play and Learn Videos and Tutorials.