High-selenium food products
High selenium pork: A successful product in Korea
- Selen pork, a special brand of high selenium pork, containing about ten times the selenium content of traditional pork is being marketed successfully in Korea. Pigs yielding this product are fed Sel-Plex, an organic selenium supplement which contains selenomethionine and other naturally-occurring organic selenium compounds
- A study performed in Spain reported that a combination of supplemental selenium and the antioxidant vitamins E and vitamin C in swine diets helped reduce drip loss and improve the shelf life of fresh pork products. Drip loss is a particular problem in pale, soft and exudative pork. Selenium and vitamins E and C are potent antioxidants. Vitamin E helps prevent lipids in the cell membrane from breaking down. Selenium also appears to protect the cell, preventing the fluid portion of the cytoplasm from breaking down (Munoz et al., 1997)
- In the study, University of Murcia researchers fed pigs 0.1 parts per million supplemental organic selenium. Pork from those pigs showed slightly lower drip loss for up to 120 hours after slaughter
- The organic forms of selenium are safer and these supplemental selenium sources are more bioavailable as compared to the inorganic forms
- In an additional trial, consumers rated the antioxidant-supplemented pork as juicier and more tender than pork from the control pigs that were not fed organic selenium (Munoz et al., 1997)
- Muscle pH impacts the effect of dietary selenium source in maintaining the meat quality
- Dietary organic selenium (SeY 0.3 mg/kg) supplementation improved the lipid stability, and color intensity in pig meat. The tenderness of the meat was maintained due to the decreased drip loss level with the increasing muscle pH (Calvo et al., 2016).
Selenium-rich designer eggs
- Efficient transfer of dietary selenium through the inclusion of an organic form of the trace element in laying hens’ diets opens up new possibilities for functional eggs providing this essential trace element to an increasingly health-conscious world population.
Selenium research highlights
- Selenium and prostate cancer
In a Harvard School of Public Health study, men with the greatest selenium intake had a two-thirds lower risk of developing advanced prostate cancer over the next decade than those with the lowest selenium intake
- A government-sponsored trial, one of the largest ever conducted, will begin late this year to test whether commonly used antioxidants vitamin E and selenium can prevent prostate cancer, as reported by Reuters. The 12-year “SELECT” study, to involve 32,400 men at about 300 research centers in the United States and Canada, will be the biggest prevention trial ever undertaken using a drug or nutrient, said Dr. Scott Lippman, chairman of clinical cancer prevention at M.D. Anderson Cancer Center in Houston
- Dr. Lippman said a large 10-year placebo-controlled U.S. trial began in 1983 to test whether a daily dose of 200 micrograms of selenium could prevent skin cancer. Although the supplementation did not have significant effects on the incidence of skin cancers, the incidence of prostate cancer, colorectal and lung cancers was significantly reduced in subjects taking the supplement as compared to those receiving the placebo. The role of selenium in cancer prevention might be due to its incorporation into one of the body’s most potent antioxidants, the enzyme glutathione peroxidase, as reported in several earlier studies
- A randomized double blind, placebo-controlled trial of selenium-enriched yeast (SY) (200 or 285 μg/day) and selenomethionine (SeMet) (200 μg/day) administered for 9 months in 69 healthy men showed reductions in the biomarkers of oxidative stress in SY supplemented individuals but not in SeMet supplemented group (Richie et al., 2014).
Selenium and immunity
- A new study on elderly subjects shows that micronutrient levels influence the number and function of natural killer (NK) cells – immune cells that defend the body against some tumor’s (Ravaglia et al., 2000). To explore the connection between micronutrients and NK cells, the researchers studied 62 Northern Italian men and women who lived independently and who ranged in age from 90 to 106 years. All were in good health, had normal blood test values, and were not taking nutritional supplements or medications that affect the immune system, such as anti-inflammatory drugs or hormones. All were apparently well nourished
- However, the investigators found that many of these individuals had micronutrient deficiencies. The most common deficiency, found in about 50% of both men and women, was in selenium, an essential mineral and antioxidant that protects the heart. Fifty-two percent of the men and 41% of the women were deficient in zinc, which plays a role in wound healing, proper growth, and immune system functioning. Deficiencies were also noted in vitamins A, E, B6, and folate (a type of vitamin B complex), as well as in ubiquinone-10, which is associated with cell functioning
- It was found that higher serum levels of selenium in women corresponded to greater NK-cell activity. In women, the defensive activity of the NK cells was greater when blood levels of vitamin E and ubiquinone-10 were higher. No other significant associations of micronutrients with NK cells were noted.
- High selenium yeast supplementation (200 μg/d) to 450 HIV-1 positive individuals for a period of 9 months showed suppression in the progression of HIV-1 viral burden, as well as provided indirect improvement of CD4 count (Hurwitz et al., 2007).
Selenium and mood
- Researchers from the University of Miami found that selenium therapy (in the form of the yeast supplement Selenomax) has a strong potential for improving the mental state and well-being of HIV-1 seropositive drug abusers. The one-month pilot study of selenium supplementation in such subjects revealed that Selenomax administration was associated with a decreased risk in the development of depressed-rejected mood state (Lead and Cocaine. 2000)
- Over 95% of the selenium in selenium yeast supplements such as Selenomax is present in the form of L-(+)-Selenomethionine (Lead and Cocaine. 2000)
- 50 subjects receiving either a placebo or 100 μg selenium daily showed reduction in the anxiety level with the elevation of individuals mood (Benton and Cook 1991).
Selenium deficiency may breed deadlier viruses
- According to a recent study, poor nutrition leads to mutations that create more dangerous forms of the influenza virus and may contribute to newly virulent outbreaks of viral epidemics ranging from the common cold to AIDS and Ebola hemorrhagic fever
- In selenium deficient mice, the human influenza virus mutated into more virulent forms. The authors of the study stated that a similar mutation of the virus is likely to occur in humans. In the study, groups of mice with normal and selenium-deficient diets were exposed to Influenza A Bangkok, a mild strain of human influenza virus. Although investigators had expected the malnourished mice to be sicker than the well-nourished ones, they confirmed that the virus also mutated to a greater degree in these mice. The research also confirmed earlier studies into the causes of mutations of a virus, Coxsackie B3, linked to a form of juvenile cardiomyopathy, Keshan disease (Beck et al., 2001)
- Selenium and polycystic ovary syndrome
A randomized, double-blind, placebo-controlled trial conducted among 70 women diagnosed with PCOS receiving 200 microgram per day selenium supplementation for 8 weeks showed beneficial effects on insulin metabolism parameters, triglycerides and VLDL-C levels (Jamilian et al., 2015)