Selenium source foods include meat, vegetables, and legumes. The amount of selenium found in food depends on the level of selenium from the soil in which it grows.
Selenium is found in an enzyme called glutathione peroxidase that acts as an antioxidant. However, in high quantities, selenium can act as a pro-oxidant (a substance that can make oxygen byproducts that can damage cells).
Over selenium can play a role in many diseases, including cancer. Research on animals and populations has suggested that selenium diet supplementation may reduce cancer risk.
The results of the NPC (Nutritional Prevention of Cancer) study showed that, although the selenium diet did not affect the risk of skin cancer, it decreased the risk of lung, colorectal, and prostate cancer.
However, research on how the level of selenium in the blood affects the risk of developing prostate cancer has shown mixed results.
The study cautions caution against the use of selenium supplements between men and prostate cancer, and other studies have concluded that men should avoid selenium supplementation at higher doses of recommended dietary intake.
Clinical trials of prostate cancer prevention with selenium diet
A study in rats aimed to see the effects of selenium dietary prostate cancer prevention began at different ages.
Adult rats and young rats were fed enriched selenium diet and diet without selenium for 6 months or 4 weeks and then injected with prostate cancer cells.
Adult rats with selenium in food, they developed fewer secondary tumors than adult rats with non selenium diets. However, in young mice, selenium in the diet has no effect on tumor development.
Strain mice with prostate cancer are treated like human cancers and treated with 2 forms of selenium, MSeA and methylselenocysteine (msec), or water alone.
In selenium-treated mice, the growth of precancerous lesions is slowed and cancer cell death increases compared with mice treated with water alone.
Clinical trials of prostate cancer treatment
Clinical trials of selenium effects on prostate-specific antigen (PSA) levels or prostate cancer progression have shown mixed results, including the following:
In a study reported in 2013, men at high risk of prostate cancer were given a daily high dose of selenium yeast (200 mg or 400 mg) and placebo for up to 5 years.
As a result, there was no difference in prostate cancer or PSA rates in men taking selenium supplements compared with those taking only placebo.
Another study involving 4,459 people was diagnosed with prostate cancer that has not spread. The study found that taking selenium supplements (140 or more ug / day) after diagnosis could increase the risk of death from prostate cancer and recommended that men with prostate cancer use caution in taking selenium supplements.
Combination of Selenium and Vitamin E
This is a major clinical trial started by the National Institutes of Health in 2001 to study the effects of selenium and / or vitamin E on the development of prostate cancer. More than 35,000 men, aged 50 years and older, were randomly assigned to receive one of the following combinations daily for 7-12 years:
- Vitamin E (alpha-tocopherol acetate, 400 IU / day) and placebo;
- Selenium (L-selenomethionine, 200 mcg / day) and placebo;
- Vitamin E and selenium
Recent results in 2011 showed that selenium supplement diet had little effect on prostate cancer risk. However, men taking vitamin E alone had a 17 percent increased risk of prostate cancer.
Several factors may affect the results of the study, including the dose of vitamin E selected and the selenium form used.
The authors concluded that men should avoid selenium supplementation at high doses rather than the recommended dietary intake.
How many selenium doses in prostate cancer diet?
Selenium can be consumed in diet or taken in dietary supplements. For adults, the recommended daily allowance for selenium is no more than 55 mg / day. Various forms of selenium have been shown to slow the growth and spread of prostate cancer cells.
Side effects of the selenium diet
Selenium supplements have been tolerated in many clinical trials. Patients are monitored and given a certain dosage in clinical trials. In several published trials, no differences were reported regarding adverse events.
However, the use of selenium supplements (200 mg daily) was associated with a slightly increased risk of diabetes mellitus. The FDA has not yet approved the use of selenium supplements for the treatment or prevention of prostate cancer or other medical conditions.
Source : http://www.webmd.com/prostate-cancer
