Selenium Health Benefits

Selenium could very well be one of the most important nutrients or supplements that you consume as part of your daily diet. It offers a multitude of health benefits to the body such as protecting against cancer, slowing down the aging process and improving thyroid function. Selenium is also very beneficial for promoting cardiovascular health, as was vividly shown by residents living in the Keshan district in northeast China.

Scientists noted that a large number of young men in this region were dying of cardiomyopathy, a type of heart disease that affects the integrity of cardiac muscle and can result in sudden cardiac death. It was later discovered that the Keshan district, as well as a very narrow strip of land running south below it, contained extremely low levels of selenium in the soil.

To see if a selenium deficiency was in fact responsible for causing these deaths, researchers took a sample of men and gave one half selenium supplements and the other half a placebo. After six months the difference between the two groups was so great that the study had to be abandoned, and all men were given selenium supplements to take.

Why Is Selenium Important?

Selenium is a trace mineral that is naturally found in soil, although the concentrations at which it is found can vary considerably depending on where in the world you live.

As with all trace minerals, you only need very small amounts to obtain health benefits. In the case of selenium, this will involve taking a dosage that is measured in micrograms (µg or mcg). In contrast, when you take a vitamin, such as vitamin C, you will be taking a dosage that is measured in milligrams or grams (mg or g).

Because you only need trace minerals in very small amounts, a true deficiency in one particular mineral tends to be relatively rare. This is especially true for people living in western countries where there is a wide variety of foods to eat that are flown in from many different parts of the world.

However, as you previously saw in the Keshan district study, it is possible for soils to be deficient in minerals. Unfortunately, this has increasingly become the case since the agricultural revolution, where people began to farm intensively in order to provide food for a rapidly growing population.

Today, much of the food that we eat is grown on mineral depleted soils. They may not be completely devoid of minerals, but the level of minerals that they do contain is generally so low that our food has become much less nutritious than it was even 50 years ago.

So although the foods that you buy in your local grocery store may help you to prevent deficiencies in certain minerals, most will probably do very little for improving your overall level of health. This is why many health conscious people are choosing to supplement with minerals such as selenium, as by doing so, they can help to compensate for the lack of nutrition that commercial foods contain.

In the rest of this article, we shall be looking specifically at the health benefits that the trace mineral selenium can provide the body with. But in order to fully understand these benefits, we first discuss the biological roles that it plays within the body. Please feel free to skip this section if you just want to go directly to the list of benefits.

Antioxidant

One of the most important roles that selenium plays within the body, is in helping to protect against the harmful effects of free radicals. These occur as a by-product of oxidation reactions, and have been linked to many of the major diseases that people suffer from such as cardiovascular disease, cancer and degenerative brain disorders like Alzheimer’s disease.

In general, it is believed that the more free radicals a person is exposed to, the more likely they are to suffer from ill health. As a result, if one wishes to obtain optimal levels of health, then it necessary to take steps to prevent or minimize the damage that these free radical cause. One way in which you can do this is with antioxidants.

An antioxidant is something that stops or slows down the oxidation of other molecules, and by doing so, also stops or slows down the amount of free radicals that are produced as a result of that oxidation reaction. In general, there are two main types of antioxidants.

The first, are water soluble antioxidants such as vitamin C, and these help to protect the body against free radicals largely by binding to already existing free radicals and neutralizing them so that they cannot do any further damage.

The second type of antioxidant are the fat soluble antioxidants, such as vitamin E, and these help to protect against free radical damage by preventing the oxidation of fats in the body, such as the lipids found in cell membranes.

Both of these types of antioxidants come from exogenous sources. This means that in order to benefit from the protection that they provide, you must consume foods, or take supplements, that contain antioxidants such as vitamin C or vitamin E.

Selenium also works as an antioxidant but in a slightly different manner, as it is used by the body to produce an extremely powerful endogenous antioxidant known as glutathione peroxidase, a type of selenoprotein.

Interestingly, the levels of glutathione decrease by about 10% per decade once you pass the age of 25, and this is also roughly the time when a person starts to look older and become more susceptible to ill health and disease.

Many scientists and doctors believe that if you are able to maintain adequate levels of antioxidants in the body, then you will be able to protect yourself against such negative effects by slowing down the aging process.

Cancer

Cancer can occur due to many different reasons, although its ultimate cause occurs due to deoxyribonucleic acid (DNA) damage which subsequently causes cells to function abnormally or undergo uncontrolled cell division.

Many studies have shown that there tends to be a reduced risk of cancer with selenium intake, suggesting that this mineral plays an important role in helping the cells of the body to function normally.

Selenium seems to protect the body from cancer in a variety of different ways. It can for example, promote the repair of damaged DNA, stop cancer cells from growing out of control and induce programed cell death, or apoptosis, of already cancerous cells.

In addition, the enzyme glutathione peroxidase also assists in the detoxification of harmful substances from the body and helps to prevent the oxidation of cell membranes, which, in turn, helps to protect the cells themselves and the cellular contents that they contain.

Finally, selenium also helps to increase the strength of the immune system by stimulating the production of white blood cells, or leukocytes, which some believe play a role in helping the body to clear out cancerous cells as well as destroying invading pathogens.

Selenium appears to be such a powerful protector against cancer, that one study, conducted by Cornell University and the University of Arizona, found that cancer patients who took selenium supplements had around 60% fewer prostate and colorectal tumors, around 50% fewer lung malignancies and a 40% overall decrease in death rates than the cancer patients who were not taking selenium supplements.

Other studies have shown selenium to be beneficial for many other types of cancers such as cancer of the bladder, cancer of the pancreas, cancer of the oesophagus, cancer of the breast and cancer of the liver.

Overall, the general findings of such studies seem to indicate that those who do take selenium supplements are less likely to die from cancer, less likely to have their cancer metastasize to other parts of the body and are less likely to have their cancer reappear after it has been successfully treated.

Cardiovascular

At the beginning of this article we gave an example of how important selenium can be in helping to prevent cardiovascular disease. To recap, a small stretch of land in China was found to have unusually high rates of heart disease in young men as a result of selenium deficient soil, and that these deaths were successfully lowered with selenium supplementation. So clearly, selenium does appear to play a very significant role in helping to maintain a healthy heart.

But just like with cancer, the exact reasons for why selenium seems to protect the cardiovascular system are not known for certain, although it is believed that the benefits selenium offers come as a result of its ability to prevent the oxidation of cholesterol deposits in the arteries, lower levels of bad, or low-density lipoprotein (LDL) cholesterol and reduce how sticky the blood is so that there is less chance of it clotting and blocking the supply of blood to other regions of the body.

What Are The Health Benefits Of Selenium?

The health benefits of selenium largely occur as a result of its ability to protect cells and genetic material from free radical damage, and from its ability to assist the body in the detoxification of harmful substances as has just been discussed in the previous section. The following list provides a summary of the main health benefits that have been associated with selenium intake.

• Reduces the risk of contracting many forms of cancer.

• Helps to promote heart and cardiovascular health.

• Needed for glutathione peroxidase production which protects the body against free radical damage.

• Protects eye health and protects against age related macular degeneration.

• Can reduce levels of inflammation within the body.

• Can reduce symptoms of asthma.

• May help to protect against developing rheumatoid arthritis.

• Low levels of selenium may play a role in depression.

• Selenium containing shampoos may reduce dandruff.

• Works synergistically with vitamin C and vitamin E.

• Lowers LDL cholesterol.

• Boosts immune function and resistance against pathogens and disease.

• Helps to detoxify the body of harmful substances such as heavy metals.

• Helps to promote fertility.

• Protects against DNA damage.

• Important for normal functioning of the thyroid gland.

• Helps to promote healthy blood sugar levels.

• Helps to slow down the aging process.

• Has powerful anti-viral capabilities.

• Protects the skin against sun damage which can cause premature skin aging and wrinkles.

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How Much Do You Need?

The recommended daily allowance (RDA) for selenium is 55 mcg for women and 70 mcg for men. However, some studies show that you need at least 130 mcg to gain the anti-cancer benefits that selenium provides.

Most supplements purchased in health food stores will supply 200 mcg of selenium per tablet or capsule.

Where Do You Get It?

The amount of selenium that you receive from food largely depends upon the level of selenium found in the soil from which the food was grown. However, since most soils tend to have quite low levels of selenium, most foods also contain low levels of selenium. A notable exception to this are Brazil nuts which provide around 1917 mcg of selenium per 100g.

Other food sources that can be high in selenium are nuts, fish, grains, seafood and yeast.

It should be noted that a true selenium deficiency in western countries is quite rare. The reason for this is because people in western countries eat a variety of foods from across the world, and so they also consume differing levels of selenium which may compensate for low levels found in one particular type of food or low levels found in foods from a particular world region.

People most at risk of suffering from a deficiency, are those who eat predominantly locally grown foods that are grown in selenium depleted soils.

Who Needs Selenium Vitamin Supplements?

Since the amount of selenium that you are likely to get from your diet is relatively low, virtually everyone would benefit from taking a high quality yeast based organic selenium supplement. 200 mcg is recommended.

It is important to remember that selenium is only required in trace amounts, so taking more isn’t necessarily a good thing. In fact, too much selenium can result in selenosis which can then cause symptoms such as hair loss, fatigue and even nerve damage.

If you do want to take a higher dose than 200 mcg, you can go up to 400 mcg quite safely and possibly up to 600 mcg. But for most people who are in general good health, 200 mcg should be sufficient.

To obtain the maximum health benefits from selenium supplementation, take it with vitamin E, as the two nutrients work synergistically together. If you do not want to purchase supplements, eat a handful of Brazil nuts each day and you will be getting a good level of selenium intake.

At present, L-Se-Methylselenocysteine seems to be one of the better forms of selenium found in supplements.

Signs Of Deficiency

Some of the main signs of a selenium deficiency are:

• Infertility
• Prostate problems
• Heart disease
• Cancer
• Muscle pain

Best Food Sources

The best foods to get selenium naturally from your diet are:

• Brazil nuts
• Steak & kidney pie
• Oily fish
• Tuna
• Nuts
• Shrimps
• Wholemeal bread
• Sunflower seeds
• Mushrooms
• Liver
• Brewers yeast