Selenium is necessary for the production of some of the body’s most important proteins and enzymes, influencing everything from hormone balance to detoxification and immune system strength. Although you’re less likely to be deficient in selenium than in something like iron or vitamin B12, selenium deficiency does pose very real risks. However, you should never start taking selenium supplements without the express endorsement of your doctor – selenium toxicity is just as hazardous. That being said, here are nine warning signs of selenium deficiency you should not ignore at all cost.
1. Hypothyroidism Symptoms
Selenium is required to turn thyroxine (the thyroid hormone T4) into a more readily usable form. Consequently, if you aren’t getting enough selenium then you could begin to develop the main symptoms of hypothyroidism (which are more typically associated with a problem with the thyroid gland itself). In particular, you might gain weight, start to lose your hair, feel like your cognitive function is impaired, and suffer from breathlessness.
2. Certain Heart Problems
If you’re deficient in selenium and become infected with Coxsackievirus, you can develop a heart problem called Keshan disease. This condition weakens the heart muscle, and causes heart tissue to die off. Although Keshan disease has predominantly been seen in China, Finland and New Zealand, it’s another reminder of just how important it is to keep your selenium levels adequately high. There is also ongoing research into whether selenium deficiency is linked to cardiovascular disease more broadly, and some promising evidence that selenium supplements could help some heart disease patients.
3. Frequent Illness
Since your immune system relies on a steady supply of selenium, you should have your selenium levels tested if you seem to catch absolutely every bacterial and viral infection around. If you’re suffering from selenium deficiency, you may also experience more intense symptoms if you do get ill. So, if there’s a cold in your household and your family members are still functional yet you can barely get out of bed, take note.
4. Reduced Muscle Function
Your muscles may get weaker when your intake of selenium is too low, making it harder to carry heavy items or engage in workouts that you used to be able to tolerate without issue. Muscle wasting can also result from selenium deficiency, so you may start to see a difference in your body shape.
5. Reproductive Difficulties
Firstly, some recent research suggests that miscarriages are occasionally caused by very low levels of selenium, so it’s important to have a full blood profile ordered if you’re trying to figure out why your body is struggling to maintain a pregnancy. Secondly, the aforementioned hypothyroidism that can develop as a result of selenium deficiency can lead to heavier, irregular menstrual periods (which may then in turn also cause you to become deficient in iron). Further, there is a link between male infertility and selenium deficiency—for example, rats with selenium deficiency have greatly impaired sperm motility and deformed sperm.
6. Serious Gastrointestinal Disease
Although selenium deficiency doesn’t cause serious gastrointestinal problems, conditions like Crohn’s disease do put you at an increased risk of developing the deficiency. This is because these diseases leave your body struggling to properly absorb vital nutrients.
7. Fatigue
As with most vital nutrients, a lack of selenium can often leave you feeling more tired than usual. This sign is especially significant if seen in conjunction with the above symptoms of hypothyroidism, as an improper balance of thyroid hormones can also cause pervasive lethargy.
8. Older Age
Like significant gastrointestinal diseases, being over the age of 80 puts you at risk of selenium deficiency, most likely because your body is poorer at metabolizing dietary sources in older age. In addition, older people who don’t get enough selenium seem to be more likely to experience significant cognitive decline. The working hypothesis is that selenium’s status as an antioxidant means that it helps to maintain brain function. As such, there’s a possibility that selenium supplementation might eventually be recommended as part of an Alzheimer’s treatment program.
9. Cancer
Finally, another important reminder of why it’s so important to have an adequate intake of selenium is the growing body of research suggesting that selenium consumption is linked to a reduced risk of cancer – especially malignancies of the colon, lung, skin, esophagus and bladder. However, there’s a fine balance here. Unfortunately, too much selenium may actually cause certain forms of cancer. Adults should aim for 55mcg per day, increasing this to 60mcg per day during pregnancy.
These are the most importance warning signs of selenium deficiency that you should never take it lightly. If you’re interested in making sure that you have enough selenium in your diet, look to seafood and organ meats as some of the best sources. If you’re a vegetarian, you can focus on eggs, Brazil nuts, and grains.