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Odds Are You Suffer From One of These Nutritional Deficiencies

Written by Randa Laouar, BS (Biochemistry & Physiology) | Reviewed by Biljana Novkovic, PhD | Last updated:
Jonathan Ritter
Medically reviewed by
Jonathan Ritter, PharmD, PhD (Pharmacology) | Written by Randa Laouar, BS (Biochemistry & Physiology) | Reviewed by Biljana Novkovic, PhD | Last updated:

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Even if you eat a healthy diet, you may still fall short of essential vitamins & minerals. Learn about the common nutrient deficiencies & how to avoid them.

What are Nutritional Deficiencies?

Ever wonder if you have a vitamin or mineral deficiency? Chances are, you do.

Sure, you may eat a sufficient amount of food, and perhaps more than you need to. You probably do get your fair share of fruits and vegetables. But there is a good chance you’re not getting enough nutrients.

Sounds a little extreme? Well, according to a study that analyzed 4 popular diet plans, even people who eat five daily servings of fruits and vegetables may not get enough of certain vitamins for optimal health. Most people, for instance, cannot get the healthiest levels of folate and vitamins D and E from recommended diets [1].  

Another study found that out of 20 individuals, including both athletes and sedentary people, all of them had at least two or more nutrient deficiencies, the most common being iodine, vitamin D, zinc, calcium, and vitamin E [2].

Bottom line: It is difficult, even for the healthiest of eaters, to get all of the essential vitamins and minerals solely from the diet [3].

Why does this happen? Firstly, how and where your food was grown influences its nutritional content. Studies show that the nutritional quality of food has declined over the years due to modern day agricultural practices [2, 4].

And if you are older, have digestive problems, take certain medications, or drink coffee or tea, you likely will not absorb many of these nutrients altogether [5].

Why does this matter? Because even minor deficiencies of critical vitamins and minerals can have harmful effects. They can damage your DNA, accelerate aging, and increase your risk of becoming overweight and obese. They are the common culprit behind many chronic diseases, contributing to heart disease, osteoporosis, and cancer [1, 6].

Below is a list of the most common nutritional deficiencies. The good news is that it’s easy to remedy these issues and get yourself back on track towards optimal health!

Nutrients You May Be Low On

1. Iron

When it comes to common nutritional disorders, iron deficiency takes the cake. It is estimated to affect more than a quarter of people worldwide [7, 8, 9]!

You are more likely to have an iron deficiency if you are a woman, thanks to blood loss during menstruation. Pregnant women and children are also at risk due to their increased need for iron [10].  

Iron is found in all of your cells. One of its main roles is to transport oxygen in the hemoglobin of red blood cells to tissues [10].

Iron is also required for [11, 12, 13, 14, 15, 16]:

  • Red blood cell production
  • Energy production in the heart and muscles
  • Brain development and normal brain function
  • Immune system development and immune response
  • Resistance to infections
  • Production and degradation of DNA

Given these important roles, it’s not surprising that even a mild iron deficiency can result in anemia, fatigue, headaches, pale skin, anxiety, infection, shortness of breath, and a greater risk of death overall [17, 18, 19, 20, 21, 22, 23].

You should test your iron levels by doing the following blood tests:

  • Iron. Although iron is commonly tested, blood iron may not be the best measure of your overall iron content because it fluctuates. It can increase after an iron-rich meal for example [24, 25]. That is why this test is often run together with TIBC, UIBC.
  • TIBC (Total iron binding capacity). This test measures proteins in the blood, including transferrin, which is available to bind iron. It can be measured together with iron, to give a better indication of iron deficiency.
  • UIBC (Unsaturated iron binding capacity). This test measures the “reserve capacity” of transferrin or the amount of transferrin that has not yet been saturated with iron.
  • Transferrin saturation – is the percentage of transferrin that is saturated with iron. This value is derived from your iron and TIBC levels.
  • Ferritin. This protein is usually a good measure of your body’s total iron stores. It can be unreliable if you have an infection, chronic inflammation, liver, kidney, or other diseases [26].

It is important to test your iron levels before you start taking supplements or increase your dietary iron intake. Too much iron can be dangerous, as it can build up in the body and cause cell damage [27]! That’s why you should take iron supplements only after exhausting dietary options and consulting with your doctor.    

If your iron levels are suboptimal or low, you can boost your dietary intake by increasing red meat, poultry, fish, beans, and green leafy vegetables such as broccoli, kale, and spinach. These are all rich in iron [28].

Avoid milk, caffeine, calcium, or antacids, as these can reduce iron absorption. Taking vitamin C with iron-rich foods, on the other hand, increases iron absorption [29, 30, 31, 32, 33, 34, 35, 36].

2. Calcium

Calcium is essential for every cell. Its main function is to support the structure and function of your skeleton. More than 99% of your calcium is stored in your bones and your teeth! The rest of the calcium in your body is used for other critical processes such as muscle contraction, blood clotting, and the transmission of nerve signals [37].

Even though it’s one of the most vital minerals for your health, many people are still not getting enough calcium in their diet. In fact, one study suggests that nearly 68% of the American population is calcium deficient [38].

Calcium deficiency symptoms vary widely – ranging from nonexistent or mild to severe and life-threatening. In some cases, you may experience tingling in the fingers and toes and muscle cramping. Left untreated, calcium deficiency can lead to bone disease (e.g. rickets, osteopenia, and osteoporosis) [39, 40].

You can check your calcium levels by doing a simple blood test.

Thankfully, calcium deficiency is relatively easy to treat. It typically involves adding more calcium to your diet. Calcium-rich foods include green leafy vegetables and dairy products [37].

Foods that bind calcium, such as spinach, potatoes, rhubarb, and beets can reduce calcium absorption, so its best to avoid them if your calcium levels are low or suboptimal [41].

Calcium supplements may also benefit people who are not getting enough of this mineral in their diet [42].

3. Vitamin B12

Vitamin B12 is often touted as the “energy vitamin” because of its role in energy metabolism. It helps make DNA, nerve and blood cells and is essential for a healthy brain and immune system [43].

Vitamin B12 is only found in animal products like eggs, meat, shellfish, and dairy. Around 14-16% of people don’t get enough B12, and they’re more likely to be [44, 45, 46, 47, 48]:

  • Vegetarians or vegans
  • Suffering from the celiac disease or other digestion problems
  • Over 50 (as we get older, our ability to absorb nutrients decreases).

Sometimes, it’s easy to miss a deficiency of vitamin B12 because it can take years before you have symptoms. As the condition worsens, common symptoms include brain fog, fatigue, apathy, mood swings, memory problems, muscle weakness, and tingling in the arms and legs. That is why it is critical that you get your levels checked before complications occur [49].

You can check your vitamin B12 levels by doing a total vitamin B12 blood tests. You can also test your active vitamin B12 levels. However, this second test is more expensive, and studies show it may not do a better job at scanning for vitamin B12 deficiency compared to a total vitamin B12 test [50, 51].

If your levels are low or suboptimal, you can increase them by consuming more vitamin B12-rich foods or taking supplements. Good sources include red meat, fish, poultry, yogurt, and milk. Vitamin B12 is poorly absorbed from eggs [52, 53, 54].

Avoid smoking and alcohol. Both decrease vitamin B12 levels [55, 56, 57, 58]

4. Vitamin E

Vitamin E is an important antioxidant that protects your cells from free radicals — byproducts of oxidative stress [59].

One-fifth of the world’s population and at least 75 percent of Americans are deficient in vitamin E. If you are one of them, you have a higher risk for depression, heart disease, cognitive decline, and immune dysfunction [60, 61, 62, 63].

You can check your vitamin E levels by doing an alpha-tocopherol and a gamma-tocopherol blood test. These are two major forms of vitamin E.

If you have a deficiency, don’t fret! The solution is simple: eat plenty of vitamin E rich foods and take a naturally-derived vitamin E supplement if necessary. Vitamin E rich foods include [64, 65, 59]:

  • Oils (wheat germ, sunflower, hazelnut, almond, cottonseed, safflower, etc.)
  • Sunflower seeds
  • Almonds
  • Hazelnuts
  • Peanut butter
  • Avocadoes
  • Spinach
  • Broccoli
  • Kiwi

Your gut needs fat to absorb vitamin E, so make sure you consume enough healthy fats in your diet (e.g. olive oil, nuts, avocados) when taking supplements [66].

Opt for a supplement that contains multiple forms of vitamin E (e.g. both alpha-tocopherol, gamma-tocopherol). Some earlier studies suggested that megadoses of vitamin E supplements may be harmful [67]. However, more recent and larger studies show no negative effects with very high supplement doses [68].

5. Magnesium

Magnesium is the 4th most abundant mineral in the body. It is required for more than 300 different bodily processes. Because of this, a deficiency can wreak havoc on your health. Your body needs magnesium for [69, 70, 71, 69]:

  • Activating muscles and nerves
  • Energy production
  • Making DNA
  • Activating vitamin D and B-vitamins

An estimated 75% of the U.S. population does not meet the recommended dietary allowance of magnesium [72].

Low levels are marked by loss of appetite, fatigue, nausea, insomnia, irritability, and muscle weakness. In its worst stages, magnesium deficiency can lead to osteoporosis, heart disease, high blood pressure, and diabetes [73, 74, 75, 75, 75, 76, 77, 76, 70, 78].  

Magnesium is another nutrient that is easy to test. If your levels are suboptimal or low, increase the intake of magnesium-rich foods or take supplements.

If you’re not including lots of dark green leafy vegetables, avocados, nuts, and seeds in your diet, start right now [79, 80, 81, 79, 80, 81]. Other magnesium-rich foods include:

  • Whole (unprocessed) grains [81, 79, 80]
  • Beans [82]
  • Nuts (such as almonds and cashews)
  • Legumes (especially soy) [83, 79, 80]
  • Fruits [83, 79, 80]
  • Red meat [83, 79, 80]
  • Fish/seafood [83, 79, 80]

6. Vitamin D

Around 42% of adults in the U.S. are deficient in the “sunshine vitamin”, vitamin D. Low levels are increasingly linked to everything from cancer and heart disease to autoimmune disease [84, 85].  

Vitamin D helps maintain healthy levels of calcium and phosphorus by increasing their absorption in the gut. In this way, vitamin D is critical for the proper growth and formation of bones [86, 87].

It also plays a role in muscle strength and performance, immune system function, blood pressure, and insulin secretion [87, 88, 89, 90].

Vitamin D is produced by the skin upon exposure to sunlight. It can also be obtained in the diet, or through vitamin supplements [91].

One of the major causes of low vitamin D levels is insufficient exposure to UVB radiation from the sun, which prevents the skin from being able to produce enough vitamin D. Specific risk factors include:

  • Living at high latitudes (>37°) [92, 93, 94]
  • Living in regions where there are large seasonal changes in sun exposure [95]
  • Living in areas with high levels of air pollution, which blocks out sunlight [96]
  • Over-use of sunscreen [97]
  • Having darker skin [98, 99]
  • Keeping the skin covered up (in colder climates or certain cultures) [100, 101]

Symptoms of vitamin D deficiency are not always obvious and can take years to manifest. Some signs may include fatigue, muscle weakness, bone loss, and depression [102].

If you are experiencing any of these symptoms, you should get your vitamin D level tested ASAP. 25-hydroxyvitamin D is one of the most commonly tested vitamin D forms.

You can use Lab Test Analyzer to learn if your vitamin D levels are optimal. High doses of vitamin D supplements can be toxic, so it’s important to keep track of your levels if you choose to supplement.

Getting enough of vitamin D from food can be tricky—cod liver, fatty fish such as salmon and sardines, egg yolk, and mushrooms are the only good natural sources. However, a lot of other foods are now fortified with this vitamin. If supplementing, choose vitamin D3 (cholecalciferol), the form your body naturally makes when it’s exposed to sunlight [103, 104, 105].

7. Zinc

Zinc is an essential mineral found in all organs, tissues, and fluids in the body [106].

As the second most abundant trace mineral in the body after iron, it plays a crucial role in a variety of biological processes [107, 108].

Zinc is required for the activity of more than 300 enzymes involved in the metabolism of carbohydrates, fats, proteins, nucleic acids, and other micronutrients [109].

It also plays roles in stabilizing cell and organ structures, immune function, wound healing, cell division, growth, blood clotting, thyroid function, vision, taste, and smell [110].

Given zinc’s many key roles, it’s alarming that around 31% of the world’s population is deficient in this mineral [111]

You are at risk for zinc deficiency if you [112, 113]:

  • have digestive disorders
  • are vegetarian
  • are pregnant and lactating
  • are an alcoholic
  • have sickle cell disease

Because zinc plays such critical roles in your body, symptoms of a deficiency can show up in a variety of ways. Some of the more common symptoms include diarrhea, infections, hair loss, eye, and skin conditions, delayed wound healing, impotence, and loss of appetite [114].

If you suspect that you have a zinc deficiency, check your levels by taking a blood or urine test.

Increase your intake of zinc from foods or supplements, if you are deficient. Good dietary sources of zinc include red meats, seafood, dairy products, nuts, legumes, and whole grains [115].

8. Iodine

Do you suffer from dry mouth, dry skin, lack of sweating, an enlarged thyroid gland, rapid heart rate, shortness of breath, and weight gain? If so, you may have an iodine deficiency [116, 117, 118, 119].

Approximately one-third of the world’s population is iodine deficient [120, 121, 122].

Iodine is an essential mineral found in all of your organs and tissues. Your body needs iodine for normal thyroid function, including the production of thyroid hormones, which support brain development, bone maintenance, growth and metabolism [117, 123].

The easiest way to check your iodine levels is to do a urine iodine test. This test measures your recent iodine intake. For chronic iodine deficiency (or overload) it is useful to also check your thyroid function (e.g. TSH, free T4, free T3).

If you are low in iodine, increase your intake of eggs, fish, meat, cereals, green vegetables, spinach, and seaweed (kelp, kombu, nori, and wakame) [124, 116].

You can also use more iodized salt to season your food (unless you have to restrict the amount of salt in your diet for health reasons) [125].

If you decide to take an iodine supplement, be aware of the potentially serious risks associated with excess iodine, and monitor your iodine levels and thyroid function [126].

Irregular Nutrient Levels?

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About the Author

Randa Laouar

BS (Biochemistry & Physiology)

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