Warning Lights: Common Symptoms of Nutrient Deficiencies

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The Pure TheraPro Team

The Pure TheraPro Education Team is comprised of researchers from diverse backgrounds including nutrition, functional medicine, fitness, supplement formulation & food science. All articles have been reviewed for content, accuracy, and compliance by a holistic integrative nutritionist certified by an accredited institution.
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When your car needs an oil change, is low on brake fluid or needs air in the tires, it signals you with warning lights. Your body does the same thing—with symptoms. Symptoms are warning lights that your body needs something—and if you are aware of what they’re telling you, it may save your health!

Here are some common symptoms that appear when you have a vitamin/nutrient deficiency:


Do you have recurring pink eye? Night blindness? Skin issues, such as acne? Chronic respiratory infections?

You may have a vitamin A deficiency. Vitamin A supports eye health as well as skin, hair and nails. It is also vital for immune function, particularly in regards to lung and respiratory health. 

If you have a vitamin A deficiency, try increasing your intake of foods high in beta-carotene. These are colorful fruits and vegetables—orange and yellow (sweet potatoes, carrots, squash, apricots) as well as green leafy vegetables.


Thyroid issues? Hair loss? Weight gain? Brain fog? Swelling in the front of the neck?

You may have an iodine deficiency.

About 33% of the world population may have an iodine deficiency, which is more common with vegan and vegetarian diets, since iodine is found in seafood.

Iodine is responsible for metabolic function as well as the growth and repair of cells. It is a key mineral utilized by the thyroid gland to support optimal thyroid hormone production.

Foods high in iodine include seaweed and sea kelp, shellfish and eggs.


Vitamin C has many super powers, serving as an antioxidant and helping support optimal wound healing and immune function. It also has anti-inflammatory properties.

Bleeding gums? Tooth decay? Dry, brittle hair? Slow wound healing? Bruise easily? Frequent infections? Fatigue?

Our bodies aren’t able to synthesize vitamin C on our own—we must obtain vitamin C from diet and supplementation.

Smokers are at risk of vitamin C deficiency. If you take aspirin on a regular basis, you are also at risk for low vitamin C levels. 

Fruits and vegetables are loading with vitamin C. Kiwis, Brussels sprouts, oranges, tomatoes, grapefruit and berries are great choices.


Vitamin D supports your immune function and promotes bone growth. Also known as a the “sunshine vitamin,” plenty of sunshine helps support optimal vitamin D levels, but it may not be enough. Over 40% of Americans are vitamin D deficient.

If you’re dark skinned, don’t get much sunlight, are obese or have digestive issus or poor kidney function (prohibits the body’s ability to convert vitamin D to its active form)—you’re at increased risk of a vitamin D deficiency. Chronic illness, such as autoimmune diseases, also increase your deficiency chances.

Do your bones ache like the growing pains you had as a child? Gaining weight? Depressed? Fatigued? Have low bone mineral density? Muscle weakness? You may have low levels of vitamin D.

Testing vitamin D levels involves a simple blood test. Optimal levels are between 50-70.

Supplementation is likely required if your vitamin D levels are low. You can also help increase your levels by consuming foods high in vitamin D: mushrooms, eggs and fatty fish are high in vitamin D.



Through diet, you encounter vitamin K1 likely much more than K2. K1 is found in green leafy vegetables such as kale and spinach, asparagus and cruciferous vegetables.

K2, on the other hand, is more readily found in pasture raised livestock and fermented foods, which generally are not part of the Standard American Diet. Americans are not K1 deficient, but many are K2 deficient. K2 supplementation is usually necessary to meet the body’s needs.

While symptoms of low levels of vitamin K1 are easily detected (bruising, nose bleeds, poor wound healing, heavy menstrual periods, GI bleeds, blood in urine) a vitamin K2 deficiency is often silent. Vitamin K2 supports cardiovascular and bone health. Both plaque buildup in the arteries (atherosclerosis) and decreased bone density can be silent killers, taking years before any issues surface.

Vitamin K2 deficiency can occur due to insufficient dietary intake, but there are other ways you can become K2-deficient. Chronic conditions that interfere with your gut’s absorption rate, chemotherapy, dialysis patients and others are at risk of malnutrition. Certain pharmaceuticals also increase your chances of being K2-deficient. These medications include antibiotics, antacids, statins and anti-seizure drugs.

Antibiotics are a major culprit since your gut microbiome serve as assistants in producing K2. Long-term antibiotic use can affect your delicate microbiome in the small intestine, creating K2-deficiency.




B12 helps create red blood cells and the production of hemoglobin, transporting oxygen throughout your system. B12 also supports the nervous system and cognitive function.  

Symptoms of a B12 deficiency include balance issues, an inflamed and painful tongue, tingling in extremities, anemia, hair loss, fatigue and brain fog. Low levels of B12 may also affect mental health, leading to anxiety, depression, mood swings and even paranoia and hallucinations.

Because B12 is found mostly in animal-based foods, vegans are more susceptible to B12 deficiency. Common pharmaceuticals, such as PPIs (Nexium, Prilosec, Protonix, to name a few) as well as Metformin, the diabetic medication, reduce your body’s ability to absorb and utilize B12.  About 40% of the US population is B12-deficient.

Vegan sources of B12 include nutritional yeast and fortified coconut and almond milk—but food sources are usually not enough. Supplementation is necessary.

Be sure to choose methylcobalamin, the active and natural form of B12 rather than its synthetic step-sister, cyanocobalamin. There are also other forms of B12 that are bioavailable and help support optimal energy production, methylation and detoxification. 


B vitamin deficiencies may present as fatigue, adrenal issues, anemia, dry skin/dandruff, brain fog and mental health symptoms-depression, mood swings and diagnosed psychological disorders.

Birth control pills can cause a B vitamin deficiency, primarily B6, B12 and folate. These vitamins are crucial for proper methylation, DNA synthesis and neurological and cognitive function. Low levels of folate are linked to birth defects of the brain in spinal cord, increasing the risk by more than 70%.

Foods high in folate include legumes, leafy green vegetables and whole grains.

When supplementing with B vitamins, be sure they are in a bioavailable form—stay away from synthetic forms. Be sure you’re getting methyl folate, not folic acid. Methyl Folate (methyltetrahydrofolate) is the body’s most active form of folate. 



Responsible for so many functions in the body, a magnesium deficiency can cause a multitude of symptoms: nausea, lack of appetite, restless legs, weakness and fatigue, brain fog, muscle pain and cramping, eyelid twitching, migraines, heart palpitations, low vitamin D levels, erratic potassium and calcium levels, insomnia, anxiety and depression and more.

It is estimated that approximately 75% of Americans have a magnesium deficiency.

Certain medications may lead to a magnesium deficiency, such as PPIs (Nexium, Aciphex, Prilosec, to name a few). Long-term thiazide diuretic therapy can also lead to a magnesium deficiency.

Women require approximately 250-300 mg of magnesium a day; men need more, about 400 mg daily.

Magnesium is needed for every system—managing nerve and muscle function, hormone health, immune function and keeping your bones strong. Magnesium is also required for cardiovascular and cognitive health.

Foods high in magnesium include beans, dark chocolate, nuts and legumes as well as leafy, green vegetables, such as spinach.  Our soil today, however, is not as nutrient-dense as it once was, leaving our food nutrient-deficient. Daily supplementation is required to meet your body’s magnesium needs.

If you’re currently supplementing with vitamin D, your need for magnesium supplementation is even greater. Vitamin D requires magnesium for its own absorption, and will pull magnesium from your bones and tissue for its utility, leaving little for your body to retain.

It’s important to not take vitamin D and magnesium at the same time of day for this reason. Magnesium is best taken at night; vitamin D boosts energy levels and is recommended to be taken earlier in the day with a meal that contains healthy fat to aid in its absorption.