Giving your body the fuel it needs isn’t just a matter of finding the perfect balance of calories, carbs, fats, and protein. Your body requires more than two dozen vitamins and minerals to run thousands of processes, from building bones to firing nerve impulses to healing wounds. Being deficient in any of these micronutrients can have serious consequences for your health.
As Healthline explained, nutritional deficiencies can be caused by poor diet, medical conditions or medications that hinder absorption, or a combination of these two factors. Because the body can store some vitamins and minerals, certain deficiencies may only become apparent over time. Approximately 10% of Americans have some form of vitamin or mineral deficiency (via USA Today). According to Oregon State University, many others don’t consume the recommended amounts of key micronutrients, putting them at increased risk for a true deficiency in the future. An estimated 88.5% of Americans, for instance, don’t get enough vitamin E, while 52.2% don’t get enough magnesium.
If your daily diet isn’t as balanced as it could be or you think there’s a reason you may not be absorbing all the micronutrients you’re eating, keep an eye out for these warning signs that you may have a vitamin or mineral deficiency.
You may have a vitamin B12 deficiency if you get pins and needles in your hands and feet
Vitamin B12 is a water-soluble vitamin that plays several important roles in the body, including the creation of red blood cells and DNA synthesis. It’s also necessary for the proper development and functioning of the nervous system. In particular, vitamin B12 is required for the production of myelin, a protective sheath that covers the outside of nerves. This micronutrient occurs naturally only in animal foods such as meat, eggs, and dairy, although plant-based foods like breakfast cereals and nutritional yeast may be fortified with B12. Adult men and nonpregnant women need only 2.4 mcg of vitamin B12 daily. Most Americans consume enough vitamin B12, but strict vegans who don’t supplement are at risk for a B12 deficiency. Individuals may also become deficient as a result of difficulty absorbing vitamin B12 because of certain medical conditions or prolonged use of some types of medications (via the National Institutes of Health).
Because of vitamin B12’s involvement with the nervous system, particularly myelin creation, deficiency can lead to nerve damage. As Healthline explained, long-term B12 deficiency can cause myelin to form differently, which prevents nerves from working properly. This can produce a prickling pins and needles sensation in the hands and feet called paresthesia.
Strange-looking fingernails may be a sign you’re deficient in iron
Iron deficiency anemia is a common condition that results in too few healthy red blood cells. Iron deficiency can happen for a number of reasons. Some individuals may not consume enough iron-rich foods, while others may have difficulty properly absorbing the iron they eat. Individuals may lose excessive amounts of iron through blood loss (for example, heavy periods or an ulcer) or may become deficient during a time when their body requires more iron than usual (such as pregnancy). Whatever the cause, iron deficiency anemia can lead to a variety of symptoms, including extreme fatigue, shortness of breath, weakness, pale skin, and headaches (via the Mayo Clinic).
Iron deficiency can also leave its mark on your nails. According to a 2015 paper published in the Indian Dermatology Online Journal, koilonychia, also known as spoon nails, is a reverse curvature of the nails, causing them to become concave. Iron deficiency is the most common cause of koilonychia, but there are many other possible causes. Iron deficiency can also produce nails that are white, brittle, or have a central groove or ridge (via Podiatry Today).
Muscle cramps may mean you need more potassium
The National Institutes of Health (NIH) recommends that adult men get 3,400 mg of potassium daily, while nonpregnant women should aim for 2,600 mg. Potassium is found in a number of foods, and many fruits and vegetables are particularly high in this micronutrient. Potassium is considered a "nutrient of public health concern" because many Americans don’t get enough. The average U.S. adult man consumes only 3,016 mg a day, while the average woman consumes 2,320 mg. According to the NIH, "insufficient potassium intakes can increase blood pressure, kidney stone risk, bone turnover, urinary calcium excretion, and salt sensitivity." But most cases of low potassium levels are actually due to diarrhea, vomiting, or other medical conditions rather than not eating enough potassium.
Low potassium levels can lead to sudden, painful muscle cramps. As Healthline explained, potassium helps relay signals from the brain to the muscles, causing them to contract. When potassium leaves muscle cells, this causes the muscle contraction to end. But, "when blood potassium levels are low, your brain cannot relay these signals as effectively. This results in more prolonged contractions, such as muscle cramps."
Low magnesium could also be the cause of your twitchy muscles
When it comes to spazzy muscles, magnesium is another mineral that may be causing cramps and twitches. As McGill University explained, "deficiency in magnesium lowers the electrical threshold at which nerve cells become depolarized." In other words, nerve cells become hyper-excited, randomly firing off their electrical signals rather than working as part of a coordinated team. When this happens to nerves in our arms and legs it causes muscle spasms. But when magnesium-deprived nerves in the brain get hyper-excited, it can lead to seizures.
According to the National Institutes of Health, adults should get between 310 mg and 420 mg of magnesium daily, depending on age, sex, and pregnancy status. But approximately 48% of Americans don’t consume the recommended amount of magnesium. Among adults who don’t take supplements, the average intake was only 268 mg for men and 234 mg for women. Not consuming enough magnesium rarely leads to magnesium deficiency, since the kidneys control how much magnesium leaves the body. But certain medical conditions and medications, as well as alcohol abuse, can cause the body to lose too much magnesium, leading to deficiency.
Up your intake of vitamin A and if you have trouble seeing at night
If your eyes have trouble transitioning from a bright environment to a dark one, or driving after dark has become a challenge, you may be experiencing night blindness. While other vision issues, such as nearsightedness and cataracts, can make you more likely to be night blind, vitamin A deficiency can also be to blame (via Healthline). According to Healthline, vitamin A is needed to produce rhodopsin, a protein that allows the eyes to function in low light. Vitamin A is also important for maintaining a clear cornea (the outside covering of the eye) and may reduce your risk for cataracts.
The National Institutes of Health (NIH) recommends adult men get 900 mcg of vitamin A daily, while nonpregnant women should aim for 700 mcg. On average, however, adult men consume only 649 mcg, while women consume an average of 580 mcg. Although true vitamin A deficiency is rare in the United States, it’s common in other parts of the world. Vitamin A comes in two forms. Preformed vitamin A (retinol) is found in meat, eggs, and dairy, while provitamin A (carotenoids, including beta-carotene), is found in plant foods and converted by the body to retinol.
Corkscrew-shaped hairs are a telltale sign of vitamin C deficiency
Vitamin C is a water-soluble vitamin needed to make collagen, a protein that gives skin, connective tissue, and even blood vessels their structure. Adult men need 90 mg daily, while nonpregnant women should aim for 75 mg. Consuming less than 10 mg a day over an extended period of time can lead to scurvy — an acute and severe form of vitamin C deficiency. While uncommon in the United States today, scurvy can occur if you eat a diet devoid of fruits, vegetables, and vitamin C–enriched foods. Symptoms include fatigue, bleeding gums, tooth loss, pinpoint bruises in the skin, and depression (via the National Institutes of Health).
One unusual but telltale sign of scurvy is corkscrew or "swan neck" body hair. According to the National Institutes of Health, a lack of vitamin C prevents the proteins in hair from folding and binding to one another normally, creating a strange corkscrew or bent appearance. In a paper published by Dr. J. V. Hirschmann and Dr. Gregory J. Raugi, the development of corkscrew hairs appeared after 180-240 days without vitamin C.
If your wounds take forever to heal, you could be low in vitamins A and C
If you’re still nursing that papercut you got last week, you may not have enough vitamins A and C to properly close up even small wounds. According to a 2015 review published in the journal Wounds, many micronutrients, particularly vitamins A and C, play an important role in healing cuts and scrapes. Vitamin A stimulates growth of epithelial cells, which make up the epidermis or outermost layer of skin. Vitamin A also has an anti-inflammatory effect on wounds.
A 2013 paper published in the British Journal of Community Nursing outlined how vitamin C plays an important role in three of the four phases of wound healing (as described by Wound Source). During the inflammatory phase, vitamin C is required to clear away white blood cells after they’ve performed their function, preventing inflammation from getting out of control. In the proliferative phase, when new tissue is being created, vitamin C is needed for collagen production. Collagen is the protein that gives skin its structure and suppleness. During the maturation phase of healing, when collagen is realigned into an orderly network of fibers and the wound fully closes, insufficient vitamin C may lead to scarring.
Weak bones may be a sign you need more vitamin D
Although a calcium deficiency is probably the first thing that comes to mind when you think about weak, fracture-prone bones, a lack of vitamin D may also be to blame. According to the National Institutes of Health, vitamin D assists with calcium absorption in the gastrointestinal tract and helps maintain proper calcium levels in the blood. It’s also needed for proper bone growth during childhood and bone remodeling throughout adulthood. As the NIH explained, "Without sufficient vitamin D, bones can become thin, brittle, or misshapen. Vitamin D sufficiency prevents rickets in children and osteomalacia [softening of the bones] in adults." Exposure to sunlight is the best way to stock up on vitamin D, but fatty fish, mushrooms, and fortified products are also good options. Adults should get 20 mcg (800 IU) of vitamin D daily.
The bad news is that, while many other micronutrient deficiencies are rare in the United States, vitamin D deficiency appears to be extremely common. According to a 2011 study published in Nutrition Research, 41.6% of Americans have vitamin D levels that are too low. The percentage is even higher for some minority groups. Approximately 82% of Blacks and 69% of Hispanics are deficient.
Coordination problems could be a clue that you’re low on vitamin E
Vitamin E is a powerful fat-soluble antioxidant that protects the body from free radical damage. It also assists with communication between cells and plays a role in the immune system. Adult men and women need 15 mg of vitamin E daily. Good food sources of vitamin E include nuts, seeds, and vegetable oils like soybean and corn. Although most Americans may not meet the recommended dietary allowance (RDA) for vitamin E, true vitamin E deficiency is rare and is usually the result of problems with absorbing fat in the digestive tract, rather than not eating enough vitamin E–rich foods (via the National Institutes of Health).
One clue that vitamin E levels may be low is coordination problems and difficulty walking. This is because, according to a 2014 paper published in Neuroscience, vitamin E deficiency causes a breakdown in the structure and activity of Purkinje neurons. Purkinje neurons are a type of cell found in the cerebellar cortex of the brain. This is the outermost layer of the cerebellum, a part of the brain that controls voluntary movement, posture, and balance (via Verywell Mind).
Low copper levels could cause premature graying
The sad truth is that graying hair is just a fact of life as we age, but premature graying could be a sign of a nutritional deficiency. According to a 2013 study published in the Indian Journal of Dermatology, Venereology, and Leprology, graying occurs when melanocytes (pigment-containing cells in hair follicles) become less active. This happens naturally as we age, but can be spurred on by a number of health issues. Another 2012 study, published in Biological Trace Element Research, examined individuals who’d begun graying before age 20. The researchers noted that blood levels of copper were significantly lower in these individuals when compared to the control group, suggesting that copper deficiency may be behind some cases of premature graying.
The mineral copper assists with a variety of bodily processes, including extracting energy from food and absorbing and processing iron. Adult men and nonpregnant women need 900 mcg daily. Foods high in copper include shellfish, nuts and seeds, organ meats, and whole grains. Between 6% and 15% of adults don’t consume enough dietary copper, although true copper deficiency is uncommon (via the National Institutes of Health).
If you bruise easily, you may have a vitamin K deficiency
Vitamin K may not be as well-known as other vitamins, but it’s just as essential for good health. Your body uses vitamin K to produce proteins that oversee blood clotting. This process, also known as coagulation, prevents excessive bleeding both externally and internally. Easy bruising is an early sign of inadequate vitamin K levels. Although our bodies can produce one form of vitamin K, known as K2 (menaquinone), we get most of the vitamin K we need from food in the form of vitamin K1 (phylloquinone). Vitamin K deficiency is uncommon in the United States but can occur if you eat a diet extremely low in vitamin K, have difficulty absorbing fat (since vitamin K is a fat-soluble vitamin), or are taking antibiotics or certain types of blood thinners (via Healthline).
The National Institutes of Health recommends adult men consume 120 mcg of vitamin K daily, while nonpregnant women should aim for 90 mcg. The main sources of vitamin K in the American diet are broccoli, spinach, iceberg lettuce, canola oil, and soybean oil.
Choline deficiency could lead to anxiety and depression
Choline is a nutrient you’ve probably never heard of, but it’s essential for good health. According to the National Institutes of Health, choline is necessary for creating cell membranes as well as the neurotransmitter acetylcholine. Acetylcholine impacts memory, mood, and numerous other brain functions. Liver, eggs, meat, and soybeans are good sources of choline.
Because of choline’s role in creating acetylcholine, a deficiency could lead to depression, anxiety, and other psychological issues. According to the Brain & Behavior Research Foundation, depression may be caused by low levels of acetylcholine. This theory goes against the longstanding belief that depression is the result of low levels of a different brain chemical: serotonin. Antidepressants focus on raising serotonin levels, but increasing acetylcholine levels may, in fact, be what’s needed. As Professor of Neurobiology and Pharmacology at the Yale School of Medicine Marina R. Picciotto explained: "Serotonin may be treating the problem, but acetylcholine disruption may be a primary cause of depression. If we can treat the root cause, perhaps we can get a better response from the patient." A 2009 study published in The American Journal of Clinical Nutrition found that individuals who consumed the least amount of choline had a 33% greater chance of having anxiety.
The NIH recommends adult men get 550 mg of choline a day, while nonpregnant women need 425 mg. Most Americans, however, don’t consume the recommended amount. The average daily intake is 402 mg for men and 278 mg for women.
Cognitive difficulties could be a sign you have a calcium deficiency
While we usually associate calcium with bone health, this mineral plays many other important roles. According to the National Institutes of Health, calcium is needed to expand and contract blood vessels and produce hormones. It also assists with muscle function and nerve signaling. In fact, calcium is so important that its levels in the blood are very tightly controlled. The body uses bones as a sort of "bank" where it can store excess dietary calcium or extract calcium when the body needs it. The NIH recommends adults get between 1,000 and 1,200 mg of calcium daily, depending on sex and age. Because of how the body stores and regulates calcium, low calcium levels in the blood are usually the result of a medical condition (such as kidney failure) or medications (such as diuretics), rather than not eating enough calcium. Over time, however, not consuming enough calcium leads to brittle bones.
The Merck Manual noted that low calcium levels in the blood can cause confusion, memory problems, delirium, and hallucinations. One study, published in 2019 in the Journal of Alzheimer’s Disease, found that low levels of calcium in the blood were associated with a transition from mild cognitive impairment (MCI) to early Alzheimer’s Disease.
Problems with your sense of taste may mean you have a folate deficiency
COVID-19 isn’t the only thing that can rob you of your sense of taste; a deficiency of the B vitamin folate can also leave you unable to enjoy the flavor of your food. Folate, also known as vitamin B9, is a water-soluble vitamin found in a wide variety of foods, including dark leafy vegetables, fruits, nuts, legumes, eggs, dairy, meat, and grains. Folate plays an important role in DNA and RNA synthesis and cell division. This makes it particularly important during periods of rapid growth and development, such as during pregnancy. Adult men and nonpregnant women should get 400 mcg of folate daily, while pregnant women should consume 600 mcg. While most people get enough folate in their diet, individuals who over-consume alcohol, have certain genetic mutations, or have a medical condition that impacts micronutrient absorption (such as celiac disease) may end up with a folate deficiency (via the National Institutes of Health).
One of the more unusual symptoms of a folate deficiency is an impaired sense of taste. A lack of folate can cause the tongue to become red and smooth, and this loss of taste buds causes individuals to lose their sense of taste (via the Chicago Tribune). According to WebMD, other symptoms of folate deficiency include pins and needles or numbness in hands and feet, diarrhea, and muscle weakness.