Peeling nails, a twitching eyelid, flaky skin: These seemingly random symptoms are easy to brush off, but if they're persistent, they could be signs of a vitamin or nutrient deficiency.
"Stay in tune with your body, and if you notice something unusual, don't ignore it," says registered dietitian Jerlyn Jones, RDN, Atlanta-based owner of The Lifestyle Dietitian LLC and spokesperson for the American Academy of Dietetics and Nutrition.
"If a vitamin deficiency is causing the issue, the sooner you address it, the more easily it can be remedied through changes to your diet or a dietary supplement," she said.
What are the symptoms of a vitamin deficiency? As you'll see below, they can very much vary, depending on which vitamin the body is lacking.
Here, we look at eight signs that your system might be out of whack — plus, easy diet tweaks and tips to get back on track.
8 Surprising Symptoms of Vitamin Deficiencies
1. Your Joints Feel Stiff
The Possible Culprit: An achy bod can indicate that you're low on the sunshine vitamin. "Vitamin D helps you absorb calcium, which is one of the main building blocks of bones," Jones says. "If you don't get enough of it, either through food or sunlight, it can lead to bone density loss and soreness."
The Fix: So, how to get more of this nutrient? "You can eat foods rich in D, like salmon and egg yolks," Jones says, "but it's difficult to get adequate amounts through diet alone."
The easiest way to boost your D levels is by spending time in the sun. Indeed, vitamin D produced in the skin through sunlight may last at least twice as long in the body compared to ingesting the vitamin, according to a review in the April-June 2012 issue of the Journal of Pharmacology & Pharmacotherapeutics.
But sun exposure can also up your risk for skin cancer. Using sunscreen can limit the amount of D you get, but it's worth it to prevent this deadly disease, according to Yale Medicine.
If you're African-American, you're more susceptible to vitamin D deficiency because higher levels of melanin in your skin block absorption. The review mentioned above reports that it takes people with dark skin three to five times as long in the sun to make the equivalent amount of vitamin D as someone with light skin.
People who live in cold climates are also at greater risk, since they may not get adequate sun exposure. "In these cases, you will most likely need a supplement," Jones says.
But be cautious about DIY-ing your supplements — the Vitamin D Council warns that too much vitamin D can lead to toxicity, so it's best to get advice from your health care provider.
"Get your vitamin D status checked every four to six months," Jones says. "If it's too low, your doctor will probably write you a prescription."
2. Your Nails Are Peeling
The Possible Culprit: Brittle tips are typically due to an external factor — like picking at your polish, frequently using hand sanitizer or wearing acrylic nails.
But if both your toenails and fingernails are prone to breakage, you might be low on iron. "Iron deficiency results in limited oxygen to organs, muscles and tissue," Jones says. "One potential side effect of that reduced oxygen flow is peeling and brittle nails."
The Fix: Incorporate plenty of high-iron foods into your meals.
The no-brainer is meat, but if you follow a plant-based diet, leafy greens, baked potatoes with the skin on and broccoli are also great sources. For pescatarians: Try shrimp, scallops, clams and sardines.
"Consuming iron-rich foods along with vitamin C can boost absorption," Jones says. "For example, when you're sautéing spinach, throw in red peppers or tomatoes."
Another tip: Cook with cast iron. In a classic July 1986 study published in the Journal of the American Dietetic Association, researchers tested 20 foods cooked in either cast iron or glass-ceramic cookware, and found that cast-iron pots and pans significantly increased the iron content of 90 percent of the fare — particularly acidic foods with a high moisture content cooked for long periods of time, like applesauce and tomato sauce.
More recently, a small study of 27 preschoolers published December 2013 in the Journal of Indian Pediatrics found that cooking snacks in cast iron increased iron content by 16 percent; the children had 7.9 percent higher hemoglobin levels after four months of consumption.
A few weeks after making these changes, check your nails. If they're still weak, have your MD test your iron levels. "In cases of severe deficiency, your physician might give you an iron pill — drink it with orange juice for optimal results," Jones says.
3. One of Your Eyes Is Twitching
The Possible Culprit: The technical term is myopenia, and there are a variety of causes, from fatigue and stress to consuming too much caffeine and alcohol, according to the Mayo Clinic.
But your lids might also spasm if you're low on magnesium. And according to a March 2012 study in Nutrition Reviews, 48 percent of Americans are magnesium deficient.
Fortunately, it's relatively easy to up your intake.
The Fix: "Nuts and seeds — particularly pumpkin seeds — are high in magnesium," Jones says. "Sprinkle some on your oatmeal or salad, or mix half a cup into a smoothie."
Also, look for fortified breakfast cereal (it has added nutrients, including magnesium), and stick to either whole grains or white rice and bread that says "enriched" on the package.
4. You’ve Been Feeling 'Out of It' Lately
The Possible Culprit: Even though you're getting plenty of shuteye and aren't fighting a cold, you're dragging. Your muscles are weak and you have to force yourself out of bed in the morning; you have trouble staying on task and have been in a blah mood. What gives?
Feeling depleted might be evidence of a vitamin B12 shortage. B12 is key in red blood cell production, as Johns Hopkins Medicine explains. Red blood cells transport oxygen throughout your system, so if they aren't working efficiently, you'll feel worn out.
As for brain fog and the blues, a 2016 study published in the journal Current Medicinal Chemistry demonstrated that B vitamins are integral in neuronal function and that deficiencies can lead to depression.
The Fix: Jones suggests infusing your diet with B12 power foods like whole grains, liver and seafood such as salmon, tuna, clams and trout.
"B12 deficiency is relatively common in vegans and vegetarians, since it comes mostly from animal protein," she points out. "If you don't eat meat, ask your doctor to test your levels. You might have to take a multivitamin or supplement."
The average adult should get about 2.4 micrograms of B12 daily, according to the NIH. Three ounces of salmon, tuna or trout will provide more than enough, and a cup of milk or low-fat yogurt will get you halfway there.
5. You Bruise Easily
The Possible Culprit: Maybe you bump into your desk and find a gnarly black-and-blue on your thigh the next morning. Perhaps you get a nosebleed for no apparent reason. Or maybe your periods have been heavier than usual or your gums have been bleeding when you floss.
Insufficient vitamin K could be to blame. "Vitamin K is a coagulator that helps your blood clot properly," says Heidi Moretti, RD, a clinical dietitian and nutrition researcher. "If your levels are low, it can lead to excessive bleeding and bruising."
The Fix: You can find vitamin K in fermented foods like sauerkraut and aged cheese, as well as greens.
If eating more of those foods doesn't do the trick, "try a high-quality vitamin K2 supplement that's natural rather than synthetic," Moretti says. (Scan the label, and if you see any ingredients that begin with the prefix "dl," it's a factory-made.)
6. Your Skin Is Super Dry
The Possible Culprit: Scales and flakes are common side effects of arid fall and winter air, but they can also be a tipoff that you're low on fatty acids, reports the National Institutes of Health. Omega-3s play a key role in moisture retention, according to an August 2018 review in the journal Marine Drugs.
And the skin benefits don't stop there: According to the Linus Pauling Institute at Oregon State University, fatty acid consumption results in greater UV protection, fewer wrinkles, plumper skin and a more even complexion.
The Fix: Whip up a breakfast rich in omega-3s by stirring walnuts, chia seeds and flax meal into your cereal or oatmeal. Bite into a piece of avocado toast or crack open a can of sardines with lunch.
When you're out to dinner, order the salmon instead of chicken. "Get as many fatty acids as you can through food alone," says Melissa Halas-Liang, RD, spokesperson for the California Dietetic Association. "If you still think you might be lacking, make an appointment with a registered dietician to discuss a supplement."
7. You Lose Your Sense of Smell
The Possible Culprit: A sudden loss of your sense of smell or taste can be a symptom of a few conditions and, especially nowadays, is often tied to the coronavirus.
In some cases, however, loss of smell can be linked to vitamin deficiencies. As for which nutrient deficiency can contribute to a decreased sense of smell, findings often point to B12. Since taste and smell are so closely linked, a reduced sense of taste is sometimes associated with a deficiency of B12 as well.
Severe B12 deficiencies can damage the nerves throughout the body — including the ones required to make the olfactory system run.
As a result, individuals with severe vitamin B12 might lose or diminish their sense of smell, as an October 2016 study in the International Forum of Allergy & Rhinology found, adding that more research is needed to support these initial findings.
The Fix: If you're concerned that you have a vitamin B12 deficiency due to a loss of smell, you'll want to consult your doctor. Of course, getting enough B12 in your diet is always a good idea, too.
Consuming B12 in your diet can help to prevent vitamin deficiencies that can affect your sense of smell. Adults are advised to consume required approximately 2.4 micrograms of vitamin B-12 daily, according to the Linus Pauling Institute at Oregon State University.
In some cases, digestive issues might prevent the proper absorption of these vitamins. If you have a digestive disorder, consult with your doctor to discuss the risks of developing a B12 deficiency, and how best to prevent these deficiencies.
Vitamin B12 injections or nasal gels may help relieve a deficiency, but might not reverse the nerve damage that causes loss of smell.
Ask your doctor about having your B12 level checked if you are a strict vegetarian, have had weight-loss surgery or have a condition that interferes with the absorption of food.
8. Your Gums are Bleeding
The Potential Culprit: Bleeding gums are a sign of poor dental health, usually caused by inadequate dental cleanings and preventative care. These sensitive gums may be a sign of gingivitis or periodontitis, or it could be a vitamin deficiency that may cause bleeding gums.
While deficiencies in vitamin C and vitamin K are pretty rare, each has been linked with bleeding gums. A February 2021 review in Nutrition Reviews found that low vitamin C levels in the bloodstream were associated with an increased risk for gum bleeding with gentle probing. So it's possible that a vitamin C deficiency can cause bleeding gums.
People with vitamin K deficiencies are often more likely to experience bruising and bleeding, including in the gums, according to the U.S. National Library of Medicine.
The Fix: If, after a visit to the dentist, you learn that your oral health is in good shape despite bleeding gums, talk to your health care professional to check your levels of vitamins C and K. They may recommend eating more foods with these vitamins, a supplement routine or another treatment.
The researchers of the study in Nutrition Reviews noted that increasing vitamin C intake may help resolve the problem — so it's possible that increasing your citrus, broccoli, tomato and other foods with vitamin C intake may provide some relief.
The same may be the case for vitamin K deficiencies, though more research is needed. Foods including leafy greens like kale, spinach, turnip greens and collards, fish and cruciferous vegetables are good sources of the vitamin. Your doctor may also suggest a supplement.
While any of the above symptoms could indicate a vitamin or mineral deficiency, they could also be caused by something more serious. It's always best to make an appointment with your doctor to rule out any medical conditions.
Vitamin Deficiency Diseases
Certain vitamin deficiencies are disease related. Micronutrient deficiencies, including vitamin deficiencies, can affect anybody, although young children and pregnant women in certain developing nations are more commonly affected than others, according to the World Health Organization (WHO).
Deficiency diseases are diseases that are caused by the lack of certain essential nutrients, especially vitamins and minerals, in one's diet over a period of time.
Vitamin deficiency may be caused by an unhealthy diet, starvation or certain medical conditions that make absorbing nutrients difficult. Symptoms associated with vitamin deficiency diseases — and their likelihood — vary based on the disease and its severity.
For example, while vitamin A deficiency diseases are not common in the U.S., they are common in developing countries. Vitamin A deficiencies can can cause temporary and permanent eye damage. It may even lead to vision loss, and is the leading cause of preventable childhood blindness, according to the WHO.
The following list of vitamin deficiency diseases may give you a better understanding of certain terms and symptoms.
Rickets: A Vitamin D Deficiency
Rickets is a disease that causes soft, weak bones in children, per the U.S. National Library of Health. It often occurs when kids don't get enough vitamin D, which helps growing bones absorb the minerals calcium and phosphorous. It can also happen when calcium or phosphorus levels are too low.
Rickets is rare in the U.S. Treatments include replacing the calcium, phosphorus or vitamin D that are lacking in the diet.
Beriberi: A Vitamin B1 Deficiency
The symptoms you'll see on vitamin B deficiency list will vary depending on what type of vitamin B is being discussed. In the case of Beriberi, this condition is caused by a lack of thiamine, or vitamin B1, according to the U.S. National Library of Medicine.
Beriberi is an uncommon condition among people in the U.S., as most foods consumed within the nation are enriched with vitamins.
In the U.S. beriberi is most commonly seen among people who deal with alcohol abuse. Excessive alcohol consumption can result in poor nutrition, and it makes it harder for a person's body to absorb and store thiamine.
Pellagra: A Vitamin B3 Deficiency
Pellagra, also is known as vitamin B3 deficiency, occurs when a person fails to get sufficient amounts of niacin (B3) or tryptophan, per the U.S. National Library of Medicine. Tryptophan is one of 20 standard amino acids. Niacin is a water-soluble B vitamin that assists the digestive system, skin and nerves.
The most common cause of pellagra is insufficient amounts of niacin or tryptophan in the diet. This condition also occurs when a person's body fails to absorb these nutrients, or following certain gastrointestinal diseases or alcoholism.
Pellagra usually manifests in populations that consume large amounts of untreated corn. Common signs and symptoms associated with pellagra include delusions, diarrhea, inflamed mucus membranes, mental confusion and scaly sores on a person's skin.
Niacin supplements are often prescribed to treat pellagra.
- Yale Medicine: "Vitamin D Myths 'D'-bunked"
- Journal of Pharmocology & Pharmacotherapeutics: "Vitamin D: The 'sunshine' vitamin"
- Journal of the American Dietetic Association: "Iron content of food cooked in iron utensils."
- Journal of Indian Pediatrics: "Beneficial effect of iron pot cooking on iron status."
- Nutrition Reviews: "Suboptimal magnesium status in the United States: are the health consequences underestimated?"
- Mayo Clinic: "Eye twitching"
- Johns Hopkins Medicine: "Vitamin B12 Deficiency Anemia"
- Current Medicinal Chemistry: "The Effects of Vitamin B in Depression"
- National Institutes of Health: "Omega-3 Fatty Acids"
- Marine Drugs: "Cosmetic and Therapeutic Applications of Fish Oil’s Fatty Acids on the Skin"
- Linus Pauling Institute at Oregon State University: "Essential Fatty Acids and Skin Health"
- International Forum of Allergy & Rhinology: "Effect of vitamin B12 deficiency on olfactory function"
- Oregon State University: "Vitamin K"
- Oregon State University: "Vitamin C"
- Nutrition Reviews: "Bleeding tendency and ascorbic acid requirements: systematic review and meta-analysis of clinical trials"
- U.S. National Library of Medicine: "Vitamin K"
- U.S. National Library of Medicine: "Beriberi"
- U.S. National Library of Medicine: "Pellagra"
- WHO: "Micronutrients"
- U.S. National Library of Health: "Rickets"
- U.S. National Library of Health: "Vitamin A"
- WHO: "Vitamin A deficiency"