8 Common Nutrient Deficiencies on a Low-Carb Diet

People who go on restrictive diets may not get all of the nutrients that they need. Those who choose low-carb diets—either for weight loss or health management—may not get enough of certain nutrients including thiamin, folate, vitamin C, magnesium, iron, vitamin D, vitamin E, vitamin B7 (biotin), fiber, and calcium. These are the most common nutrients that are likely to be deficient, but depending on the particular diet, there may be more.

To make sure that your body functions well on a low-carb diet, consider the sources of each of these micronutrients. Then try to include these foods in your meals and snacks throughout the day so that you get the recommended daily intake of each essential nutrient.



Verywell / Alexandra Shytsman

Thiamin (sometimes spelled "thiamine") is important for energy production and brain and nervous system function. Thiamin is also called vitamin B1.

Thiamin works with other B vitamins, so a depletion of one can cause others to function less effectively in the body. This vitamin is also prone to destruction in food processing, storage, and cooking. For this reason, some flour and cereal products are enriched with thiamin.

Low-Carb Sources of Thiamin

Adult women should consume 1.1 milligrams (mg) and men should consume 1.2 mg of thiamin each day.

  • Pork loin: 3 ounces uncooked = 0.5 mg thiamin
  • Macadamia nuts: 1 ounce = 0.3 mg thiamin
  • Pecans: 1 ounce = 0.2 mg thiamin
  • Peanuts: 1 ounce = about 0.2 mg thiamin
  • Flaxseed: 1 tablespoon = 0.2 mg thiamin
  • Asparagus: 1 cup = 0.2 mg thiamin
  • Chicken livers: 3 ounces = 0.1 mg thiamin

Many non-starchy vegetables provide .06 mg to .09 mg thiamin per cup. Nutritional yeast or brewer's yeast can also provide thiamin, but look for a sugar-free variety. Some brands are fortified with B vitamins so that a teaspoon of nutritional yeast will provide the recommended daily intake. For unfortified yeast, two tablespoons provide about 0.6 mg of thiamin. Brewer's yeast provides slightly less.


Folate is possibly best known for preventing neural tube defects, a type of birth defect. Folate is necessary for many chemical reactions in the body and plays a role in cell formation, especially red cell formation.

Folate is also known as vitamin B9, and it's commonly found in whole foods. Folic acid is the synthetic form found in supplements and fortified foods. Folic acid is more bioavailable—meaning that the body is better able to use it.

Low-Carb Sources of Folate

Adult women and men should consume 400 micrograms (mcg) of folate per day. (Pregnant women need more.)

Salmon, crab, lamb, and most green vegetables are also good sources of folate.

Vitamin C

Probably the most well-known vitamin, vitamin C performs many functions in the body. This vitamin is essential for brain neurotransmitters to function properly and it protects our cells from damage. Vitamin C is also necessary for building connective tissue and promotes resistance to infection.

Vitamin C is easily degraded during storage and cooking. To enhance the vitamin C content of your food, keep produce cool and try not to overcook it.

Low-Carb Sources of Vitamin C

Adult women should consume 75 mg and men should consume 90 mg of vitamin C each day.

  • Red bell pepper: 0.5 cup raw = 95 mg vitamin C
  • Strawberries: 1 cup sliced = 89 mg vitamin C
  • Broccoli: 1 cup chopped, raw = 81 mg vitamin C
  • Green bell pepper: 0.5 cup raw = 60 mg vitamin C
  • Brussels sprouts: 0.5 cup raw = 48 mg vitamin C
  • Cauliflower: 1 cup = 46 mg vitamin C
  • Grapefruit: 0.5 fruit = 38 mg vitamin C
  • Cabbage: 1 cup chopped, raw = 33 mg vitamin C

Other good sources of vitamin C include kale and other leafy greens, raspberries, green beans, and cantaloupe. Almost all fruits and vegetables have some vitamin C.


Magnesium plays a wide range of roles in the body, supporting protein synthesis, bone development and maintenance, DNA synthesis, and cell function. Many of us don't get enough magnesium. In fact, according to some estimates, 30% to 50% of Americans don't reach the recommended daily intake.

Unfortunately, people on low-carb diets may fare even worse. In one study, 70% of people on the Atkins diet were not getting sufficient magnesium. People on low-carb diets may need magnesium more than others since it is important in glucose metabolism and blood sugar control.

Low-Carb Sources of Magnesium

Adult women should consume 320 mg and men should consume 400 mg of magnesium each day.

  • Soybeans: 1 cup raw = 521 mg magnesium
  • Pumpkin seeds: 1 cup roasted = 168 mg magnesium
  • Almonds: 1 ounce = 77 mg magnesium
  • Peanuts: 1 ounce = 48 mg magnesium
  • Flaxseed: 1 tablespoon whole seeds = 40 mg magnesium
  • Spinach: 1 cup raw = 24 mg magnesium

Other good sources of magnesium include legumes, fish, green vegetables, and yogurt.


Iron is extremely important to our health. Without it, our cells cannot get oxygen. Iron is responsible for hemoglobin formation, improves the quality of our blood, and increases resistance to disease and stress. And yet, especially for women of childbearing age, iron deficiency is not uncommon. People on low-carb diets tend to consume less of it.

Pair iron rich foods with foods that contain vitamin C for better absorption. For example, pair red bell pepper with chicken, or spinach with beans,

Low-Carb Sources of Iron

Adult women of childbearing age should consume 18 mg of iron each day. Men and women over childbearing age should consume 8 mg of iron each day.

  • Soybeans: 0.5 cup raw = 15 mg iron
  • Chicken liver: 4 ounces raw = 10 mg iron
  • Beef liver: 4 ounces raw = 5.5 mg iron
  • Black beans: 1 cup = 4.6 mg iron
  • Oysters: 3 ounces raw = 4.3 mg iron
  • Roast beef: 4 ounces = 4 mg iron
  • Mussels: 3 ounces raw = 3.4 mg iron
  • Asparagus: 1 cup = just under 3 mg iron
  • Tuna: 1 can (107g) = 1.8 mg iron
  • Spinach: 1 cup raw = about 1 mg iron

Vitamin D, Vitamin E, and Calcium

Deficiencies in these nutrients aren't specific to low-carb diets. Many people on a typical American diet don't get enough vitamin D, vitamin E, or calcium.

Vitamin D

Vitamin D is necessary for the maintenance and balance of calcium and phosphorus in the body. This micronutrient also plays a role in other systemic functions in the body.

Getting enough vitamin D can be difficult through food sources alone. Exposure to the sun provides many of us with the amount that we need. However, vitamin D deficiency is becoming more common. Some believe that it may be due to the fact that people are spending less time outside—especially in winter and in areas far from the equator. In addition, people are also more responsible about wearing sunscreen. 

The recommended intake of vitamin D is 600 IU daily for adult men and women. Low-carb sources of vitamin D include salmon, tuna, eggs, yogurt, and liver. Certain foods are also fortified with vitamin D, such as milk alternatives, like almond milk. In addition, mushrooms and sardines are also good sources of vitamin D.

Vitamin E

Vitamin E is a fat-soluble vitamin that functions as an antioxidant. There are eight different forms of the nutrient, which is one of the reasons it's best to get vitamin E from foods. Vitamin E supplements usually only contain one or two forms.

The recommended intake of vitamin E is 15 mg daily for adult men and women. Low-carb sources of vitamin E include most nuts and seeds (especially sunflower seeds), greens, avocado, peppers, and shrimp.


Calcium plays many roles in the body, but it's best known for the development of bone mass and maintenance of bone strength. It's also vital to the functioning of our muscles and nerves and maintaining the correct acid/base balance.

The recommended intake of calcium is 1,000 mg daily for adult men and women. However, women over the age of 51 should consume 1,200 mg per day. Low-carb sources of calcium include dairy products, sardines, canned salmon, tofu, and dark green vegetables.

Common Questions

Many people following a low-carb diet may have questions about vitamin and mineral intake, as well as getting enough micronutrients.

Is It Better to Get Nutrients From Supplements or Food?

Supplements provide a tempting alternative when you consider the foods you need to eat to get all of these important vitamins and minerals. But they are not always the smartest choice.

Researchers are discovering that there are many nutrients in foods that we either didn't know about before or that need to work together in the food that we eat. For example, scientists have identified tens of thousands of phytonutrients in the plant foods we eat. We are just beginning to understand the complexities of how they interact.

Additionally, supplements may not always provide the amount of a nutrient that you need—even if it says so on the label. Food sources provide both micro and macronutrients (protein, carbs, and fats).

Does Not Meeting the RDI Mean You Have a Deficiency?

There are differences between having a diagnosed condition from a nutrient deficiency (such as rickets or anemia), having a low blood level of a nutrient, and not getting the recommended daily intake (RDI) of a given nutrient in your diet.

Your healthcare provider may give you blood tests and perform other types of assessments to make sure your body is getting the nutrients it needs to perform properly. If you have other questions about a potential vitamin deficiency on a low-carb diet, speak to your healthcare provider or a registered dietitian.

11 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Additional Reading

By Laura Dolson
Laura Dolson is a health and food writer who develops low-carb and gluten-free recipes for home cooks.