Vegan diets can have many health benefits, but they may not contain all the nutrients you need. To avoid a deficiency, a person should be sure to consume a variety of plant-based nutritious foods and consider taking supplements.

If a person does not plan his vegan diet very carefully, he may need to take extra vitamin B12 and iron. A person may also need extra vitamin D, iodine and omega-3 fatty acids.

Below, we look at why vegan diets may not contain all the necessary nutrients. We also describe the symptoms of specific deficiencies and which plant-based foods and supplements can help.

A well-planned vegan diet is rich in fruits and vegetables and generally low in highly refined foods.

However, any diet that does not contain whole food groups can contribute to the lack of certain nutrients. Animal products can be rich sources of certain nutrients that are more difficult to extract from a plant-based diet.

For example, animal products are the only natural sources of vitamin B12, which helps preserve blood cells and prevent anemia.

Researchers have also found that levels of zinc, protein, selenium and other nutrients are low on vegan diets.

However, consuming fortified foods and supplements can ensure that a person on a vegan diet is getting enough food.

Below, we describe the symptoms of common deficiencies and strategies for treating them.

Comprehensive diets usually contain enough B12 to meet the needs of most people. Since vegan diets do not include animal products, vitamin B12 deficiency can occur.

or transverse analysis of participants on a comprehensive, vegetarian or vegan diet found that about half of the 232 vegan participants were deficient in vitamin B12. Compared to other groups, the vegan group had the lowest overall levels.

According to National Institutes of Health (NIH), most teens and adults need 2.4 micrograms (mcg) of vitamin B12 per day. This increases to 2.6 mcg or 2.8 mcg for people who are pregnant or breastfeeding, respectively.

Vitamin B12 deficiency can cause symptoms that include:

  • fatigue
  • weakness
  • constipation
  • sudden weight loss
  • loss of appetite
  • tingling sensation in hands and feet
  • equilibrium problems
  • memory difficulties
  • bitterness of mouth and tongue
  • Turmoil

In addition, vitamin B12 deficiency can cause megaloblastic anemia. This includes the bone marrow that produces large, underdeveloped red blood cells, leading to low levels of red blood cells.

It can also occur from a lack of vitamin B9, also known as folate.

Some vegan foods are fortified with B12, but they may not provide enough. Taking a complex supplement B12 or B can help ensure an adequate intake of this important nutrient. Anyone worried about getting their B12 should talk to a healthcare provider.

Learn more about vitamin B12 here.

Omega-3 fatty acids CONTRIBUTING for heart and brain health.

Insufficient intake of omega-3 can also affect the skin, causing swollen redness, itching or dry scaly spots.

The three main types of omega-3 are alpha-linolenic acid (ALA), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA).

The body can convert ALA to DHA and EPA in very small amounts. For this reason, some people mainly focus on consuming ALA. However, the conversion rate is very low: Only 5-8% of ALA is converted to EPA and a maximum of 5% is converted to DHA.

As a result, it is essential to consume the sources of each omega-3. Plant-based foods that contain ALA include:

  • nuts, such as nuts
  • seeds, such as chia or flax seeds
  • vegetable oils, such as canola oil
  • fortified foods, such as cereals or juices

The very large concentration in ALA is also Dangerous because if a person consumes too much linoleic acid, a type of fat concentrated in foods including canola and soybean oil and nuts and seeds, this further inhibits the conversion of ALA to DHA and EPA.

Algae are a vegan spring of DHA and EPA. It currently is unclear how much DHA and EPA are needed for a healthy diet.

Learn more about omega-3 here.

The thyroid, a butterfly-shaped gland in the neck, converts iodine to the thyroid hormones triiodothyronine and tetraiodothyronine, known as T3 and T4, respectively. These hormones help regulate essential biological functions, for example metabolism.

The body does not produce iodine, so a person should get it from his diet. The recommended daily amount for adults is 150 mcgwith

Iodine deficiency can lead to hypothyroidism. Symptoms include:

  • inability to tolerate lower temperatures
  • fatigue
  • weight gain
  • a goiter

Learn more about hypothyroidism here.

Some vegetable sources of iodine They include:

  • iodized salt
  • soy milk
  • seaweed
  • bilberry
  • potato
  • dried plums

If a lab test detects an iodine deficiency, the person should take an iodine supplement.

Learn more about iodine here.

Iron is a mineral with several important functions throughout the body, including helping oxygen-carrying blood cells and supporting brain health.

Iron deficiencies may cause anemia, which limits the distribution of oxygen to cells around the body.

Other symptoms of iron deficiency include:

  • stomach problems
  • fatigue
  • weakness
  • difficulty concentrating or remembering
  • an increased susceptibility to infections

Iron heme is a form usual in meat, fish and eggs. The body absorbs it easily. Plant-based products contain joheme iron, which is more difficult to absorb.

E NIH report that adult males typically require about 8 mg of iron per day and adult females require about 18 mg. But since joheme iron is harder to absorb, people on vegan diets require about twice that amount.

Plant-based iron sources include:

  • nuts
  • some dried fruits, like raisins
  • legume
  • lentils
  • spinach
  • peas
  • iron-fortified cereals

Learn more about iron here.

Some people require an iron supplement, especially women of childbearing age.

Vitamin D helps absorb calcium for healthy bones and protect against chronic bone conditions, such as osteoporosis.

The body produces vitamin D from sun exposure. Few foods naturally contain vitamins, but manufacturers fortify many products with it, including cereals and milk.

There are two main types of vitamin D: D2 and D3. Vitamin D3 increases overall vitamin levels in the body higher and for longer than vitamin D2.

Animal products are the only natural source of vitamin D3, but vegan supplements are available. They use lichen as a source.

A person on a vegan diet can get D2 from supplements, mushrooms and fortified foods.

Vitamin D deficiency is very common and a person should check their levels with a blood test. Depending on the results, your doctor may recommend a supplement.

Learn more about vitamin D here.

Calcium is an important mineral for bone health and muscle function. A shortcoming can be increased risk of problems such as osteoporosis or bone fractures.

Symptoms of severe calcium deficiency include:

  • numbness or tingling sensation in the fingers
  • abnormal heart rhythms
  • convulsions

Vegan foods that contain calcium include:

  • broccoli
  • brussels sprouts
  • tie
  • green cabbage
  • mustard greens
  • chard
  • legume
  • peas
  • soy products

Fortified foods are also a source of calcium.

Learn more about calcium here.

Creatine is found in animal tissues and helps produce energy during exercise.

Vegan diets are common more shorter in creatine than other diets. While creatine is not an essential nutrient, it can improve athletic performance.

Taking a synthetics, and thus vegan, creatine supplementation can compensate for lower creatine reserves in muscle.

Learn more about creatine here.

For people on a vegan diet, doctors often recommend supplements, including B12. It’s a good idea to work with a knowledgeable healthcare provider, who can help develop a tailored plan to avoid nutritional deficiencies.

Having a more varied, targeted vegan diet can also account for low levels of certain nutrients. A health care provider can provide instructions regarding diet adjustment.

In general, it can also help in researching nutritional contents when planning meals.

A vegan diet may not contain all the necessary nutrients, such as vitamin B12. A person can address these deficiencies by adjusting their diet and taking vegan supplements.

It is also worth noting that general nutritional information may not be appropriate for people on a vegan diet. For example, a person may need twice the recommended amount of iron because iron from plant sources is more difficult for the body to absorb.