Vitaminmangel

Recognising and preventing vitamin deficiency symptoms

If you're looking for ways to improve your quality of life, you've come to the right place! Vitamins are micronutrients that are essential for your well-being. We explain which vitamins are available and where you can get them reliably.

By definition, vitamins are foods that your body needs to perform various vital functions. All vitamins are essential for your body and, as the name suggests, essential for your everyday vitality. Only vitamin D and vitamin B3 can be produced by your body. Most vitamins must be taken through your diet. In this article, we explain what role the vitamins fulfil in your body, how much you should take and how potential deficiency symptoms can manifest themselves.

Frequent vitamin deficiency symptoms and their potential cause

Symptom: Lack of

Concentration deficiency: Vitamin D

Fatigue: vitamin D, vitamin B12

Rash on areas that are often exposed to the sun: Vitamin B3

Slight bruising/bruising: Vitamin K, Vitamin C

Dementia: Vitamin B1, vitamin B3, vitamin B12

Sensitive bones: Vitamin D

Painful severely red or swollen lips: Vitamin B2, vitamin B3, vitamin B6

Inflammation of the tongue: Vitamin B2, vitamin C

Abnormal tingling or numbness: vitamin B1

Joint swelling or pain: Vitamin C

Cognitive deficits: Vitamin B1, Vitamin B3, vitamin B6, vitamin B12

Impaired night vision: Vitamin A

Clouding of the cornea/blurred vision: vitamin A

Numbness: vitamin B1, vitamin B12

Frequent bleeding gums or tooth loss: vitamin C

Vitamin A: for eyes and skin

Vitamin A produces the pigments in our eye retina. In addition to the eyes, vitamin A is essential for the health of the skin. The recommended daily intake for adults is approx. 1.0 mg for men and 0.8 mg per day for women.1

What vitamin deficiency symptoms can occur with vitamin A?

Vitamin A deficiency is the leading cause of preventable blindness in children. A lack of vitamin A can cause the following symptoms:

  • Xerophthalmia: dry, thickened conjunctiva and cornea
  • Night blindness
  • Cornified growths (metaplasia) on the conjunctiva that lead to blurred vision2

Natural sources of vitamin A
  • Sweet potatoes (961 μg/ 100 g)
  • Carrots (852 μg/ 100 g)
  • Tuna (757 μg/ 100 g)
  • Pumpkin (558 μg/ 100 g)
  • Spinach (524 μg/ 100 g)
  • Honeydew melon (169 μg/ 100 g)

Vitamin B1: Essential for carbohydrate metabolism

Vitamin B1 is particularly important for carbohydrate metabolism.3 It helps to break down and release energy from food. It is therefore indirectly extremely important for the general health of the skin, hair, muscles, brain and nerves.4 The need for vitamin B1 decreases slightly with age. The recommended daily dose of vitamin B1 for adults is between 1.1 and 1.3 mg/day.5

What vitamin B1 deficiency symptoms can occur?

As a result of vitamin B1 deficiency, beriberi disease develops, which is particularly common among alcoholics. It leads to peripheral neuropathy. People with this disease have impaired sensory, motor and reflex functions.6

Natural sources of vitamin B1
  • Both fresh and dried fruits
  • Flaxseed (1.6mg/100g)
  • Salmon (0.3mg/100g)
  • Peas (0.3mg/100g)
  • Tofu (0.2mg/100g)
  • Brown rice (0.2mg/100g)7

Vitamin B2: for skin, brain, hair, blood and nerves

Like B1, B2 is extremely important for the health of the skin, brain, hair, blood and nerves, as it also plays an important role in our body's energy metabolism. Men need around 1.3-1.4 mg, women around 1.0-1.1 mg and pregnant women around 1.3-1.4 mg of vitamin B2 per day.8

What vitamin B2 deficiency symptoms can occur?

Vitamin B2 deficiency is extremely rare, but the consequences can be varied and serious. In addition to insufficient intake, endocrine abnormalities (such as thyroid hormone deficiency) and various diseases can be caused by vitamin B2 deficiency.9 The signs and symptoms of vitamin B2 deficiency include skin diseases, hyperaemia and oedema of the mouth and throat, cracked corners of the mouth, cheilosis (swollen, chapped lips), hair loss, sexual problems, sore throat, itchy and red eyes as well as liver and nerve damage.

Natural sources of vitamin B2
  • Almonds (1.1mg/100g)
  • Salmon (0.5mg/100g)
  • Mushrooms (0.5mg/100g)
  • Spinach (0.5mg/100g)
  • Eggs (0.5mg/100g)

Vitamin B3: for your immune system

Vitamin B3 is very important for the energy utilisation of our food and for the health of the skin, blood cells and the brain. It plays a central role in the function of the nerves and liver.12 In adults, the daily requirement of vitamin B3 decreases slightly with age. Men need approx. 14-16 mg per day, women approx. 11-13 mg per day and pregnant/breastfeeding women approx. 14-16 mg per day.13

What vitamin deficiency symptoms can occur?

Severe vitamin B3 deficiency leads to a condition called pellagra. Pellagra causes a skin rash or brown discolouration when skin has been exposed to sunlight. The skin also develops a rough, sunburn-like appearance.14 In addition, pellagra can cause a noticeably red tongue and changes in the digestive tract leading to vomiting, constipation or diarrhoea. Neurological symptoms of pellagra include depression, apathy, headaches, fatigue, memory loss, which can lead to aggressive behaviour, and visual hallucinations.15

Natural sources of vitamin B3
  • Tuna (22.1mg/100g)
  • Peanuts (14.4mg/100g)
  • Chicken breast (9.5mg/100g)
  • Portobello mushrooms (6.3mg/100g)
  • Brown rice (2.6mg/100g)

Vitamin B5: for a stable hormone balance

Vitamin B5 is not only important for energy metabolism, like other B vitamins, but also helps in the production of neurotransmitters, steroid hormones, fatty acids and haemoglobin. Adolescents and adult men and women require 6 mg of vitamin B5 per day from the age of 14.16

What vitamin B5 deficiency symptoms can occur?

Since vitamin B5 is found in almost all foods, a deficiency is rare, except in people with severe malnutrition.17 When someone suffers from vitamin B5 deficiency, it is usually accompanied by deficiencies in other nutrients, making it difficult to identify the effects specific to vitamin B5 deficiency. Vitamin B5 deficiency occurs almost exclusively in individuals who have taken vitamin B5 metabolic antagonists18

Natural sources of vitamin B5
  • Sunflower seeds (7 mg/ 100g)
  • Shiitake mushrooms (3.6 mg/ 100g)
  • Salmon (1.9 mg/ 100g)
  • Avocados (1.4 mg/ 100g)
  • Sweet potatoes (0.5 mg/ 100g)

Vitamin B6: for the production of red blood cells

Vitamin B6 helps to regulate homocysteine levels (blood levels of the amino acid homocysteine) and can reduce the risk of heart disease. It supports the conversion of tryptophan into niacin and serotonin, a neurotransmitter that plays a central role in sleep, appetite and mood. Vitamin B6 helps in the formation of red blood cells and influences cognitive abilities and immune function.19 Adult men have a daily requirement of 1.6 mg of vitamin B6 per day. Women 1.4 mg per day or 1.5-1.8 mg per day if they are pregnant or breastfeeding.20

What vitamin B6 deficiency symptoms can occur?

An isolated deficiency of vitamin B6 is extremely rare and is usually associated with low concentrations of other B-complex vitamins, such as vitamin B12. A vitamin B6 deficiency causes biochemical changes that become increasingly obvious as the deficiency progresses.

Vitamin B6 deficiency is associated with anaemia, dermatitis with cheilosis (scaling of the lips and cracks at the corners of the mouth) and glossitis (swollen tongue), depression and confusion, as well as a weakened immune system. People with a mild deficiency may have no deficiency signs or symptoms for months or even years. In infants, vitamin B6 deficiency leads to irritability, abnormal hearing loss and convulsive seizures.21 End-stage renal disease, chronic renal failure and other kidney diseases can also cause vitamin B6 deficiency.22

Natural sources of vitamin B6
  • Salmon (0.9 mg/ 100g)
  • Tofu (0.5 mg/ 100g)
  • Bananas (0.4 mg/ 100g)
  • Potatoes (0.3 mg/ 100g)
  • Sweet potatoes (0.2 mg/ 100g)

Vitamin B9: prevents heart disease

Vitamin B9, also known as folic acid, is essential for the production of red blood cells and can lower homocysteine levels (blood levels of the amino acid homocysteine), thereby reducing the risk of heart disease. It helps prevent birth defects of the brain and spine when taken early in pregnancy. Adult men and women need about 300 µg of vitamin B9 per day. Breastfeeding women approx. 450 µg and pregnant women approx. 550 µg per day.23

What vitamin B9 deficiency symptoms can occur?

An isolated deficiency of vitamin B9 is uncommon and usually coexists with other nutrient deficiencies, as it is closely associated with poor nutrition, alcoholism and malabsorptive disorders. Megaloblastic anaemia, characterised by large, abnormal blood cells, is the primary clinical sign of vitamin B9 deficiency.25 The symptoms of folic acid deficiency include tiredness, feelings of weakness, difficulty concentrating, irritability, headaches, palpitations and shortness of breath.[<[sup>26A vitamin B9 deficiency can cause pain in the tongue and oral mucosa, changes in skin, hair or fingernail pigmentation, and increased homocysteine concentrations in the blood.27

Natural sources of vitamin B9
  • Soy beans (311 μg/ 100 g)
  • Lentils (181 μg/ 100 g)
  • Asparagus (149 μg/ 100 g)
  • Spinach (146 μg/ 100 g)
  • Broccoli (108 μg/ 100 g)

Vitamin B12: for DNA synthesis

Vitamin B12 helps to lower homocysteine levels (blood levels of the amino acid homocysteine) and can therefore reduce the risk of heart disease, just like vitamin B9. It contributes to the formation of red blood cells and DNA. Vitamin B12 helps with the formation of new cells, the breakdown of some fatty acids and promotes the growth of nerve cells.28 The daily requirement for vitamin B12 for adult men and women is approx. 4.0 µg per day. Pregnant women need approx. 4.5 µg and breastfeeding women approx. 5.5 µg.29

What happens with vitamin B12 deficiency

Vitamin B12 deficiency is characterised by fatigue, general weakness, anaemia, loss of appetite and weight loss.30 Neurological problems, such as numbness and tingling in the hands and feet, can occur31 Other symptoms of vitamin B12 deficiency include depression, confusion, balance problems, dementia, poor memory and pain in the mouth or on the tongue. The neurological symptoms of vitamin B12 deficiency can also occur without anaemia, which is why early diagnosis and intervention is important to avoid incurable damage.32

Natural sources of vitamin B12
  • Mussels (98.9 μg/ 100 g)
  • Tuna (10.9 μg/ 100 g)
  • Beef (7.5 μg/ 100 g)
  • Eggs (1.1 μg/ 100 g)
  • Milk (0.5 μg/ 100 g)

Vitamin C: is required for the production of collagen

Our body needs vitamin C to form collagen33, a connective tissue that is needed to heal wounds and supports the blood vessel walls. Vitamin C helps in the formation of neurotransmitters (noradrenaline and serotonin). It is also an antioxidant and neutralises unstable molecules that can damage cells and thus cause cancer.34 Adult men need around 110 mg, women 95 mg, pregnant women 105 mg and breastfeeding women 125 mg of vitamin C per day.35

What vitamin C deficiency symptoms can occur?

An acute vitamin C deficiency develops relatively quickly compared to other nutrient deficiencies. Vitamin C deficiency leads to scurvy36 The time it takes for scurvy to develop varies greatly, but the first signs can appear within a month.37

Initial symptoms can include tiredness, malaise and inflammation of the gums.38 As vitamin C deficiency progresses, collagen synthesis is disrupted and connective tissue is weakened, leading to petechiae, joint pain, poor wound healing or hyperkeratosis.39 Other signs of scurvy include depression as well as swollen, bleeding gums and loosening or loss of teeth due to tissue fragility and capillary weakness (due to the lack of collagen).40

Natural sources of vitamin C
  • Guava (228 mg/ 100 g)
  • Peppers (128 mg/ 100 g)
  • Kiwi (93 mg/ 100 g)
  • Strawberries (59 mg/ 100 g)
  • Orange (53 mg/ 100 g)

Vitamin D: strengthens the bones

Vitamin D helps to stabilise normal calcium and phosphorus levels in the blood, which strengthens bones. It also supports the formation of teeth and bones. Vitamin D can be synthesised naturally in the body if you are regularly exposed to the sun. If an adult gets hardly any sunlight in daily life, they should take around 20 µg per day in the form of a dietary supplement.41

These are the typical vitamin D deficiency symptoms

Rickets and osteomalacia are the classic vitamin D deficiency diseases. In children, vitamin D deficiency causes rickets, a disease characterised by a lack of mineralisation of bone tissue, leading to soft bones and skeletal deformities.[<[sup>42

In adults, vitamin D deficiency can lead to osteomalacia, which results in bone weakness. Symptoms of bone pain and muscle weakness may indicate inadequate vitamin D levels, but such symptoms can be subtle and go undetected in the early stages.43

Natural sources of vitamin D
  • Salmon (16.7 μg/ 100 g)
  • Mushrooms (that have been in the sun) (31.9 μg/ 100 g)

Vitamin E: neutralises unstable molecules

Vitamin E is an antioxidant that neutralises unstable molecules that can damage cells. It also protects vitamin A and fatty acids from damage. The need for vitamin E decreases with age. Adult men need approx. 12-15 mg per day and women approx. 11-12 mg per day.44

What vitamin E deficiency symptoms can occur?

Since the digestive tract needs fat to absorb vitamin E, people with fat absorption disorders are more likely to be deficient than those without such disorders.45 The symptoms of vitamin E deficiency include retinopathy, peripheral neuropathy, skeletal muscle myopathy, ataxia, and impairment of the immune system.46

Natural sources of vitamin E
  • Sunflower seeds (26.1 mg/ 100 g)
  • Almonds (25.6 mg/ 100 g)
  • Avocados (2.1 mg/ 100 g)
  • Spinach (2.1 mg/ 100 g)
  • Butternut squash (1.3 mg/ 100 g)

Vitamin K: essential for blood clotting

Vitamin K activates various proteins and calcium and is therefore particularly essential for blood clotting. The recommended daily dose of vitamin K for adult men is approx. 70-80 µg per day. An adult woman needs approx. 60-65 µg per day and approx. 60 µg per day if she is breastfeeding or pregnant.47

What vitamin deficiency symptoms can occur?

Hemorrhage is the classic sign of vitamin K deficiency, although these effects only occur in severe cases. As vitamin K is required for the carboxylation of osteocalcin in bone, vitamin K deficiency can reduce bone mineralisation and thus contribute to osteoporosis or a general reduction in bone density.48

Natural sources of vitamin K
  • Cabbage (419 μg/ 100 g)
  • Broccoli (141 μg/ 100 g)
  • Cabbage sprouts (140 μg/ 100 g)
  • Asparagus (51 μg/ 100 g)
  • Kiwi (40 μg/ 100 g)

Frequently asked questions about vitamins
Which vitamins are lacking in fatigue?

Deficiencies in vitamins B12, C and D can cause fatigue. However, as vitamin C deficiency is very rare in developed countries, you should keep an eye on your vitamin B12 and vitamin D levels. Vitamin B12 deficiency inhibits the production of red blood cells, which impair oxygen transport in the body49 This makes you feel tired or sluggish. Even a small deficiency of vitamin D can lead to tiredness and a general feeling of poor well-being.50
Which vitamins am I missing?

Our symptom table may help you to find out which vitamin deficiency you could be suffering from. Nevertheless, you should always discuss any suspicious symptoms or complaints with your doctor. They can check for a suspected deficiency using a blood test.
What vitamin deficiency in dry skin?

One of the best-known symptoms of vitamin D deficiency is dry skin. Vitamin D is particularly important for the health of your skin as it stimulates receptors that are responsible for the formation of the skin barrier, which is essential for protecting the skin.51
What are the symptoms of vitamin B deficiency?

There are many different B vitamins that fulfil a wide variety of functions in the body. It is important not to pigeonhole them all, as deficiencies of these different vitamin B variations can lead to different symptoms. Our symptom table should give you a good overview.
What do vitamins do in the body?

Vitamins enable a wide variety of functions in our body. Without vitamins, our body would not be able to fulfil vital tasks such as converting food into energy, building and maintaining bones, teeth, muscles, skin, blood and hair, as well as maintaining the functionality of our brain, eyes, nervous and immune systems.
Which vitamins for listlessness?

A deficiency of many different vitamins and minerals can lead both directly and indirectly to a lack of motivation. The lack of motivation is often accompanied by tiredness and concentration problems. A lack of B vitamins, vitamin D or the minerals iron and magnesium can cause listlessness particularly quickly.52
Which vitamins together take table?

To provide your body with the best conditions for efficient absorption of nutrients into the blood, consider combining the following nutrients. Some nutrients complement or interfere with each other's function in your body - so depending on what and when you eat, you can either enhance or miss out on the benefits of these healthy foods (and supplements).

Calcium and vitamin D
Most of the calcium we absorb in our bodies is stored in our bones and vitamin D helps to absorb, transport and deposit this calcium in our bones.53

Vitamin D and healthy fatty acids
Vitamin D is a fat-soluble vitamin. This means that it must be mixed with fat in order to be absorbed by the body. It is therefore advisable to combine vitamin D-rich foods with a high-quality fat such as olive oil, linseed, avocado, fish, chia seeds or nuts.54

Iron and vitamin C (especially for vegetarians)
Iron can be obtained from plant and animal foods. Although plant foods contain a lot of iron, it can often only be absorbed to a limited extent due to other substances - such as oxalic acid in spinach. Vitamin C compensates for this absorption-inhibiting effect as it promotes iron absorption.55
How do you realise that you have a vitamin deficiency?

Symptoms of a vitamin deficiency can be very varied and depend on the vitamin in question. Common signs include tiredness, poor concentration, susceptibility to infections, dry skin, brittle nails and hair, muscle weakness or mood swings. As these symptoms can also occur with other illnesses, it is advisable to seek medical clarification with a blood test if a vitamin deficiency is suspected.
Which vitamin deficiency is the most common?

According to the national consumption study, an insufficient supply of vitamin D is most widespread in Germany, especially in the winter months. As vitamin D is mainly produced by sun exposure of the skin, many people have a deficiency if they spend too little time outdoors. Folic acid, iodine and iron are also among the critical nutrients that are often deficient.

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Sources
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