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
- Keratinized 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 intake of vitamin B1 for adults is between 1.1 and 1.3 mg/day.5
What vitamin B1 deficiency symptoms can occur?
Vitamin B1 deficiency leads to beriberi disease, 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
- Linseed (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
Similar to 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 about 1.3-1.4 mg, women about 1.0-1.1 mg, and pregnant women about 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 Signs and symptoms of vitamin B2 deficiency include skin disorders, hyperemia and edema of the mouth and throat, torn corners of the mouth, cheilosis (swollen, cracked lips), hair loss, sexual problems, sore throat, itchy and red eyes, and liver and nerve damage.[10,11]
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 utilization of our food and for the health of our skin, blood cells and 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 discoloration when skin has been exposed to sunlight. The skin also develops a rough, sunburn-like appearance14 In addition, pellagra can cause a noticeably red tongue and changes in the digestive tract leading to vomiting, constipation or diarrhea. Neurological complaints of pellagra include depression, apathy, headaches, fatigue, memory loss that can lead to aggressive behavior, 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?
As vitamin B5 is found in almost all foods, a deficiency is rare, except in people with severe malnutrition.17 When someone suffers from a vitamin B5 deficiency, it is usually accompanied by a deficiency of other nutrients, so it is difficult to identify the effects specific to a vitamin B5 deficiency. Vitamin B5 deficiency occurs almost exclusively in individuals who were taking 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 pregnant or breastfeeding20
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 more and more obvious as the deficiency progresses.
Vitamin B6 deficiency is associated with anemia, dermatitis with cheilosis (scaling of the lips and cracks at the corners of the mouth) and glossitis (swollen tongue), depression and confusion, and 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 insufficiency 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 is essential for the production of red blood cells, can lower homocysteine levels (blood levels of the amino acid homocysteine) and thus reduce 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?
Isolated vitamin B9 deficiency is uncommon and usually coexists with other nutrient deficiencies, as it is closely associated with poor nutrition, alcoholism and malabsorptive disorders. Megaloblastic anemia, characterized by large, abnormal blood cells, is the primary clinical sign of vitamin B9 deficiency.25 Symptoms include fatigue, feelings of weakness, difficulty concentrating, irritability, headaches, palpitations and shortness of breath.26Vitamin B9 deficiency can cause pain on 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
- Soybeans (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 supports the reduction of 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 characterized by fatigue, general weakness, anemia, 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 anemia, which is why early diagnosis and intervention is important to avoid incurable damage.32