The bioavailability of vitamins in the human body

How to improve vitamin absorption

Having a balanced diet that includes all vitamin types is vital for good health and a long life. However, each vitamin is absorbed in a specific way, so if we want to avoid vitamin deficiencies we need to learn the best strategies for improving how we consume them.

Below we explain some of these strategies and how they can help us to improve our vitamin absorption.

How are vitamins best absorbed?

The body’s capacity to absorb vitamins depends largely on whether they are water- or fat-soluble. Water-soluble vitamins include group B vitamins and vitamin C, while fat-soluble vitamins include vitamins A, D and K.

Water-soluble vitamins, known as hydrosolubles, are mainly absorbed in the small intestine, and enter the bloodstream to be transported to the body’s tissues. These vitamins are not stored in the body in large quantities, and get easily eliminated through urine if there are too many of them, so it is important to support your daily diet with vitamin supplements to ensure the body functions healthily.

Fat-soluble vitamins, called liposolubles, require the presence of fats and digestive enzymes to be better absorbed by the body. For greater absorption or assimilation by the body, we therefore recommend eating foods containing healthy fats such as avocados, fish and nuts, to absorb more vitamins.

What vitamins should I take?

The human body needs 13 vitamins to be able to perform all its functions properly.1 If any of these vitamins is lacking, the body begins to present symptoms of deficiency, and this can be extremely dangerous.

Vitamin A

This vitamin can be found in two different natural forms: preformed vitamin A in animal products, and provitamin A in plant-based foods – the best-known of these being beta carotenes.

Some signs of vitamin A deficiency include problems with skin dryness that may evolve into eczema.3 Vitamin A deficiency can also worsen problems with vision or dry eyes, among other issues.

Vitamin B

The purpose of group B vitamins is to keep the body healthy. Group B vitamins are divided into 11 numbered classifications, 8 of which are essential for the body.9 Read on for a brief description of each one:

  • B1 (thiamine): Vitamin B1 deficiency can lead to problems with nervous system function and normal heart function.
  • B2 (riboflavin): Vitamin B2 needs to be absorbed for the body to properly metabolise iron, and deficiency leads to nutritional problems such as anaemia
  • B3 (niacin): Lack of vitamin B3 can cause alterations in the mucous membranes, vomiting, constipation or diarrhoea, loss of appetite, rashes, or skin discolouration, as well as impaired psychological function.
  • B5 (pantothenic acid): Vitamin B5 is found in broccoli, sweet potatoes, certain mushrooms, cereals and grains, and its benefits include preventing headaches and gastrointestinal problems associated with vitamin deficiency.
  • B6 (pyridoxine): Vitamin B6 deficiency can have undesired effects on hormone regulation and the synthesis of steroid hormones, vitamin D, and other neurotransmitters. It can cause peripheral neuropathy, seizures, anaemia and depression.
  • B7 (biotin): Also known as vitamin H, vitamin B7 is a crucial nutrient for taking care of hair, skin, eyes and liver.
  • B9 (folic acid): Vitamin B9 plays an important role during pregnancy, reducing the likelihood of neural tube defects in the foetus. This stems from its role in DNA protection and the formation of red blood cells.
  • B12 (cobalamin): Vitamin B12, found in animal foods, is necessary for the formation of red blood cells. Vitamin B12 deficiency can cause anaemia.

Vit B

Vitamin C

Also called ascorbic acid, vitamin C is vital for the metabolism of proteins.1 It can be found in large numbers of fruits and vegetables such as oranges, grapefruits, peppers, kiwis and broccoli.

The benefits of vitamin C include:

  • Improving collagen production
  • Supporting a healthy immune system
  • Protecting cells from oxidative damage (as an antioxidant) and wound healing
  • Reducing fatigue

Vitamin C deficiency can lead to scurvy disease, poor gum health, and a weakened immune system.

Vit C

Vitamin D

This is the vitamin for which most people around the world, and across all age groups, develop deficiencies.7 The main problem is that almost no food can efficiently supply the daily vitamin D requirements for adults.

That’s why a good amount of sun exposure is recommended. However, researchers can’t agree on the right level of exposure, because of the risk of diseases such as skin cancer when trying to get the right amount of sun.

However, there are Vitamin D supplements available that allow the body to obtain adequate levels of this vitamin. This prevents bone problems, drastic mood swings, muscle pain, and growth problems in children.

Vitamin K

Vitamin K is mainly found in plant-based foods. Its main function is to regulate blood clotting and it is therefore important to the health of the heart and bones.4

Vitamin K deficiency is extremely dangerous, since an injury could cause internal bleeding. Similarly it means more blood than usual will be lost if a cut in the skin occurs, before the wound is closed up.

Vegetable vitamin D3

25 μg (1000 IU) / 60 capsules

14,00 €

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Vitamin K2

105 μg / 60 capsules

21,00 €

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Organic Acerola

170 mg / 60 tablets

24,00 €

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Vitamin A (Retinol)

16 mg / 60 capsules

17,00 €

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Vitamin D3

5 μg (200 IU) / 60 capsules

14,00 €

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Vitamin B-Complex

200 mg / 30 capsules

19,00 €

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  1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6099991/
  2. https://health.gov/dietaryguidelines/2015/resources/2015-2020_Dietary_Guidelines.pdf
  3. https://pubmed.ncbi.nlm.nih.gov/25277487/
  4. https://ods.od.nih.gov/factsheets/VitaminK-HealthProfessional/
  5. https://www.cdc.gov/ncbddd/vitamink/facts.html
  6. https://www.healthline.com/health/food-nutrition/vitamin-e-deficiency/
  7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6129797/
  8. https://ods.od.nih.gov/factsheets/VitaminC-Consumer/
  9. https://www.healthline.com/health/food-nutrition/vitamin-b-complex#_noHeaderPrefixedContent

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