What is the most important daily vitamin

Vitamin C - surprisingly healthy?

What is behind the advertising claims about vitamin C-containing food supplements?

Food supplements containing vitamin C usually contain between 50 mg and 1000 mg of vitamin C, but some are also extremely dosed in much higher amounts. They are often offered in combination with zinc and selenium or iron, beta-carotene or vitamin E. The manufacturers recommend the products "for smokers", "in cold, wet weather" or "stress". When marketing these products, only certain health-related statements may be made. These statements are precisely defined at the European level.

For vitamin C are i.a. the following health-related advertising statements are allowed, published in the Official Journal of the European Union:

  • Vitamin C contributes to the normal function of the immune system during and after intense physical activity.
  • Vitamin C contributes to normal collagen formation for the normal function of blood vessels (bones, cartilage function, gums, skin, teeth).
  • Vitamin C contributes to normal psychological function.
  • Vitamin C contributes to the normal function of the immune system.
  • Vitamin C helps protect cells from oxidative stress.
  • Vitamin C helps reduce tiredness and fatigue.
  • Vitamin C increases iron absorption.
  • Vitamin C contributes to the regeneration of the reduced form of vitamin E.

Most of the time, these statements are only about maintaining normal functions, not improving function. Here is a complete listing of the allowed statements.

The often propagated precautionary intake of vitamin C to prevent or alleviate the course of the disease from colds could not be proven after evaluating various studies. Exceptions could possibly be people under extreme physical strain (marathon runners, skiers, soldiers) or in very cold surroundings.

Press reports on the treatment of Covid 19 with vitamin C are clinical studies on seriously ill patients who are given high-dose vitamin C (drug!) As an infusion. It remains to be seen whether this will be successful. Vitamin C as a dietary supplement does not protect against infection with the corona virus (Sars Cov 2).

What should I look out for when using products containing vitamin C?

Vitamin C is considered harmless. It is soluble in water and is excreted in the urine and feces. An intake of vitamin C in excess of what is required is of no benefit. Once saturation is reached, it is no longer possible to record.

The European safety authority EFSA assumes that no harmful side effects are to be expected from a daily intake of up to 1 g of vitamin C (in addition to food). The Federal Institute for Risk Assessment recommends a maximum amount in food supplements of 250 mg / day.

However, a very high dose of 3 to 4 g / day can lead to flatulence and diarrhea. It is discussed whether the oxalic acid that is formed when ascorbic acid is broken down leads to kidney and bladder stones (oxalate stones) in the event of a permanent, heavy overdose. The Association of German Internists (BDI) therefore recommends that people who tend to develop kidney stones or who have already had kidney stones do not regularly take high-dose vitamin C supplements (> 1 g / day).

It is important to ensure that the ascorbic acid does not stay too long in the mouth, as this can lead to acid-related corrosion of the tooth enamel.

Those who store too much iron for hereditary reasons (iron storage disease, hemochromatosis) should consume a maximum of 500 mg of vitamin C per day (including food) and take at least 2 hours away from meals containing iron or meat. And do not use dietary supplements containing vitamin C without first consulting your doctor.

What does the body need vitamin C for?

The water-soluble vitamin C, also called ascorbic acid, is vital and has many different tasks. It releases electrons and traps free radicals like reactive oxygen molecules, so it has antioxidant effects, i.e. it reduces oxidative damage in the body. Vitamin C plays a key role in the development of collagen (connective tissue, cartilage and bones), carnitine and hormones. It promotes iron absorption and inhibits the carcinogenic nitrosamine formation.

The recommended vitamin C intake for men is 110 mg / day, for women 95 mg / day. 105 mg / day is recommended for pregnant women and 125 mg / day for breastfeeding women. The metabolic losses and safety margins are taken into account in these values. A fasting plasma concentration of ascorbate of 50 µgmol / l should be guaranteed.

There is a peculiarity with smokers. You have higher metabolic vitamin C losses. Male smokers are therefore recommended 155 mg vitamin C / day, female 135 mg / day.

The supply situation for the population is good, especially since ascorbic acid is also used in a variety of ways as an additive. Causes of a deficiency can be: one-sided diets without fruit and vegetables, alcoholism, prolonged exposure to extreme cold, chronic illnesses and constant use of medication (cortisone, acetylsalicylic acid ASA).

The classic vitamin C deficiency disease "scurvy" can be prevented with just 10 mg vitamin C / day and therefore hardly ever occurs at all. Slight deficiencies can manifest themselves through general tiredness, muscle weakness, susceptibility to infection, iron deficiency and poor wound healing.

Can I cover my daily requirement with food?

Vitamin C (ascorbic acid) occurs naturally in almost all animal and vegetable foods. The average daily requirement of 100 mg is easy to achieve with fresh fruits and vegetables. The daily requirement is already covered with approx. 200 g of kiwi or orange.

Rose hips (1250 mg vitamin C / 100 g) or black currants (177 mg vitamin C / 100 g) are extremely rich in vitamin C, but they are rarely consumed by the population. However, potatoes are often eaten. One serving (300 g) of boiled potatoes is 45 mg. One serving of broccoli (200 g) contains 180 mg of vitamin C.

Vitamin C is very sensitive to heat and light. The content in a food depends on the time of harvest, transport, duration and type of storage as well as the preparation in the kitchen. A raw red pepper contains 140 mg of vitamin C per 100 g, while in the steamed state there are "only" 110 mg of vitamin C / 100 g.

Some amounts are also ingested through processed foods. In the food industry, ascorbic acid is used as an additive (antioxidant and color stabilizer E 300 to 304, 315, 316). For example, apple juice should not turn brown and the sausage should be nice and red. It inhibits the formation of nitrosamines in cured products and improves the properties of the dough in flours. The additive is used in canned fruit and vegetables, frozen or dried potato products, fruit juices and nectars, jam, jam, jelly, meat and sausage products, fish products as well as bread and baking mixes.

  • It makes sense to eat vegetables and fruits as raw vegetables, as vitamin C is sensitive to heat and light.
  • Avoid long holding times.
  • Since there is a particularly large amount of vitamin C under the peel, we advise you to eat it - well washed.

These vitamin compounds are approved for vitamin C in food supplements in Germany and other EU countries in accordance with EU Directive 2002/46 / EC, Annex II (version dated July 5, 2017):

  • L-ascorbic acid
  • Sodium L-ascorbate
  • Calcium L-ascorbate
  • Potassium L-ascorbate
  • L-ascorbyl-6-palmitate
  • Magnesium L-ascorbate
  • Zinc L-ascorbate


BfR (2021): Updated maximum quantity proposals for vitamins and minerals in food supplements and fortified foods
Opinion No. 009/2021 of March 15, 2021

BfR (2021): Maximum amount proposals for vitamin C in food including food supplements

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K. Biesalski et al .: Nutritional Medicine, Thieme Verlag, 2010

PM Suter: Checklist Nutrition, Thieme Verlag, 2002

Official Journal of the European Union, Regulation No. 432/2002 of the Commission of May 16, 2012 establishing a list of permissible health-related claims about food other than information about reducing the risk of illness and the development and health of children.

DIRECTIVE 2002/46 / EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 10 June 2002 on the approximation of the laws of the member states relating to food supplements

Max Rubner Institute, Federal Research Institute for Nutrition and Food 2008, National Consumption Study II, Part 2

Berufsverband Deutscher Internisten e.V .: Vitamin C pills can increase the risk of kidney stones Vitamin C pills can increase the risk of kidney stones, news from 03/11/2013