Writing within the journal Naunyn-Schmiedeberg’s Archives of Pharmacology, researchers from the Hannover Medical College in Germany in contrast the local weather wherein vitamin C dietary supplements are offered in that nation and america. The aim was to find out what customers can anticipate when taking the obtainable merchandise, particularly concerning the transparency of vitamin dosage and security info.
“Greater than three quarters of merchandise exceed the really useful day by day dose for vitamin C-containing dietary dietary supplements and almost 40% of all preparations transgress a possible higher security degree,” the researchers wrote. “The day by day doses taken within the type of vitamin C dietary supplements are sometimes excessive, and customers usually are not knowledgeable correctly.”
Vitamin reputation
Complement use in Germany is common as one in three folks within the nation take a nutraceutical. In america, the quantity is increased. In line with the Nationwide Heart for Well being Statistics, greater than 57% of U.S. residents take dietary supplements often. In 2023, Grand View Analysis valued the worldwide dietary complement market at $177.5 billion.
Vitamin C is among the most consumed dietary dietary supplements, thought-about the third hottest in Germany. For American customers, it’s the sixth hottest complement amongst all dietary supplements taken. The demand for the vitamin rises throughout winter and chilly season due to the widespread, but unsubstantiated notion that it could actually rapidly stymie colds and flu-like circumstances.
Also referred to as ascorbic acid, vitamin C is water soluble and consequently has restricted storage potential within the human physique. Folks can not synthesize the vitamin by themselves and wish to fulfill their day by day vitamin C requirement by way of weight loss program. The vitamin is important for a lot of very important bodily features, serving as an antioxidant.
“Other than this, vitamin C is a co-factor for the synthesis of collagen, carnitine and sure hormones like adrenaline and noradrenaline,” the researchers defined. “By affecting gene transcription, vitamin C additionally performs a job in epigenetic processes.”
Vitamin C is moreover wanted for iron absorption, decreasing ferric iron within the gastrointestinal tract. It performs an essential function by instantly influencing the quantity of iron absorbed by means of weight loss program.
In line with the research, the U.S. Meals and Drug Administration and Germany’s Bundesinstitut für Risikobewertung advocate 90 to 110 mg of vitamin C day by day for optimum organic perform. As indicated by the European Meals Security Authority and the U.S. Nationwide Institutes of Well being, the higher consumption degree for vitamin C ranges from 1,000 to 2,000 mg, although bioavailability happens at doses of 100 to 400 mg.
Examine particulars
The researchers analyzed 106 dietary supplements offered by on-line shops in Germany (n = 66) and america (n = 40). A limitation of the research was that researchers didn’t study a higher variety of vitamin C dietary supplements.
Monopreparations had been sometimes extra common amongst customers than mixture preparations, although the researchers discovered that greater than one-third of all dietary supplements contained energetic elements apart from vitamin C.
“Mixture preparations can pose a well being danger in two methods,” the researchers wrote. “Firstly, some components could also be added at a dosage that exceeds the protected higher tolerable degree of the respective ingredient. Fats-soluble nutritional vitamins akin to vitamin A, D and E possess a better danger of overdosing, as they will accumulate contained in the human physique. Secondly, because the components usually are not the main focus of the complement, some customers may not concentrate on the truth that they’re taking them in any respect. Even when every additive is included at a protected dose individually, if a number of dietary dietary supplements are consumed directly, this will add as much as a dosage that exceeds protected ranges.”
They indicated that imply day by day doses of the merchandise studied will possible not result in opposed outcomes amongst wholesome people however might be unsafe for individuals who have a historical past of kidney stones.
Solely three out of the 106 merchandise had a warning a few potential laxative impact. When it got here to product labeling, 5 to twenty% of merchandise had been lacking warnings that had been both really useful or legally required.
Additionally, listed dosages had been generally completely different than what the product contained.
“Of all merchandise included on this evaluation greater than three quarters transgress the really useful day by day dose for dietary dietary supplements… It’s value noting that no U.S.-American establishment made a suggestion for dietary supplements particularly, however as a substitute solely listed the higher restrict of vitamin C as 2,000 mg,” the researchers famous. “This will clarify why U.S.-American merchandise usually possess increased doses and extra ceaselessly cross a day by day dose of 1,000 mg.”
Supply: Naunyn-Schmiedeberg’s Archives of Pharmacology. doi: 10.1007/s00210-025-04248-y. “Market evaluation of vitamin C-containing dietary dietary supplements in Germany and the USA: Shopper info and dangers and advantages”. Authors: J. Decke, R. Seifert
