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Suzanne Huurman saw a lot happen at Real Madrid, where she worked as a sports doctor between 2020 and 2024. The entire range of supplements and vitamins, including caffeine tablets, proteins, carbohydrate products, electrolytes, magnesium, vitamins C and D, Omega 3, probiotics and collagen. “Supplement has been widely normalized in professional football for years,” she says. “At Real Madrid, a lot was used. The richer a club, the more is taken.”
Renter, now working as, among other things match doctor for world football association FIFA, it is therefore not surprising that Ajax, after previously including PSV and the Dutch swimming association, recently concluded a deal with a supplement company. Vitakruid, a family business from Hillegom, has been the ‘Official Nutrition Supplier‘ of the club.
The impression is given that this is more than a normal sponsorship deal. Vitakruid will “provide Ajax with high-quality supplements” and develop them “specifically” for the club, according to a recently published press release in which, in addition to the commercial director, Martijn Redegeld, head of top sport, is quoted. Redegeld, himself a sports nutritionist and previously employed by the sports umbrella organization NOC-NSF and the Jumbo-Visma cycling team, speaks of “access to expertise and products that match our philosophy.”
Criticism soon followed the announcement. For example, Nico Terpstra, general practitioner and former chairman of the Association against Quackery, called the company on LinkedIn a “scary and controversial vitamin and supplement pusher”. And in Fidelity Science journalist Adriaan ter Braack, known as Sjamadriaan, wrote in his column that “crazy nonsense” Vitakruid is “trying to legitimize” itself through this deal with Ajax. Where does that criticism come from? What kind of company is Vitakruid? And what role will they play at Ajax?
Orthomolecular therapy
Elly Korzelius started Vitakruid in 2000 from a “practice in nutrition and Traditional Chinese Medicine,” states the company website. She was also involved in orthomolecular therapy. This is (according to the Nutrition Center, scientifically not proven) naturopathy that searches for ‘optimal concentrations’ of nutrients in the body, including through supplementation. Three years after the founding of Vitakruid, Korzelius launched its own brand products, including ‘Buffered Vitamin C’ and ‘Magnesium Taurate’. Their house in Hillegom was “full” of them, according to the website, although sales were “slow”.
From 2015, her son, Bob van Inge, took over the management “step by step” and Vitakruid grew rapidly in line with the entire supplement industry. According to the site, “an average of 50 percent per year.” The company is very profitable: in 2023, more than 10 million profit was made on a gross operating result, a derivative of the turnover (which the company does not publish), of almost 25 million euros, according to the latest annual accounts filed with the Chamber of Commerce. A year earlier, this was still 5.6 million on a gross operating result of 16.4 million euros.
The company owes the growing popularity of Vitakruid largely to collaboration with influencers who promote and sell the products online. Top athletes such as hockey player Yibbi Jansen and kickboxer Levi Rigters are ‘ambassadors’, as was Arie Boomsma.
But this collaboration with influencers is also a source of criticism. For example, science journalist Ter Braack has regularly pointed out unscientific statements made by Vitakruid sellers and ambassadors, for example about controversial ‘solar training’.
Or take an orthomolecular dietician who posted about the anti-childhood vaccination book Vaccine free! and warned about laptop and telephone radiation, including in unborn babies. In response to NRC she says that these statements can no longer be seen online. According to her, Vitakruid never confronted her about these types of statements. NRC made inquiries with the company, but no response was received on this specific point. Because the woman says she has been threatened because of controversial statements she made in the past, she asked not to be named. Her name is known to the editors.
It also happens that influencers promote Vitakruid products in ways that are not permitted. NRC submitted a number of posts to the Dutch Food and Consumer Product Safety Authority (NVWA), such as that of a nutrition coach who recommended the Vitakruid product Collagen Solugel Matcha in her webshop in October as a contribution to “strong joints and connective tissue”. That is not allowed, says an NVWA spokesperson. It is prohibited to claim that supplements have health benefits unless there is scientific evidence for this and the European Union has approved such a claim. This is not the case in the case of collagen.
‘Serious deception’
Influencers are responsible for their own advertising texts, but Vitakruid was also reprimanded by the NVWA last year for “serious misleading” in statements about collagen. Vitakruid stated that collagen is important for all kinds of functions in the body, such as ligaments, blood vessels and bones, and that the substance can be supplemented with a supplement. Also a prohibited health claim, according to the NVWA. Other companies, including Kruidvat and Holland & Barrett, were also fined for serious deception.
The text on the Vitakruid website has been adjusted. But it still says that “much scientific research has been done” into the appropriate dosage of collagen supplements. That is also not allowed, a spokesperson for the NVWA told NRC. “Because no claim has been scientifically proven, it cannot be stated that a certain dosage contributes to the desired effect.” This statement was also submitted to Vitakruid, but the company did not respond substantively.
Vitakruid products are still recommended and sold by influencers on Instagram and Tiktok. But the company has now gone one step further. Their supplements are now also available in Albert Heijn stores. A deal with Ajax seems to fit this next phase.
“Sports is of course a rewarding market for these companies,” says Floris Wardenaar, sports nutrition scientist at Arizona State University in Phoenix. Also Renger Witkamp, professor nutritional biology at the university in Wageningen (WUR), understands why Vitakruid would like to collaborate with Ajax. Such a large professional club has a “halo of health”, he says. “That is very interesting commercially.”
Sports is of course a rewarding market for these types of companies.
But what can Vitakruid do for Ajax? Witkamp is skeptical about that. Scientifically, there is little basis for the idea that footballers need a range of supplements, he says. Extra protein can contribute to recovery and strength training. “This also partly applies to creatine, but it sometimes also causes weight gain.”
And caffeine is widely used in professional football, says sports doctor Huurman, who previously also worked at Go Ahead Eagles and PSV. “Like for increasing alertness.” Any iron deficiencies, for example in vegetarians, can be supplemented with a supplement, says Witkamp. “And finally, you see that beetroot juice and beta-alanine are used. These could improve endurance. But I doubt whether well-trained football players will notice anything.”
Football is not as extreme a sport as cycling, for example, where large amounts of energy are consumed and there is less room for fruit and vegetables, says Witkamp. “A multi-vitamin can be useful there.” But for a football player, provided he or she has a healthy diet, and that seems likely at a club like Ajax that employs sports dieticians and chefs, he believes this is not necessary.
That is also the core of the criticism of the supplement industry: those who eat a varied diet almost never need extra vitamins or minerals, says Witkamp. With exceptions, such as folic acid during pregnancy and vitamin D in winter for darker skin. And the reasoning ‘if it doesn’t help, it doesn’t hurt’ does not always apply: for example, former skater Sven Kramer suffered a leg injury in 2010 due to excessive doses of vitamin B6.
The other group of supplements, based on herbal extracts or ingredients such as collagen, has virtually no scientific evidence that they work, says Witkamp.
Yet, to the annoyance of science journalist Ter Braack, Vitakruid recommends supplements to seemingly everyone in advice on its own website, regardless of lifestyle, age, or other variables. At least that’s his experience, he says, after completing an online “vitamin test” that the company offers. “I have tried it many times. You can fill it in as if you are doing everything perfectly and you will still be prescribed supplements.” NRC asked Vitakruid whether there are scenarios in which this does not happen, but did not receive an answer to that question.
Through the deal with Ajax, Vitakruid commits itself to a global brand with strong credibility and a huge fan base. Food scientist Wardenaar says he was “surprised” by the news of the collaboration between Ajax and Vitakruid. “Ajax is seen as a top club. It would be nice if the partners they work with are of impeccable behavior.” And he does not think it is good for a club to commit itself to one commercial party: this means that the supplement advice for the players is “clouded” by sponsor interests.
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