The professor is probably well known to forum members from his frequently referenced paper, "The Many Faces Of Cobalamin (Vitamin B12) Deficiency" ncbi.nlm.nih.gov/pmc/articl...
He also writes a blog. The first paragraph of the blog post "Bumblebees With B12" reads:
"It was bumblebees again (“Troubles in Paradise”) in the Netherlands. In this case around Vitamin B12 and specialized clinics. Colleague GP Leenstra does not have a good word for it. He has spoken with internists and clinical chemists, and his opinion - published in de Volkskrant - is clear. B12 deficiency exists, and should be treated properly, but B12 injections are not a panacea for 'everything'. He concludes that specialized clinics prescribe B12 injections to everyone passing through. A fantastic revenue model, he thinks. Costs of 1200 Euro per patient for 'society'. Even Long-Covid patients sometimes get B12 injections. Oh dear. I am going to try in this piece to discuss some of the points that have been raised."
The clinic in the Netherlands mentioned in the article is the one my niece was referred to with her daughter after GP / huisarts did a blood-test and B12 deficiency was diagnosed . Her diagnosis there was thorough and in the end injections were started . She is now an active young adult and studying law to become a prosecutor. My niece also asked her son to be referred. Her son was not growing as is normal for his age even after many years being treated at a university hospital, where his vitamin deficiencies had only been treated by putting him on an extra liquid vitamin/ mineral diet. I had read an article about growth and b12 and made the suggestion to take him to see the same doctor who treated her daughter for B12 deficiency. Since treatment started with her son he has grown more than 10 cm so far. All her 3 children were in the end diagnosed and are being treated just like my daughter and I are , after we were diagnosed in the U.K. years before. More family have been diagnosed, it does seem to be a genetic problem.
If I am remembering properly I believe the the original Could It be b12 video talks about the lack of growth due to the deficiency - let me try to find it.
Thanks for sharing this. There was a big stink recently about b12 clinics in the Netherlands and one professor Leenstra published his idiotic impression of the clinics in a national newspaper. Which basically suggested that the clinics were profiting from people and giving b12 to anyone who asked. So it’s really good to read this well balanced and expert response by Dr Wolfenbuttel (apparently sadly retired now). Thanks for sharing
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JFK - Kennedy and B12
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