Introduction of oral vitamin D supplementation and the rise of the allergy pandemic
Matthias Wjst
Abstract
The history of the allergy pandemic is well documented, enabling us to put the vitamin D hypothesis into its historical context. The purpose of this study is to compare the prevalence of rickets, vitamin D supply, and allergy prevalence at 50-year intervals by means of a retrospective analysis of the literature since 1880. English cities in 1880 were characterized by an extremely high rickets prevalence, the beginning of commercial cod liver oil production, and the near absence of any allergic diseases. By 1930 hay fever prevalence had risen to about 3% in English-speaking countries where cod liver oil was preferentially used for the treatment of rickets. In 1980 vitamin D was used nation-wide in all industrialized countries as supplement to industrial baby food, thus eradicating nearly all cases of rickets. At the same time the allergy prevalence reached an all-time high, affecting about 30% of the population.
Time trends are therefore compatible with the vitamin D hypothesis although direct conclusions cannot be drawn. It is interesting, however, to note that there are at least two earlier research papers linking synthesized vitamin D intake and allergy (Reed 1930 and Selye 1962) published prior to the modern vitamin D hypothesis first proposed in 1999.
The vitamin D allergy hypothesis attributes the initial sensitization against allergens during the newborn period to immunological side effects of vitamin D supplements used for rickets prevention. The increasing interest in the vitamin D hypothesis is understandable because all otherhypotheses about the origin of the allergy epidemic have largely failed to provide any clear answers. Moreover, none of the current hypotheses have ever been tested for compatibility with the historical development of the allergy pandemic.
It may therefore be interesting to examine historical data on vitamin D intake and prevalence of allergy. As chosen method, a systematic analysis of articles published in Pubmed since 1950 was combined with a full-text search of all issues of Science and Nature since 1869. Furthermore, current Google book content was searched in addition to a manual search of textbooks for the keywords vitamin D (and chemical analogues) and allergy between 1920 until 1950 (see also acknowledgments).
Allergic manifestations were so rare in 1880 that today they would be considered an "orphan disease". This may reflect a recognition bias in a community that was understandably preoccupied with more pressing, lifethreatening conditions such as cholera, tuberculosis, typhoid and measles. Nevertheless, allergic symptoms were clearly described at that time. The few studies on allergic diseases from the 19th century all rely on a limited number of cases. The British doctor Harrison Blackley wrote in his 1873 book "Hay Fever: Its causes, treatment, and effective prevention": "Even in this country, where the disorder probably had its commencement and where it is still more common than in any other part of Europe, there are medical men to be found who know very little about it; and on the Continent there are still some to be found who have never even heard of the disease". The origins of the disease are vague.
The first formal description of hay fever is usually ascribed to John Bostock, who presented his own case in 1819 to the London Medico-Chirurgical Society. Another description was made in 1859 when the German professor Philipp Phoebus from Giessen published the first large allergy study, which was based on 158 cases. The sample consisted of patients from many hospitals because allergy was such a rare disease. In 1876 the American physician George Beard, a contemporary of Blackley, assembled only 100 patients. At the end of the 19th century, allergy prevalence may therefore be estimated at 0.1% in England, as well as in the United States of America. In continental Europe, it was not until 1906 that the term "Allergie" was introduced by Clemens von Pirquet.
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The history of the allergy pandemic is well documented, enabling us to put the vitamin D hypothesis into its historical context. The purpose of this study is to compare the prevalence of rickets, vitamin D supply, and allergy prevalence at 50-year intervals by means of a retrospective analysis of the literature since 1880. English cities in 1880 were characterized by an extremely high rickets prevalence, the beginning of commercial cod liver oil production, and the near absence of any allergic diseases. By 1930 hay fever prevalence had risen to about 3% in English-speaking countries where cod liver oil was preferentially used for the treatment of rickets. In 1980 vitamin D was used nation-wide in all industrialized countries as supplement to industrial baby food, thus eradicating nearly all cases of rickets. At the same time the allergy prevalence reached an all-time high, affecting about 30% of the population.
Time trends are therefore compatible with the vitamin D hypothesis although direct conclusions cannot be drawn. It is interesting, however, to note that there are at least two earlier research papers linking synthesized vitamin D intake and allergy (Reed 1930 and Selye 1962) published prior to the modern vitamin D hypothesis first proposed in 1999.
The vitamin D allergy hypothesis attributes the initial sensitization against allergens during the newborn period to immunological side effects of vitamin D supplements used for rickets prevention. The increasing interest in the vitamin D hypothesis is understandable because all otherhypotheses about the origin of the allergy epidemic have largely failed to provide any clear answers. Moreover, none of the current hypotheses have ever been tested for compatibility with the historical development of the allergy pandemic.
It may therefore be interesting to examine historical data on vitamin D intake and prevalence of allergy. As chosen method, a systematic analysis of articles published in Pubmed since 1950 was combined with a full-text search of all issues of Science and Nature since 1869. Furthermore, current Google book content was searched in addition to a manual search of textbooks for the keywords vitamin D (and chemical analogues) and allergy between 1920 until 1950 (see also acknowledgments).
Allergic manifestations were so rare in 1880 that today they would be considered an "orphan disease". This may reflect a recognition bias in a community that was understandably preoccupied with more pressing, lifethreatening conditions such as cholera, tuberculosis, typhoid and measles. Nevertheless, allergic symptoms were clearly described at that time. The few studies on allergic diseases from the 19th century all rely on a limited number of cases. The British doctor Harrison Blackley wrote in his 1873 book "Hay Fever: Its causes, treatment, and effective prevention": "Even in this country, where the disorder probably had its commencement and where it is still more common than in any other part of Europe, there are medical men to be found who know very little about it; and on the Continent there are still some to be found who have never even heard of the disease". The origins of the disease are vague.
The first formal description of hay fever is usually ascribed to John Bostock, who presented his own case in 1819 to the London Medico-Chirurgical Society. Another description was made in 1859 when the German professor Philipp Phoebus from Giessen published the first large allergy study, which was based on 158 cases. The sample consisted of patients from many hospitals because allergy was such a rare disease. In 1876 the American physician George Beard, a contemporary of Blackley, assembled only 100 patients. At the end of the 19th century, allergy prevalence may therefore be estimated at 0.1% in England, as well as in the United States of America. In continental Europe, it was not until 1906 that the term "Allergie" was introduced by Clemens von Pirquet.
DOWNLOAD COMPLETE PDF HERE
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