The analysis sample included 5, boys and 6, girls. Height by age was the same as in Mean final height was The educational levels of both children and their parents are positively correlated with mean height. Since , differences between geographical regions have decreased but not vanished, with the northern population being the tallest.
The Dutch may have reached the optimal height distribution. Alternatively, growth-promoting environmental factors may have stabilized in the past decade, preventing the population from attaining its full growth potential. Over the past decades, human height has increased in most industrialized countries.
This trend has been the result of improvements in the nutritional, hygienic, economic, and health status of the populations in question 1. Such factors may allow disadvantaged individuals in particular to grow taller. However, we have not found any reduction in height variation 2.
It appears that individuals benefit more or less equally from improvements in living conditions. Do we believe that we could all be giants if living conditions for humans were to improve further, or is there some maximum and presumably optimal population average beyond which our species will not grow, no matter how favorable the circumstances?
Although being tall is often associated with being healthy, this may not always be the case. Taller adults have, for example, higher rates of several types of cancer 3. The question of whether there is a maximum population average is almost impossible to answer, but studies of trends in mean height and of height variations in tall populations could suggest a possible direction. The Dutch population is the tallest in the world and has been well studied. Before , population height in The Netherlands was estimated on the basis of data for conscripts, i.
Between and , there were four large cross-sectional nationwide growth studies. In The Netherlands, people have been getting taller since 2 , 5. In The Netherlands, as in most Northern European countries, the upward trend is slowing down significantly 2 , 6 , and it even appears to be reversing in the United States 7.
This article presents new data about height from the Fifth Dutch Growth Study, which was carried out in If not, has there been a compression of height variation? Do geographical region and educational levels affect the development of mean height? The sample comprised of 10, children of Dutch origin and 1, imputed cases, resulting in an analysis sample of 12, children 5, boys and 6, girls aged 0—21 y. Table 1 lists the numbers of children in each age group.
Table 2 summarizes the mean and SD for height extracted from the height references, classified according to age and sex. Extended tables are available from the authors on request.
New growth diagrams were constructed for boys and girls aged 0—21 y, including 2. Figure 1a,b shows the new growth diagrams for boys and girls aged 1—21 y. Similar growth diagrams were established for children aged 0—15 mo and 0—4 y. Note that there is no visual evidence of the pubertal height growth spurt in the growth diagram for girls.
New Dutch growth diagrams, including height by age references for a boys and b girls aged 1—21 y. Figure 2 shows the trend in the mean final height in boys and girls from to The figure illustrates that the upward secular trend in the mean final height of young Dutch adults has stopped. These heights do not differ significantly from the heights in Figure 2 indicates that the pace of the increase in secular height over the years slowed down both in boys and girls, falling to almost zero in Figure 3 shows, for Dutch children aged 1—21 y, the height difference with respect to in , , , and for each age.
The figure clearly shows an increase in height for the period —, especially from the age of 4 y onward, with the increase being more marked in boys than in girls. This figure also shows that the secular trend has stopped since , not only for final height but also for all ages, with the and lines being a close match for all ages.
There is only a small difference in height at the ages of 11—13 y in boys and girls and at the age of 15 y in boys. These differences are more pronounced in boys 0. This may indicate slightly earlier puberty. Height increase since by age in Dutch a boys and b girls in solid line , striped line , dotted line , and gray striped lines. Figure 4 presents the mean height SDS of Dutch children aged 0—21 y by geographical region, level of child education, and level of parental education in and , corrected for each of the two other factors.
Variation across the geographical regions has lessened since The mean height SDS in the north and in the south are closer to the overall mean Figure 4a. This means that y-old boys and girls from the north are on average 1. Figure 4b,c shows that, in , as in , mean height SDS increased in line with the educational levels of children and their parents. Since , mean height SDS has not changed significantly.
At the age of 21 y, boys of lower-educated parents are on average 0. For girls, this difference is 0. Differences in height SDS by a geographical region, b educational level of the child, and c highest completed education of parents between open circles and filled circles. Values are means, adjusted for the effects of the other factors.
SDS, standard deviation scores. This study shows that the height of Dutch children in is very similar to that in There was a slight increase in mean height in early puberty in boys and girls, indicating that they were taller at a younger age than in However, this did not affect the final height, as no significant differences in final height were seen as compared with There was no compression of height variation observed.
It is remarkable that the secular height trend spanning y has come to an end, at least temporarily. The cause is not yet clear. Economic factors are not likely to be involved because gross domestic product in The Netherlands did not level off; indeed, it rose exponentially between and 8.
This index was established by The Netherlands Institute for Social Research to measure the progress of Dutch society using indicators that go beyond mere economic growth. The LSI rose substantially between and Between and , the differences in LSI scores between socioeconomic classes decreased. This was mainly due to a higher rise in the LSI score for lower socioeconomic groups 9. A correlation between height and LSI has not been demonstrated, but one would expect a positive correlation, as with economic growth.
The rise in LSI mentioned here and the reduction in the variation in LSI scores across socioeconomic groups do not therefore explain the break in the Dutch height trend. Children of parents born outside The Netherlands were excluded from the analyses. The so-called third-generation immigrants—those with parents born in The Netherlands but grandparents born outside The Netherlands—were not excluded.
This group makes up an increasing proportion of the population in The Netherlands but is still relatively small. Although the third-generation immigrants may be partly accountable for the flattening of the Dutch growth trend, this group is too small to fully explain the stagnation in height. Moreover, children known to have a diagnosed growth disorder or who were on growth-interfering medication were excluded from the sample.
It is possible that some growth disorders and growth-interfering medication were not mentioned by a child or parent, or were not in the medical records and therefore were missed by the health-care provider.
This could lead to an underestimation of mean height per age. However, we believe that even if we missed some children, they would form only a very small part of the sample size per age. Moreover, the same method for inquiring about and exclusion of growth disorders and medication was applied in Therefore, it is unlikely that growth disorders and growth-interfering medication influenced the height difference between and There will always be some differences in, for example, the genetic background and socioeconomic status in a given population, leading to height variations.
Given that the Dutch are the tallest people in the world, and that they are no longer growing taller, we could hypothesize that the mean height of the population has reached the maximum possible. Alternatively, growth-promoting environmental factors may have stabilized in the past decade, preventing the Dutch from fulfilling their full growth potential.
We could hypothesize that current lifestyles have a negative effect on height. For example, the high consumption of milk in The Netherlands, which has been linked to tallness 12 , declined over the past decade from 63 l per capita per year in to 60 in Unhealthy eating habits may lead to inadequate nutrient intake, which may result in lower height.
Furthermore, an unhealthy diet in combination with less energy expenditure due to a sedentary lifestyle leads to an increase in overweight and obesity, a phenomenon that has also been observed in Dutch children Higher BMI is associated with earlier onset of maturation and menarche, which, in turn, are related to lower height 15 , If our hypothesis is valid, adopting healthier lifestyles including healthier diet and more activity could result in the reemergence of the positive height trend in the future.
No pubertal height growth spurt can be observed in the growth diagram for girls. This is due to the fact that Dutch growth studies are cross-sectional studies. These growth diagrams are suitable for monitoring child height over time, but one should bear in mind that these charts do not fully represent how an individual child typically grows.
Only children with both parents born in The Netherlands were included. On the basis of data for other ethnic groups in the dataset of the Fifth Dutch Growth Study, we estimated an adjusted final height that includes other ethnic groups.
The adjusted mean final height would be These numbers are an estimate of final height for all children living in The Netherlands, irrespective of ethnicity. As the differences between the Dutch and the non-Dutch groups are substantial, separate growth references were constructed for children of Moroccan and Turkish decent, the two largest minorities in The Netherlands. These will be presented elsewhere. We found that the height difference between the north and the south of The Netherlands has diminished since This was seen irrespective of child and parental educational levels.
This change could be explained by factors such as fewer health inequalities or changes in national motility, in other words more migration between geographical regions.
However, we found no evidence indicating a reduction of health inequalities between these regions, and there have been no major shifts in motility in The Netherlands since that could explain the phenomenon Volume XXII. Tall, Taller, Tallest. Oxford Academic.
Google Scholar. Cite Cite H. Select Format Select format. Permissions Icon Permissions. Article PDF first page preview. Issue Section:. You do not currently have access to this article. Download all slides. Sign in Don't already have an Oxford Academic account? You could not be signed in. Akasaka said:. Click to expand To me, he's the taller and the tallest. I suspect the comparative form only requires two people.
That said, I think "taller" is the best choice as well. But in any event, you will likely hear both from native speakers, depending on region and level of language. Avignonais said:. You mean "taller" is the better choice. I'd use either interchangeably. Thank you, guys. So I understand.
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