International Institute of Social History, Amsterdam, The Netherlands.
Econ Hum Biol. 2012 Jul;10(3):299-309. doi: 10.1016/j.ehb.2011.08.003. Epub 2011 Aug 17.
The positive relationship between per capita availability of dairy products and average height found in historical studies (for instance in nineteenth century Bavaria, Prussia and France; Baten, 2009) does not necessarily indicate a causal relationship. Historical studies usually apply non-experimental methods that may produce substantial bias. Modern experimental controlled studies may provide high quality evidence supporting a causal relationship between consumption of dairy products and physical growth. This paper provides a systematic review and meta-analysis of controlled trials investigating the effect of supplementing usual diet with dairy products on physical growth. Twelve studies provided sufficient, independent data for meta-analysis. Seven studies were conducted since the 1990s. The other studies were conducted between 1926 and 1980. Studies were conducted in Europe, USA, China, Northern Vietnam, Kenya, Indonesia and India. Many studies had some internal validity problems such as lack of randomisation or dissimilarity of groups at baseline regarding height and age, which affects the quality of evidence. Meta-analysis and sensitivity analysis showed that the most likely effect of dairy products supplementation is 0.4 cm per annum additional growth per ca 245 ml of milk daily. Meta-regression analysis indicated that milk might have more effect on growth than other dairy products while lower height-for-age and being a teenager increased the effect of supplementation. In conclusion, there is moderate quality evidence that dairy products supplementation stimulate linear growth supporting hypotheses that changing levels of consumption of dairy products in the 19th and 20th centuries contributed to trends in height.
历史研究（例如在 19 世纪的巴伐利亚、普鲁士和法国；Baten，2009 年）发现，人均乳制品供应量与平均身高之间存在正相关关系，但这并不一定表明存在因果关系。历史研究通常采用可能产生大量偏差的非实验方法。现代实验对照研究可能提供高质量的证据，支持乳制品消费与身体生长之间存在因果关系。本文对调查补充乳制品对身体生长影响的对照试验进行了系统评价和荟萃分析。有 12 项研究提供了足够的、独立的数据进行荟萃分析。其中 7 项研究是在 20 世纪 90 年代以后进行的。其他研究则在 1926 年至 1980 年之间进行。研究地点在欧洲、美国、中国、北越、肯尼亚、印度尼西亚和印度。许多研究存在一些内部有效性问题，例如缺乏随机分组或在身高和年龄方面基线组之间的差异，这影响了证据的质量。荟萃分析和敏感性分析表明，乳制品补充的最可能效果是每天每 245 毫升牛奶额外增加 0.4 厘米的生长。元回归分析表明，牛奶对生长的影响可能大于其他乳制品，而身高年龄较低和处于青少年时期则会增加补充的效果。总之，有中等质量的证据表明，乳制品补充剂可以刺激线性生长，支持了这样的假设，即在 19 世纪和 20 世纪，乳制品消费水平的变化导致了身高的增长趋势。
