生物与医学2014csanr.wsu.edu
有机作物具有更高抗氧化物、更低镉和更低农药残留
Higher antioxidant, lower cadmium, and lower pesticide residues in organic crops
入门 · 约 45 分钟读完前置知识：荟萃分析基础、营养流行病学常识
导读
这篇论文是一项基于 343 篇同行评审文献的荟萃分析，研究有机作物与常规种植作物在营养成分上的差异。结论显示有机作物抗氧化物含量显著更高，而镉和农药残留更低，与此前认为有机食品无营养差异的综述结论相左。
HN 关注点：该结论与 2012 年斯坦福大学'有机食品并无健康益处'的研究直接矛盾，HN 读者围绕荟萃分析方法与'有机'定义的严谨性展开讨论。
HN 评论精选
这几条评论里：质疑 2 补充 1 亲历 1
质疑指出该研究与斯坦福 2012 年结论相矛盾
这不是和斯坦福 2012 年的研究直接矛盾吗？该研究发现有机产品的维生素含量没有一致差异，只有磷显著更高（但磷缺乏很少见，临床意义不大）；牛奶的蛋白质和脂肪含量也无差异，仅有限证据表明有机牛奶的 omega-3 脂肪酸可能更高。
byerley查看英文原文
Isn't this directly at odds with the Stanford study from 2012? - http://med.stanford.edu/news/all-news/2012/09/little-evidence-of-health-benefits-from-organic-foods-study-finds.html "No consistent differences were seen in the vitamin content of organic products, and only one nutrient — phosphorus — was significantly higher in organic versus conventionally grown produce (and the researchers note that because few people have phosphorous deficiency, this has little clinical significance). There was also no difference in protein or fat content between organic and conventional milk, though evidence from a limited number of studies suggested that organic milk may contain significantly higher levels of omega-3 fatty acids."
质疑质疑'有机'定义模糊，荟萃分析分类标准不严谨
'有机'这个词的问题在于它宽泛且定义不清，就像我们行业里的'敏捷'。各国标准不一且随时间变化，而这份数据涵盖多国、长时间跨度，'有机'的分类高度不一致。论文对如何分类着墨很少，似乎直接采信了原始数据的说法。很多'合成'化合物在化学意义上其实也是有机的，人工处理到什么程度算合成？粪肥、堆肥与化肥的界限因国家/法律/标准而异。比如论文把'生物动力'也算作有机，而那更像是把灵性混入农耕的炼金术。这个问题与'天然 vs 标准医学'之争重叠，充满污染信息的伪科学。
SigmundA查看英文原文
The problem with the term "organic" is it's broad and not well defined. It's like "agile" in our space. There are some standards varying by country some government enforced some not, and those standards have changed over time. This data seems to encompass data from many countries over a long period of time. This means how something is classified in the organic bin or not in highly inconsistent in the data set. The paper seems thin on how they classified the data as organic or not, looks like they took that source data's word for it. I am very skeptical anytime someone uses such vague terminology such as organic. Most compounds considered "synthetic" are technically organic in a chemical sense. When does something become synthetic? After all many forms chemical synthesis involves basic forms of human preparation (mechanical separation and cooking). How much human modification of a raw material crosses the line into syntheses? Manure vs compost vs fertilizer. The distinction varies by country/law/standard/organization/person. For instance the paper says they included "biodynamic" techniques as organic. Never heard of this before, looking into it it seems akin alchemy, mixing spirituality with farming protocols. The "natural" vs standard medicine debate overlaps in many way with this issue and is full of pseudoscience that pervades and pollutes the information available.
补充补充说明这是基于 343 篇文献的荟萃分析
这不是新研究，而是对已有研究的荟萃分析：'消费者对有机食品更营养的认知部分推动了需求，但科学界对是否存在显著营养差异意见不一，近期两篇综述认为没有差异。本研究基于 343 篇同行评审文献进行荟萃分析，表明有机与非有机作物在成分上存在统计显著且有意义的差异。'
jayvanguard查看英文原文
It looks like it is not a new study but rather a meta-analysis of existing studies: "Demand for organic foods is partially driven by consumers’ perceptions that they are more nutritious. However, scientific opinion is divided on whether there are significant nutritional differences between organic and non-organic foods, and two recent reviews have concluded that there are no differences. In the present study, we carried out meta-analyses based on 343 peer-reviewed publications that indicate statistically significant and meaningful differences in composition between organic and non-organic crops/crop-based foods."
亲历亲历：担忧大公司通过立法打压本地有机种植
我们住的亚利桑那中部山区本地有机食品供应不错。别人买不买有机食品我无所谓，但有一点例外：给本地种植食品设置法律障碍的做法。几年前，我们的参议员 Jon Kyle 在收了孟山都大额竞选捐款后，提交了由孟山都起草的食品安全法案，会让家庭菜园、社区花园和小型种植者像数十亿美元的食品公司一样层层过关——我认为这是在迫使人们从大型食品集团购买。
mark_l_watson查看英文原文
I am generally pleased with the good availability of locally grown organic food where we live in the mountains of Central Arizona. If people don't want organic food, I could generally care less except for one thing: efforts to put legal roadblocks in the way of locally grown food. For example: A few years ago our Senator Jon Kyle, after taking large campaign contributions from Monsanto, submitted the American Food Safety bill that was prepared by Monsanto. This Bill would make home gardeners, local community gardens and small local growers jump through the same hoops as the multi billion dollar food corporations. I believe that it was generally accepted that this was an attempt to force people to buy from the large food conglomerates - at least that is my belief.
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- 2014Hacker News 讨论帖306 分 · 203 评
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