Cappuccio F P, Rink E, Perkins-Porras L, McKay C, Hilton S, Steptoe A
Department of Community Health Sciences, St George's Hospital Medical School, Cranmer Terrace, London SW17 0RE.
Nutr Metab Cardiovasc Dis. 2003 Feb;13(1):12-9. doi: 10.1016/s0939-4753(03)80163-1.
High fruit and vegetable intake is associated with health benefits for cancer and cardiovascular disease. An increase is therefore integral in recommendations for the prevention of chronic disease. However, measuring intake requires either extensive dietary assessment or the measurement of specific bio-markers which is neither cheap nor feasible for the routine assessment of an individual's diet in a community or primary care setting. Within the context of a study evaluating a dietary counselling programme to increase fruit and vegetable intake our aim was to assess the use of a simple tool to estimate fruit and vegetable intake.
We studied associations between bio-markers [plasma ascorbic acid, beta-carotene and alpha-tocopherol 24-hour urinary potassium excretion] and a two-item fruit and vegetable consumption questionnaire in 271 subjects (105 men and 166 women), aged 18 to 70 years. After controlling for age, sex, vitamin supplement use, smoking and body mass, those reporting a daily intake of > or = 5 portions of fruit and vegetables had higher potassium excretion (difference 15.6 [95% confidence interval: 6.2 to 25.0] mmol/24 h), urinary potassium/creatinine ratio (1.2 [0.5 to 2.0]) and plasma vitamin C (10.0 [-0.9 to 20.8] mumol/L) than those reporting < or = 2.5 portions per day. beta-carotene (p = 0.04), vitamin C (p = 0.01) and potassium excretion (p < 0.001) were associated with fruit rather than vegetable intake. The two-item questionnaire had high specificity; over 3/4 of participants who reported low intake also had bio-markers below the upper third of the distribution.
Self report of fruit and vegetable intake through a simple questionnaire is confirmed by bio-markers for those eating less than five portions of fruit and vegetables a day. Although the tool is amenable to improvements for the detection of vegetable portions, it may prove useful for monitoring dietary preventive approaches in primary care without the use of invasive and costly biochemical measurements.
大量摄入水果和蔬菜对预防癌症和心血管疾病有益。因此，增加水果和蔬菜的摄入量是预防慢性病建议中的重要内容。然而，测量摄入量需要进行全面的饮食评估或测量特定的生物标志物，这对于在社区或初级保健机构中对个体饮食进行常规评估而言，既不便宜也不可行。在一项评估旨在增加水果和蔬菜摄入量的饮食咨询项目的研究背景下，我们的目的是评估一种用于估计水果和蔬菜摄入量的简单工具的实用性。
我们研究了271名年龄在18至70岁之间的受试者（105名男性和166名女性）的生物标志物[血浆维生素C、β-胡萝卜素和α-生育酚、24小时尿钾排泄量]与一份包含两个条目的水果和蔬菜消费问卷之间的关联。在对年龄、性别、维生素补充剂使用情况、吸烟状况和体重进行控制后，那些报告每日摄入≥5份水果和蔬菜的人，其钾排泄量（差值为15.6[95%置信区间：6.2至25.0]mmol/24小时）、尿钾/肌酐比值（1.2[0.5至2.0]）和血浆维生素C（10.0[-0.9至20.8]μmol/L）均高于那些报告每日摄入≤2.5份的人。β-胡萝卜素（p = 0.04）、维生素C（p = 0.01）和钾排泄量（p < 0.001）与水果摄入量相关，而非蔬菜摄入量。这份包含两个条目的问卷具有较高的特异性；超过3/4报告低摄入量的参与者其生物标志物也低于分布的上三分之一。
对于那些每天食用少于五份水果和蔬菜的人，通过简单问卷进行的水果和蔬菜摄入量自我报告得到了生物标志物的证实。尽管该工具在检测蔬菜份数方面有待改进，但它可能被证明对在初级保健中监测饮食预防方法有用，而无需进行侵入性且昂贵的生化测量。
