临床实践指南：加拿大女性营养共识（三）
前情提要
第二章 女性营养总论
概述
富含蔬菜、水果、全谷物、低脂或脱脂乳制品、海产品、豆类和坚果，酒精适量（对非妊娠和非哺乳期女性），红肉及加工肉类较少，含糖甜饮料和精制谷物少，这种平衡、多样化饮食能降低慢性疾病包括2型糖尿病、心血管疾病和癌症的风险。（II-2）
女性的健康，包括她们的营养状况，会受到社会-心理、经济或地理环境的不良影响，这些组成了她们的“饮食环境”。健康饮食的障碍可能包括个人因素（如体能、收入）、社会因素（如家庭环境、社会支持）、社区条件（如邻近杂货店）及相关的政策（如获得社会支持项目的资格）。处于营养状况较差高风险的女性可能受益于额外的饮食建议或有针对性的干预。（III）
精心计划的素食在整个生命周期中都是健康的，必须注意蛋白质的摄入。对于严格素食者（如纯素食者）要关注的其他营养素包括锌、铁、维生素B12和ω-3脂肪酸。（II-2）
推荐意见
强调在女性整个生命周期中良好营养的重要性，一切重点在于营养食物摄入量恰当以保持健康体重。（I-A）
对于女性饮食摄入的讨论应明确实用、易于理解、易于实施并能形成可持续的饮食行为习惯。（III-B）
强调在生命周期中保持健康体重的重要性。体重指数（体重[kg]/身高[m]²）和腰围（cm）提供了评估健康风险的一般思路，应作为身体评估的常规部分进行测定。（II-2A）这个建议不适用于青春期、饮食紊乱的女性和孕妇。
支持女性了解生命周期中应关注的具体营养素，包括钙、铁、叶酸、维生素B12和维生素D。确保女性了解富含这些营养素的食物，鼓励她们经常适量摄入。（III-A）
存在铁缺乏高风险女性（如肉类摄入少或不吃肉、社会经济地位低下、来自发展中国家的移民，土著、因纽特人（北美的爱斯基摩人）和混血儿女性，月经导致明显的失血，分娩）应通过检测血红蛋白和血清铁蛋白进行筛查。如果确定铁缺乏，应开始口服铁元素治疗并持续至少6个月，严重贫血女性需要更高剂量。铁应同维生素C来源食物一起摄入。（III-A）有导致铁缺乏潜在疾病或对治疗无应答的患者应进行进一步检查和治疗。
对没有维生素B12缺乏症状或危险因素的健康女性不推荐进行常规检测。有维生素B12缺乏危险因素的女性（如蛋奶素食/纯素食、年龄超过50岁、胃病如萎缩性胃炎或胃旁路手术，小肠疾病，经常使用二甲双胍、长期使用H2受体阻滞剂或质子泵抑制剂）考虑补充维生素B12。（III-A）
从饮食中不能摄入推荐量钙的女性可能从钙补充剂中受益。（II-2A）当建议女性选择钙补充剂，应确保补充剂提供的钙元素剂量适当，确保女性明白她需要在标签上特别看这个。最好多次小量摄入钙，因为其吸收与摄入量呈负相关。任何时候钙元素摄入都不要超过500～600mg。（II-2A）应谨慎避免从饮食和补充剂中一起摄入的钙超过上限（成年女性2500mg）。
推荐加拿大膳食维生素D摄入不足的所有女性使用维生素D补充剂（I-A），特别是由于蜗居在家皮肤合成减少、皮肤色素沉着较深或遮盖皮肤的女性。
通过检测血清25羟维生素D水平筛查维生素D缺乏对于一般人群没有必要，但对于高风险女性应进行，如有骨折史、吸收不良、肾病或使用影响维生素D或骨代谢药物治疗（如长期使用类固醇、抗惊厥药物治疗）的女性。（III-A）
在日常门诊中，告诉所有育龄妇女从食物（如深绿色、叶菜类蔬菜和豆类）和多种维生素补充剂摄取足够叶酸的好处。（I-A）
Chapter 2: General Female Nutrition
Summary Statements
A balanced and varied diet higher in vegetables, fruit, whole grains, low- or non-fat dairy, seafood, legumes, and nuts; moderate in alcohol (for non-pregnant and non-lactating women); lower in red and processed meats; and low in sugar-sweetened beverages and refined grains reduces the risk of chronic diseases including type 2 diabetes, cardiovascular disease, and cancer. (II-2)
Women's health, including their nutritional status, can be adversely affected by psycho-social, economic, or geographic circumstances which comprise their "food environment." Barriers to healthy eating may include individual factors (e.g., physical ability, income), social factors (e.g., family situation, social support), community factors (e.g., proximity to grocery stores), and relevant policies (e.g., eligibility for social support programs). Women at high risk for poor nutritional status may benefit from additional dietary counselling or targeted interventions. (III)
A carefully planned vegetarian diet is healthy throughout the lifecycle; careful attention to protein is required. Other nutrients of concern for strict vegetarians (e.g., vegans) include zinc, iron, vitamin B12, and omega-3 fatty acids. (II-2)
Recommendations
Emphasize the importance of sound nutrition throughout the female lifecycle, with an overall focus on women's intake of nutritious foods in appropriate amounts for maintaining a healthy weight. (I-A)
Discussions of dietary intake with women should identify practical, easy to understand, easy to implement, and sustainable dietary practices. (III-B)
Stress the importance of maintaining a healthy body weight throughout the lifecycle. Body mass index (weight in kg/height in metres²) and waist circumference (cm) provide a general idea of health risk and should be measured as a routine part of physical assessments. (II-2A) This recommendation does not apply to adolescents and women with eating disorders or women who are pregnant.
Support women in understanding specific nutrients of concern across the female lifecycle, which include calcium, iron, folate, vitamin B12, and vitamin D. Ensure that women are aware of foods rich in these nutrients, and encourage their regular consumption in appropriate amounts. (III-A)
Women who are at high risk for iron deficiency (e.g., low or no meat intake; low socioeconomic status; immigrants from developing countries; First Nations, Inuit, and Métis women; significant blood loss due to menstruation, child birth) should be screened by measuring hemoglobin and serum ferritin. If iron deficiency is identified, oral elemental iron therapy should be initiated and continued for at least 6 months; higher doses are required for women with severe anemia. Iron should be taken with a source of vitamin C. (III-A) Patients with an underlying condition that causes iron deficiency or who do not respond to treatment should be referred for further investigation and management.
Routine testing of healthy women without symptoms or risk factors for vitamin B12 deficiency is not recommended. Consider supplementary vitamin B12 for women with risk factors for deficiency (e.g., vegetarian/vegan diet, over age 50, gastric disorders such as atrophic gastritis or gastric bypass, small bowel disease, and regular use of metformin, chronic H2-blockers, or proton pump inhibitors). (III-A)
Women who are not able to consume the recommended dietary allowance of calcium in their diet may benefit from a calcium supplement. (II-2A) When counselling a woman in the selection of a calcium supplement, ensure that the supplement provides an adequate dose of "elemental calcium" and that the woman understands she needs to look specifically for this on the label. It is best to take multiple small doses of calcium as absorption is inversely related to intake; no more than 500 to 600 mg of elemental calcium at any one time. (II-2A) Caution should be used to avoid exceeding the upper limit for calcium from diet and supplements combined (2500 mg for adult women).
Recommend a vitamin D supplement to all Canadian women who consume insufficient dietary vitamin D (I-A), particularly those with decreased cutaneous synthesis due to being homebound, having darker skin pigmentation, or who cover their skin.
Screening for vitamin D deficiency by measuring serum 25(OH)D is not necessary for the general population but should be carried out in high risk women such as those with a history of fractures, malabsorption, renal disease, or using medications that impact vitamin D or bone metabolism (e.g., chronic steroid use, anticonvulsant therapy). (III-A)
During routine visits, advise all women of reproductive age about the benefits of adequate intake of folate from foods (e.g., dark green, leafy vegetables and legumes) and folic acid in a multivitamin supplement. (I-A)
翻译：肖慧娟（天津市第三中心医院营养科）
