金湖地区儿童及成人膳食铅摄入量检测

目的 了解江苏省金湖地区儿童、成人膳食铅的摄入量,并评价其安全性。方法 收集62名研究对象连续3 d的双份饭(duplicate portion)样本,使用石墨炉原子吸收光谱法测定铅含量。采用联合国粮农组织和世界卫生组织食品添加剂联合专家委员会推荐的暂定每周耐受摄入量(PTWI)评价江苏省金湖地区儿童、成人膳食铅摄入量的安全性。结果 共收集符合标准的双份饭样本178份,儿童、成人各89份,铅的检出率均为94.4%,江苏省金湖地区儿童及成人每天膳食铅摄入量的范围分别为0.1~7.4,0.1~7.6μg/(kg·bw);P97.5分别为6.9,5.3μg/(kg·bw);平均膳食铅摄入量分别为(2.2±1.7),(1.5±1.3)μg/(kg·bw);每周膳食铅摄入量的P97.5分别为24.3,23.6μg/(kg·bw),各占PTWI的97.2%,94.4%。儿童每周膳食铅摄入量高于成人,差异有统计学意义(P<0.01)。结论 江苏省金湖地区儿童、成人膳食铅污染状况较为严重,需采取有效措施降低铅的膳食摄入量以减轻铅暴露引起的不良健康反应。     

不同膳食摄入量研究方法比较

膳食摄入量研究是一种评估有害和营养物质对人类健康造成潜在影响的方法,是各国确保本国居民膳食安全和营养质量的重要措施之一。本文将简要介绍不同的膳食摄入量研究方法,并就不同研究方法进行比较,最后总结出不同的研究方法的优缺点。     

2000年中国总膳食研究——膳食汞摄入量

目的了解2000年中国不同地区膳食中总汞含量和成年男子人均汞膳食摄入量。方法采用总膳食研究方法,通过膳食调查、统计不同地区人群各种食物的消费量、按照所得的食物消费量数据烹调加工成可食的各种食物类别。膳食样品中总汞含量采用冷原子吸收光谱法测定,并按成年男子各种食品的消费量与实测膳食中汞的含量相乘得到不同地区总汞的实际摄入量。采用世界卫生组织推荐的总汞每周可耐受摄入量(PTWI)值评价中国四个大区成年男子膳食中总汞摄入的安全性。结果除某些地区的个别食物样品超过中国食品卫生中总汞限量标准外,四个大区和全国成年男子平均膳食总汞摄入量(占%PTWI)分别为:8·86μg(19·7%)、4·69μg(10·4%)、7·01μg(15·6%)、6·88μg(15·3%)和6·86μg(15·2%)。结论结果显示中国人群膳食中总汞摄入量是安全的。     

镇江市某大学学生膳食汞摄入量调查

目的了解镇江市大学生膳食汞摄入量水平,并评价其安全性。方法在镇江市某大学随机选择24名大学生作为研究对象,用双份饭法收集其连续3d(包含一个周末)的全部食物(包括饮水、饮料、零食等),利用冷原子吸收光谱法(直接汞测定仪)测定膳食样品中总汞含量,根据联合国粮农组织和世界卫生组织(FAO/WHO)食品添加剂联合专家委员会(JECFA)推荐的总汞暂定每周可耐受摄入量(PTWI)值(5μg/kg BW),评价大学生膳食中总汞摄入的安全性。结果被调查大学生膳食总汞平均摄入量为1.68μg/d,平均每天膳食汞的摄入量为0.031 7μg/kg BW,每周膳食汞的摄入量为0.22μg/kg BW,远低于PTWI。结论该校大学生调查期间膳食总汞摄入量未超过PTWI,处于安全水平。     

膳食叶酸参考摄入量研究进展

叶酸是一种水溶性维生素,作为一碳单位的载体,参与核苷酸合成、DNA甲基化反应,对于人体细胞生长、分化、修复至关重要,并具有预防神经管缺陷的作用。随着对于叶酸与出生缺陷、心血管疾病、肿瘤以及神经退行性疾病的关系的研究逐步深入,叶酸已成为一种备受关注的微量营养素。叶酸缺乏可导致成人和儿童巨幼红细胞贫血,增加孕妇发生先兆子痫、胎盘早剥、贫血的风险,可导致孕妇自发性流产。孕早期叶酸缺乏可引起胎儿神经管缺陷。中国从2010年开始向育龄妇女推荐叶酸补充剂,以预防神经管缺陷。本文针对叶酸膳食参考摄入量的制定及研究进展进行梳理回顾,旨在为中国居民膳食营养素参考摄入量叶酸的修订提供参考。[营养学报,2023,45(4):326-330]     

锌的膳食参考摄入量研究进展

锌是人体必需微量元素,近年来膳食锌及锌补充剂与健康的关系备受关注。虽然我国人群锌营养状况显著改善,但各年龄段仍存在不同程度的缺锌。本文在我国研究数据的基础上,探讨了锌吸收率、锌营养状况评价、母乳锌水平以及可耐受最高摄入量等方面的研究进展,并比较了其他国家锌的推荐摄入量,为2023版锌膳食参考摄入量修订提供借鉴和参考依据。     

现有维生素D的膳食参考摄入量急需提高

维生素D补充可能在降低许多慢性疾病风险中发挥作用。为了快速、显著降低维生素D不足引起疾病的发生率,通过维生素D强化食品或维生素D补充剂增加其摄入量是一个简单、低成本的方法,但目前可耐受最高摄人量和推荐摄入量已经过时。笔者敦促有关方面,作为高度优先事项重新评估维生索D的膳食参考摄入量。     

2000年中国总膳食研究—膳食砷摄入量

目的了解和评价2000年中国不同地区膳食中总砷及无机砷的含量和成年男子人均膳食摄入量。方法采用总膳食研究方法,通过膳食调查、统计不同地区人群各种食物的消费量、按照所得的食物消费量数据烹调加工并混合成可食的各种食物类别。膳食样品中总砷含量采用氢化物发生原子吸收光谱法,无机砷含量采用氢化物发生原子荧光法测定,并按成年男子各种食品的消费量与实测膳食中砷的含量相乘得到不同地区总砷及无机砷的实际摄入量。采用世界卫生组织推荐的无机砷每周可耐受摄入量(PTWI)值评价我国4个大区成年男子膳食中无机砷摄入的安全性。结果某些地区的个别食物样品超过我国的食品卫生中砷的限量标准。我国4个大区(北方一区,北方二区,南方一区,南方二区)和中国标准人膳食中总砷和无机砷摄入量(占PTWI百分率)分别为:0.220mg,0.094mg(69.3%);0.254mg,0.098mg(72.2%);0.296mg,0.048mg(35.6%);0.335mg,0.077mg(57.3%)和0.276mg,0.079mg(58.6%)。结论本研究首次运用总膳食的方法得到我国4个大区成年男子和中国标准人膳食中总砷及无机砷摄入量数据。结果显示我国人群膳食中总砷及无机砷摄入量是安全的。     

铁可耐受最高摄入量制定的研究进展

过量摄入铁会对人体产生多种危害,许多国家因此制定了铁的可耐受最高摄入量(UL)以指导国民对该营养素安全摄入。本文回顾了各国铁的UL制定或修订的历史,介绍了铁的UL的制定方法和依据,并对各国在铁UL的制定方法上的异同加以分析。通过上述回顾和分析,本文提出了在铁的UL制定过程中仍需解决的一些问题,对今后的研究重点进行了探讨。     

营口地区膳食中邻苯二甲酸酯摄入量的调查

目的:调查评估本地居民膳食中邻苯二甲酸酯类化合物摄入量水平。方法:根据世界卫生组织推荐的监测和评价人群膳食化学污染物摄入量的总膳食研究方法,参考US EPA 8061A方法检测。结果:测试了本地区膳食食品样品20份及食品塑料包装袋20份、塑料餐盒10份,检出DEHP、DBP和DEP,浓度在0.26～1.19mg/kg之间。结论:本地区食品膳食中存在PAEs的污染,尤其是以DBP和DE-HP的含量最高,PAEs总摄入量平均值为0.12mg/kg,高于OEHHA的建议值0.05mg/kg。     

Dietary intake of lead by children and adults from Germany measured by the duplicate method

The dietary lead intake was studied among children and adults from Germany. Two different age groups of children (A: 1.8, 1.3 – 3.0 years, B: 3.8, 1.8 – 5.2 years) and one group of adults (D: 40.9, 24 – 64 years) were from the highly industrialized Ruhr district and one group of children from the North Sea island Amrum (C: 3.9, 1.5 – 5.3 years). A total of 229 duplicate food portions were collected from 49 individuals between December 1994 and May 1995. Sampling period for each participant was either 3 (groups B and D) or 7 days (groups A and C). Lead levels in duplicate samples were measured by electrothermal atomic absorption spectrometry. The lead intakes (median, range) for the different groups were as follows: Group A: 0.21 (0.05 – 1.5) μg/(kg _bwday), group B: 0.68 (0.06 – 1.6) μg/(kg _bwday), group C: 0.29 (0.04 – 1.6) μg/(kg _bwday) and group D: 0.26 (0.07 – 0.83) μg/(kg _bwday). No value exceeded the provisional tolerable weekly intake (PTWI) of 25 μg/(kg _bwweek) proposed by the WHO. The median and maximum of the different groups amounted to 7.2 – 16% and 16 – 36% of the PTWI, respectively. It is concluded that health risks due to dietary lead intake seem to be low in Germany.     

Dietary intake of persistent organic pollutants (POPs) by German children using duplicate portion sampling

The dietary intake of persistent organic pollutants (POPs) was studied in 14 German children at the age of 1.5 to 5.3 years from the North Sea island Amrum. A total of 98 duplicate samples were collected between April and May 1995. The sampling period for each participant was 7 days. Concentrations of POPs were measured by capillary gas chromatography and electron capture detection. The median daily intake [ng/(kgbw.day)] for the different compounds were as follows: 1.9 for alpha-HCH, 1.2 for beta-HCH, 9.5 for gamma-HCH, 4.6 for HCB, 3.4 for DDT, 11.2 for DDE, 1.1 for PCB 101, 5.1 for, PCB 138, 5.2 for PCB 153 and 2.2 for PCB 180. Compared to acceptable or tolerable daily intake (ADI/TDI) proposed by WHO and other organizations the dietary intake of POPs was low. The median values of the ADI/TDI for the POPs was less than 2.2%. The highest percentage of tolerable intake was found for the sum of PCB and amounted to 20.4%. However, compared with minimal risk levels (ATSDR), the percentage of dietary intake was much higher, especially for gamma-HCH (based on median intake: 95%), for HCB (23.1%) and for PCB (69%).     

Nutritional covariates of dietary calcium in elderly Japanese women: results of a study using the duplicate portion sampling method

OBJECTIVES: The purposes of this study were to determine the intake of nutrients related to bone health, including calcium (Ca), phosphorus (P), sodium (Na), potassium (K), protein, and vitamin D, in elderly Japanese women and to examine possible intercorrelations between Ca intake and other nutrients. METHODS: Fifty-three elderly women in a rural community in Japan participated by supplying duplicate meal samples of everything they ate during a 24-h period. Dietary Ca, P, Na, K, protein, and vitamin D intakes were examined. The mean (standard deviation) age of the 53 women was 68.2 y (6.4 y). RESULTS: The mean (standard deviation) intakes of dietary Ca, P, Na, K, protein, and vitamin D were 670 (219) mg/d, 1019 (267) mg/d, 4203 (1341) mg/d, 2752 (844) mg/d, 65.2 (18.3) g/d, and 9.90 (8,89) microg/d, respectively. Dietary Ca was significantly correlated with dietary P (r = 0.732, P < 0.0001), Na (r = 0.336, P = 0.0140), K (r = 0.571, P < 0.0001), and protein (r = 0.563, P < 0.0001), but not with vitamin D. After adjusting the data to reflect the total dry weight, dietary Ca was still correlated with P (r = 0.696, P < 0.0001), K (r = 0.423, P = 0.0018), and protein (r = 0.405, P = 0.0029). CONCLUSIONS: The intake of dietary nutrients relevant to bone health in ambulatory Japanese elderly women was examined and documented. The potential confounding effects of these nutrients, especially P, K, and protein, should be taken into account when evaluating the effects of dietary Ca on bone health in observational studies.     

Dietary intake of lead, cadmium, copper and zinc by children from the German North Sea island Amrum

The dietary intake of metals was studied in seven male and seven female children at the age of 1.5 to 5.3 years living in a remote area of Germany, the North Sea island Amrum. The dietary intake of lead and cadmium was measured by a seven-day-duplicate study using atomic absorption spectrometry. The dietary intake of copper and zinc were calculated from food diaries. The median lead and cadmium intakes were 2.1 micrograms/(kgbw x week) [range: 0.63-5.1 micrograms/(kgbw x week)] and 2.7 micrograms/(kgbw x week) [range: 1.7-4.4 micrograms/(kgbw x week)]. The median daily intake of copper and zinc were 1.1 mg/d (range: 0.54-2.5 mg/d) and 5.7 mg/d (range: 2.7-14 mg/d). Compared to the provisional tolerable weekly intake (PTWI) of 25 micrograms/(kgbw x week) proposed by the WHO the dietary intake of lead was low. The median amounted to 8.5% and the maximum to 20% of the PTWI. The cadmium intake was comparatively high. The median amounted to 39% and the maximum to 63% of the PTWI [7 micrograms/(kgbw x week)]. The median intake of copper was in the range of the values recommended by the German Society of Nutrition (0.7-1.0 mg/d and 1.0-1.5 mg/d for children at the age of 1-< 4 years and 4-< 7 years). Twenty-three percent of the calculated intakes were below these values. The median intake of zinc however did not reach the recommended dietary intake of 7 and 10 mg/d for children at the age of 1-< 4 years and 4-< 7 years.     

A study of the use of a photographic food atlas to estimate served and self-served portion sizes

Background: Although it is generally accepted that a weighed intake is the most valid way of assessing nutrient intake, this is not always the most appropriate method. Photographs have been suggested as a useful aid in assessing portion size when other methods of recording dietary intake are used. Method: Male and female subjects ( n =100) were recruited to assess portion sizes of served amounts of mashed potato or cornflakes using food photographs. A second group of subjects ( n =40) were recruited to assess portion sizes of self-served mashed potato or cornflakes using the same photographs. Results: Estimates varied from −70.6% underestimation to +198.7% overestimation for mashed potato, with less variation for the cornflakes where portions were served.® Where the food was self-served, results ranged from −38% and −64% underestimation to +61% and +88% overestimation for cornflakes and mashed potato, respectively.Correlation coefficients between estimated and actual weights of food showed them to be of statistical significance ( P <0.05). Conclusion: Food photographs are a useful and convenient aid in the estimation of food portion sizes.     

Human exposure in Italy to lead,cadmium and mercury through fish and seafood product consumption from Eastern Central Atlantic Fishing Area

The presence of cadmium (Cd), lead (Pb) and mercury (Hg) was investigated in fish and seafood products collected from the FAO Major Fishing Area 34, Eastern Central Atlantic. Samples were purchased from different retail outlets in Italy. Samples were selected so as to assess human exposure through diet. Metals were detected by Q-ICP-MS and Hg-AAS. All the metal concentrations detected were largely below the maximum levels (MLs) established by the European Union. The exposure assessment was undertaken by matching the concentration of Cd, Pb and total Hg in fish and other seafood products selected purposed according to Italian consumption data. The estimated weekly intakes (EWIs) for the evaluated elements related to the consumption of fish and other seafood products by the median of the Italian total population accounted for 14%, 2% and 14% of the standard tolerable weekly intake (TWI) for Cd and Hg as well as the provisional tolerable weekly intake (PTWI) for Pb, respectively.