Simple methods to obtain food listing and portion size distribution estimates for use in semi-quantitative dietary assessment methods

Reliability and validity of a semi-quantitative food frequency questionnaire: dietary intake assessment among multi-ethnic populations in Northwest China

BACKGROUND

Few multi-ethnic dietary culture-sensitive food frequency questionnaires (FFQ) have been developed due to the complexity and diversity of cooking methods and styles. This study aimed to develop and validate a specific FFQ among multi-ethnic groups in Northwest China.

METHODS

In the reliability study, 139 participants aged 20-65 completed two identical FFQs separated by 3 months. The relative validation of the FFQ was assessed by three 24-h recalls (24HR) employed in the interval of two FFQs, as a reference. Stratified analyses were also conducted by the major ethnic groups (Han nationality or Ethnic minority).

RESULTS

For reproducibility, the median (range) of Spearman's correlation coefficients (SCC) was 0.71 (0.43-0.84) for nutrients. The intra-class correlation coefficients (ICC) covered a spectrum from 0.39 to 0.78 (median: 0.64). Meanwhile, the weighted kappa values ranged from 0.11 to 0.64. For validity, the median (range) of Pearson's correlation coefficients derived from the energy unadjusted and the adjusted values between FFQ and 24HR were 0.61 (0.12-0.79) and 0.56 (0.12-0.77), respectively. The results of correlation coefficients were similar between the two ethnic groups. Moreover, the Bland-Altman plots likewise demonstrated a satisfactory level of agreement between the two methods.

CONCLUSIONS

The FFQ showed acceptable reproducibility and moderate relative validity for evaluating dietary intake among multi-ethnic groups in northwest China. It could be a credible nutritional screening tool for forthcoming epidemiological surveys of these populations.

Front-of-pack labels: "Directive" versus "informative" approaches

Front-of-pack labels (FOPLs) aim at communicating to consumers the health value of food items in support of public health policies. Two main types can be discerned: directive and semidirective FOPLs using color schemes (e.g., Nutri-Score) and informative FOPLs (e.g., Nutrinform Battery). Directive approaches tend to show a "wear-out effect" and, additionally, they tend to have various underlying conceptual problems. Usually, their nutritional scores are calculated using changing, arbitrary algorithms and involve a reductionist set of parameters of debatable validity. Thus, they overstate the effects of selected nutritional factors, such as saturated fat and energy, while overlooking the food matrix and the more holistic aspects of nourishment. Moreover, they do not reflect the portion that is consumed, ignore the preparation steps at home, and fail to serve as a useful basis for composing a healthy diet. Also, so long as the nutritional formulations match the algorithmic standards, they tend to allow ultra-processed products. Thus, this might confuse and mislead consumers. Overconfidence in green-colored labels could even result in unbalanced dietary choices, whereas avoidance of red products may eliminate certain foods from the diet that are rich in essential nutrients (e.g., cheese), leading to opposite results than aimed for. The latter is particularly relevant to vulnerable populations, such as the young, pregnant women, and older adults, or for individuals with specific needs. Taken together, directive FOPLs such as Nutri-Score contradict the declared intent of the European Commission to empower consumers to undertake healthy and balanced diets based on easily accessible and robust information. Although informative systems usually also keep the focus on a few selected nutritional parameters, they have are less paternalizing and obviate the need to classify foods as healthy or unhealthy. They also focus attention on the individual portions that are consumed (even if the definition of portion size remains contentious). Given the importance of dietary patterns, rather than individual foods or nutrients, directiveFOPLs of the Nutri-Score type represent a regretful case of nutritionism. Finally, attempts to associate the adoption of a FOPL with an improvement in the health status are few and mainly applied in virtual settings; none of which are longitudinal, nor have they been able to identify a causal link.

Valuing the Diversity of Research Methods to Advance Nutrition Science

The ASN Board of Directors appointed the Nutrition Research Task Force to develop a report on scientific methods used in nutrition science to advance discovery, interpretation, and application of knowledge in the field. The genesis of this report was growing concern about the tone of discourse among nutrition professionals and the implications of acrimony on the productive study and translation of nutrition science. Too often, honest differences of opinion are cast as conflicts instead of areas of needed collaboration. Recognition of the value (and limitations) of contributions from well-executed nutrition science derived from the various approaches used in the discipline, as well as appreciation of how their layering will yield the strongest evidence base, will provide a basis for greater productivity and impact. Greater collaborative efforts within the field of nutrition science will require an understanding that each method or approach has a place and function that should be valued and used together to create the nutrition evidence base. Precision nutrition was identified as an important emerging nutrition topic by the preponderance of task force members, and this theme was adopted for the report because it lent itself to integration of many approaches in nutrition science. Although the primary audience for this report is nutrition researchers and other nutrition professionals, a secondary aim is to develop a document useful for the various audiences that translate nutrition research, including journalists, clinicians, and policymakers. The intent is to promote accurate, transparent, verifiable evidence-based communication about nutrition science. This will facilitate reasoned interpretation and application of emerging findings and, thereby, improve understanding and trust in nutrition science and appropriate characterization, development, and adoption of recommendations.

Validity and reliability of a simplified food frequency questionnaire: a cross sectional study among physical health examination adults in southwest region of China

Background

In China, many people are regarded suitable for participating in regular physical examination for diagnosis and prevention of diseases. Some simplified food frequency questionnaires have been designed and used; however, the accuracy of the questionnaire is absent. This study aimed to examine the reliability and validity of simplified food frequency questionnaire (SFFQ) used among adults undergoing physical examination in southwest region of China.

Methods

This was a cross-sectional study conducted among physical health examination adults in the Southwest region of China. A total of 239 participants aged 20–65 were included from February 2019 to June 2019. The performance of SFFQ was evaluated by means of a three-day 24-h dietary record (3R24). The relative validity and agreement was assessed by Pearson’s correlation and intra-class correlation coefficients (ICC), respectively.

Results

The median energy-adjusted ICC of food groups between SFFQ2 and SFFQ1 was 0.59 (range: 0.49–0.73) and the ICC of nutrients was 0.47(range: 0.39–0.76). The Pearson correlation showed a valid comparisons between SFFQ1 and 3R24, ranging from -0.086 to 0.93 for food and 0.21 to 0.71 for nutrition, respectively. The energy-adjustment slightly increased the correlation coefficients.

Conclusions

The reliability and validity of SFFQ was acceptable, and it could be an appropriate dietary assessment tool for the future epidemiological studies conducted among physical health examination adults of southwest China.

Trial registration

CHiCTR, ChiCTR1900020934, Registered 22 January 2019, https://www.chictr.org.cn/edit.aspx?pid=35414&htm=4.

Dietary patterns of Chinese women of childbearing age during pregnancy and their relationship to the neonatal birth weight

OBJECTIVE

To examine the type of maternal dietary patterns during pregnancy and the distribution characteristics of children's birth weight and the association between dietary patterns and neonatal birth weight in China.

METHODS

Data were derived from a cross-sectional program named "The prevalence and risk factors of birth defects in Shaanxi Province" in July to November in 2013. A stratified multistage random sampling method was used to select women and their children. The mother's diet during pregnancy was investigated using semi-quantitative food frequency questionnaire (FFQ) to collect the frequency and amount of food consumption, and the newborn birth weight as well as related social demographic information was collected at the same time. In our study, 0-1 year old children and their mothers with complete dietary survey data were selected as research objects. The main dietary patterns were identified according to factor analysis, and latent class analysis (LCA) was used to investigate the social demographic factors affecting dietary patterns. The logistic regression model was used to assess the association between birth weight and maternal dietary patterns during pregnancy by establishing three adjusting models and the data were stratified for further analysis by urban-rural and regions.

RESULTS

A total of 15,980 participants were involved in this study. Four dietary patterns were identified: "vegetarian pattern", "balance pattern", "traditional pattern" and "processing pattern". Compared with moderate tertile, women in the highest tertile of adherence to vegetarian pattern increased the risk of low birth weight in offspring in rural areas (OR = 1.61, 95%CI:1.06-2.93) and middle region (OR = 1.75, 95%CI:1.18-2.62), and the traditional pattern had greater odds of lower birth weight in the middle region (OR = 1.55, 95%CI:1.05-3.75). The processing pattern was found a protective factor for the occurrence of low birth weight in rural areas (OR = 0.98, 95%CI:0.43-0.99) but was a risk factor for low birth weight in the southern region (OR = 8.83, 95%CI:1.22-15.16). The balance pattern was a protective factor for the occurrence of low birth weight in the northern region(OR = 0.35, 95%CI:0.14-0.83).

CONCLUSION

The vegetarian and traditional pattern may be positively related to a higher risk of low birth weight while the balanced pattern may keep birth weight of offspring within the appropriate range. Health education of balanced diet and individual nutrition guidance during pregnancy should be strengthened, to make the dietary structure during pregnancy are more reasonable, reduce the occurrence of adverse birth weight of newborns.