Assessment of flavonoid and fatty acid intake by chemical analysis of biomarkers and the duplicate diets

Dietary intake is important to investigate the relationship between diet and the occurrence of disease. However, it is difficult to assess the intake of nutrients such as flavonoids, minor fatty acids and plant sterols because the data on these nutrients in food composition tables are insufficient or because the bioavailability of these nutrients differs between foods. The results of studies investigating the relationship of these nutrients to disease are inconsistent, perhaps because of errors in the methods used to assess nutrient intake. The aim of this thesis was to evaluate physically and chemically based methods of measuring the intake of flavonoids, fatty acids, sterols and energy.We found differences of up to 80 mg per day in the intake of flavonols and flavones in subjects eating a variety of diets. The ratio of the within- to the between-subject variation in the intake of flavonols and flavones was lower than one, indicating that it is possible to study the relationship between flavonoid intake and disease. The food frequency questionnaire used in this study was suitable for classifying subjects by their flavonol intakes.We also found that the bioavailability of the flavonol quercetin differs between the major dietary sources. The bioavailability of quercetin from red wine was 75% of that from onions and from tea 50% of that from onions. Therefore, flavonols from red wine can probably not explain the lower incidence of coronary heart disease in France compared to other western countries. Concentrations of quercetin in plasma can be used as biomarkers to distinguish between subjects with a low and with a high flavonol intake. This is possible because of a relatively small variation of plasma quercetin and a linear relationship between quercetin intake to its concentrations in plasma and excretions in urine.Chemical analysis of food composites is a suitable method to assess the intake of a large number of fatty acids and sterols for subsamples of populations. We found large differences in the amount of these nutrients in the diets of middle-aged men living in 16 cohorts in seven countries. Three-day records are not suitable to measure individual energy intake, but they can be used to classify subjects by their energy intakes.In conclusion, the most feasible method to assess flavonol intake in epidemiological studies appears to be a food frequency questionnaire specially devised to assess flavonol intake and validated in a sub-population by biomarkers of flavonol intake. In addition, chemical analysis of food composites is a good tool to assess specific fatty acids and sterols in the diet of a population. Finally, when using 3-day food records, even from a motivated, lean, well-educated population, underestimation of intakes has to be taken into account

Overview of methods used to evaluate the adequacy of nutrient intakes for individuals and populations

The objective of the present paper is to review the methods of measuring micronutrient intake adequacy for individuals and for populations in order to ascertain best practice. A systematic review was conducted to locate studies on the methodological aspects of measuring nutrient adequacy. The results showed that for individuals, qualitative methods (to find probability of adequacy) and quantitative methods (to find confidence of adequacy) have been proposed for micronutrients where there is enough data to set an average nutrient requirement (ANR). If micronutrients do not have ANR, an adequate intake (AI) is often defined and can be used to assess adequacy, provided the distribution of daily intake over a number of days is known. The probability of an individual's intake being excessive can also be compared with the upper level of safe intake and the confidence of this estimate determined in a similar way. At the population level, adequacy can be judged from the ANR using the probability approach or its short cut – the estimated average requirement cut-point method. If the micronutrient does not have an ANR, adequacy cannot be determined from the average intake and must be expressed differently. The upper level of safe intake can be used for populations in a similar way to that of individuals. All of the methodological studies reviewed were from the American continent and all used the methodology described in the Institute of Medicine publications. The present methodology should now be adapted for use in Europe

Diet quality indices for research in low- and middle-income countries: a systematic review

Nutrition insecurity among urban poor in modernizing Asian metropolises is a critical issue. It is well recognized that in urban Asia the poor are food insecure. Across Asia the food retail environment is transforming rapidly, in which supermarkets increasingly replace traditional food vending, like markets and street vendors that the urban poor depend upon. The question is, how these transformations impact the diets of the urban poor? What drives their food choice? What are their daily shopping practices and how does that affect their dietary intake? To investigate this, we developed a cross-disciplinary nutrition and social practices study with a sequential quantitative-qualitative mixed-method design. Building on empirical evidence from Hanoi, Vietnam, the study links (i) food choice and measured dietary intake, with (ii) food retail environment, through (iii) food shopping practices and preferences of 400 women of reproductive age within the context of (iv) their transformative urban lifestyles. Methods included are a retail census with GPS coordinates to map the food retail environment, a household survey, a 24-h diet recall, multi-generation household interviews and shopping trips. We demonstrate that integrated sociological and nutritional perspectives are productive in rapidly generating evidence to comprehend the complex trade-offs between food safety and nutrition in everyday food consumption practices. We describe and reflect on our theoretical mix of dietary intake and social practices research, and our holistic mixed method approach which besides combining quantitative and qualitative methods, also voices the urban poor first hand

The association of frailty and outcomes of geriatric assessment with acute radiation-induced toxicity in patients with head and neck cancer

BACKGROUND AND PURPOSE: Geriatric impairments and frailty are highly prevalent in patients with head and neck cancer (HNC). This study investigated the association of frailty and outcomes of geriatric assessment (GA) with radiation-induced toxicity (RIT) in patients undergoing (chemo)radiotherapy ((C)RT) for HNC. MATERIALS AND METHODS: Between October 2014 and April 2016, patients with HNC were prospectively included in OncoLifeS, an institutional data-biobank. Before treatment initiation, patients underwent GA and frailty screening (Groningen Frailty Indicator and Geriatric 8). The main outcome of this study was RIT (weight loss, mucositis, salivary gland inflammation, oral pain, sore throat, hoarseness, dry mouth, dysgeusia, dysphagia and general pain) according to the common terminology criteria of adverse events (CTCAE) version 4.0. Linear mixed models were performed, to analyse factors associated with increasing mean RIT over time during the treatment period. RESULTS: 160 patients were included. 114 (71.3%) were male and the mean age was 66.1 years. Age ≥ 65 (β = 0.03(95 %CI = 0.01;0.05), p = 0.01), regional RT (β = 0.05(95 %CI = 0.02;0.09), p = 0.004), and concurrent chemotherapy (β = 0.04(95 %CI = 0.02;0.07), p = 0.001), were independent factors associated with increasing toxicity during the 7-week treatment period, adjusted for relevant covariates. None of the single items of GA, as well as the frailty screening instruments, were associated with increasing RIT. CONCLUSION: In this study, frailty and GA were not associated with additional RIT during treatment. These results suggest that (C)RT is equally tolerated in frail and non-frail patients, with respect to acute RIT. RT could be a suitable alternative to surgery in selected frail patients