Sufficient I intake is important for the synthesis of thyroid hormones, which play an important role in normal growth and development. Our aim was to estimate habitual I intake for the Dutch population and the risk of inadequate or excessive intakes. Further, we aimed to provide an insight into the dietary sources of I and the association with socio-demographic factors. Data from the Dutch National Food Consumption Survey 2007–2010 (n 3819; 7–69 years), and from the Dutch food and supplement composition tables were used to estimate habitual I intake with a calculation model. Contribution of food groups to I intake were computed and multiple linear regression was used to examine associations of intakes with socio-demographic factors. A total of ≤2 % of the population had an intake below the estimated average requirement or above the upper level. The main sources of I were bread containing iodised salt (39 %), dairy products (14 %) and non-alcoholic drinks (6 %). I intake (natural sources only, excluding iodised salt and supplements) was positively associated with (parental) education, which could at least partly be attributed to a higher consumption of dairy products. Among children, the consumption of bread, often containing iodised bakery salt, was positively associated with parental education. The I intake of the Dutch population (7–69 years) seems adequate, although it has decreased since the period before 2008. With the current effort to reduce salt intake and changing dietary patterns (i.e. less bread, more organic foods) it is important to keep a close track on the I status, important sources and potential risk groups.

It has been suggested that vitamin D2 is not very prevalent in the human food chain. However, data from a number of recent intervention studies suggest that the majority of subjects had measurable serum 25-hydroxyvitamin D2 (25(OH)D2) concentrations. Serum 25(OH)D2, unlike 25(OH)D3, is not directly influenced by exposure of skin to sun and thus has dietary origins; however, quantifying dietary vitamin D2 is difficult due to the limitations of food composition data. Therefore, the present study aimed to characterise serum 25(OH)D2 concentrations in the participants of the National Adult Nutrition Survey (NANS) in Ireland, and to use these serum concentrations to estimate the intake of vitamin D2 using a mathematical modelling approach. Serum 25(OH)D2 concentration was measured by a liquid chromatography–tandem MS method, and information on diet as well as subject characteristics was obtained from the NANS. Of these participants, 78·7 % (n 884) had serum 25(OH)D2 concentrations above the limit of quantification, and the mean, maximum, 10th, 50th (median) and 90th percentile values of serum 25(OH)D2 concentrations were 3·69, 27·6, 1·71, 2·96 and 6·36 nmol/l, respectively. To approximate the intake of vitamin D2 from these serum 25(OH)D2 concentrations, we used recently published data on the relationship between vitamin D intake and the responses of serum 25(OH)D concentrations. The projected 5th to 95th percentile intakes of vitamin D2 for adults were in the range of 0·9–1·2 and 5–6 μg/d, respectively, and the median intake ranged from 1·7 to 2·3 μg/d. In conclusion, the present data demonstrate that 25(OH)D2 concentrations are present in the sera of adults from this nationally representative sample. Vitamin D2 may have an impact on nutritional adequacy at a population level and thus warrants further investigation.

Data are limited on how dietary sources of energy and nutrient intakes differ among ethnic groups in the USA. The objective of the present study was to characterise dietary sources of energy, total fat, saturated fat, protein, dietary fibre and added sugar for five ethnic groups. A validated quantitative FFQ was used to collect dietary data from 186 916 men and women aged 45–75 years who were living in Hawaii and Los Angeles between 1993 and 1996. Participants represented five ethnic groups: African-American; Japanese-American; Native Hawaiian; Latino; Caucasian. The top ten dietary sources of energy contributed 36·2–49·6 % to total energy consumption, with rice and bread contributing the most (11·4–27·8 %) across all ethnic–sex groups. Major dietary sources of total fat were chicken/turkey dishes and butter among most groups. Ice cream, ice milk or frozen yogurt contributed 4·6–6·2 % to saturated fat intake across all ethnic–sex groups, except Latino-Mexico women. Chicken/turkey and bread were among the top dietary sources of protein (13·9–19·4 %). The top two sources of dietary fibre were bread and cereals (18·1–22 %) among all groups, except Latino-Mexico men. Regular sodas contributed the most to added sugar consumption. The present study provides, for the first time, data on the major dietary sources of energy, fat, saturated fat, protein, fibre and added sugar for these five ethnic groups in the USA. Such data are valuable for identifying target foods for nutritional intervention programmes and directing public health strategies aimed at reducing dietary risk factors for chronic disease.

Plant-based diets contain a plethora of secondary metabolites that may impact on health and disease prevention. Much attention has been focused on the potential bioactivity and nutritional relevance of several classes of phytochemicals such as flavonoids, carotenoids, phyto-oestrogens and glucosinolates. Less attention has been paid to simple phenolic acids that are widely found in fruit, vegetables, herbs, spices and beverages. Daily intakes may exceed 100 mg. In addition, bacteria in the gut can perform reactions that transform more complex plant phenolics such as anthocyanins, procyanidins, flavanones, flavonols, tannins and isoflavones into simple phenolic metabolites. The colon is thus a rich source of potentially active phenolic acids that may impact both locally and systemically on gut health. Both the small and large intestine (colon) contain absorption sites for phenolic acids but low post-prandial concentrations in plasma indicate minimal absorption early in the gastrointestinal tract and/or rapid hepatic metabolism and excretion. Therefore, any bioactivity that contributes to gut health may predominantly occur in the colon. Several phenolic acids affect the expression and activity of enzymes involved in the production of inflammatory mediators of pathways thought to be important in the development of gut disorders including colon cancer. However, at present, we remain largely ignorant as to which of these compounds are beneficial to gut health. Until we can elucidate which pro-inflammatory and potentially carcinogenetic changes in gene expression can be moderated by simple phenolic acids, it is not possible to recommend specific plant-based foods rich in particular phenolics to optimise gut health.

The objectives of the present study are to describe the dietary sources of total fat and of saturated fatty acids (SFA) and to formulate food-based dietary guidelines for SFA in Belgian adolescents. A random sample of 13–18-year-old adolescents was drawn from secondary schools in the region of Ghent. A 7d estimated food record method was used to quantify nutrient and food intake. The average daily SFA intake is 4% above the recommended 10% of the total energy contribution. The most important contributors of SFA on food group level were ‘fats, oils and savoury sauces’, ‘meat and meat products’, ‘sugar, confectionery, sweet fillings and sauces’, ‘cheese’, ‘milk and milk products’ and ‘bread, rusk and breakfast rolls’. On food subgroup level ‘fresh meat’, ‘high-fat margarine’ and ‘high-fat cheese’ had the highest contribution to SFA intake in all adolescents. Adolescents with a low SFA intake (lowest tertile) were compared with adolescents with a high intake (highest tertile). In the lowest tertile the intake of total fat and MUFA was significantly lower than in the highest tertile, while the intake of total carbohydrates, mono- and disaccharides and complex carbohydrates was significantly higher. Overall, the high-fat cheese intake is significantly lower in the lowest tertile, while the fruit intake is higher. The present analysis shows that the nutritional profile of Belgian adolescents could be potentially improved by decreasing the portion sizes of fresh meat (in boys), high-fat margarine, high-fat cheese and reducing intake of commercially prepared baked goods and processed foods, including fast foods.