Antioxidant intake has been associated with less progression of radiographic knee osteoarthritis (OA), but studies of carotenoid biomarkers and OA have not been done. We examined associations between serum concentrations of nine naturally occurring carotenoids and radiographic knee OA.

The study design was matched case–control. Sera were analysed by high-performance liquid chromatography for nine carotenoids: lutein, zeaxanthin, α- and β-cryptoxanthin, trans- and cis-lycopene, α-carotene, and trans- and cis-β-carotene. Conditional logistic regression was used to estimate the association between tertiles of each carotenoid and radiographic knee OA, independent of body mass index, education, serum cholesterol, and the other carotenoids.

Johnston County, North Carolina, United States of America.

Two-hundred cases with radiographic knee OA (Kellgren–Lawrence grades ≥2) and 200 controls (Kellgren–Lawrence grade = 0) were randomly selected from the Johnston County Osteoarthritis Project, and were matched on age, gender and race.

Participants with serum levels of lutein or β-cryptoxanthin in the highest tertile were approximately 70% less likely to have knee OA than controls {odds ratio (OR) [95% confidence interval (CI)] = 0.28 [0.11, 0.73] and 0.36 [0.14, 0.95], respectively}. Those in the highest tertile of trans-β-carotene (OR = 6.40 [1.86, 22.1]) and zeaxanthin (OR = 3.06 [1.19, 7.85]) were more likely to have knee OA.

While certain carotenoids may protect against knee OA, others may increase the odds of knee OA. Further study of carotenoids and knee OA are warranted before clinical recommendations about these substances and knee OA can be made.

In a sample of older Japanese American women, we aimed to: (1) describe the most commonly consumed soy foods, (2) estimate dietary soy isoflavone intake, (3) describe characteristics associated with dietary soy isoflavone intake, and (4) compare our estimates with previously published estimates in other Japanese samples.

A 14-item soy food-frequency questionnaire was administered to older Japanese American women and responses were converted to quantitative estimates of soy isoflavones (genistein plus daidzein). Multiple regression was used to examine characteristics associated with dietary soy isoflavone intake, including self-reported lifestyle and cultural factors and dietary intake of various foods ascertained from a semi-quantitative food-frequency questionnaire. To compare our estimates with other samples, a review of the literature was conducted.

Data are from 274 women aged 65+ years, recruited from a longitudinal cohort study of Japanese Americans in King County, Washington State.

The soy foods most commonly consumed were tofu (soybean curd), miso (fermented soybean paste) and aburaage (fried thin soybean curd). The mean intake of dietary soy isoflavones was 10.2 (standard deviation (SD), 12.4) mg day−1, approximately a quarter to a half that of previously published estimates in Japanese samples. Dietary soy isoflavone intake was positively associated with speaking Japanese, the consumption of traditional Japanese dishes (kamaboko, manju and mochi), low-fat/non-fat milk and yellow/red vegetables, vitamin E supplement use, and walking several blocks each day. Dietary soy isoflavone intake was negatively associated with the consumption of butter.

The estimated dietary soy isoflavone intake in Japanese American women living in King County, Washington State was about a quarter to a half that of women living in Japan. Dietary soy isoflavone intake was associated with speaking Japanese and healthy lifestyle and dietary habits.

To describe scales that measure motivations for changing dietary behaviour, and to examine associations of these scales with current diet and dietary change.

A secondary analysis of a randomised trial of a self-help intervention to promote lower fat and higher fruit and vegetable consumption.

Participants and setting: Participants were 1205 adults selected at random from enrolees of a large Health Maintenance Organization. At baseline, data were collected on motives for changing diet, fruit and vegetable intake, fat-related dietary habits, and demographic characteristics. Participants were then randomised to receive the intervention or to receive no materials. A follow-up survey was administered at 12 months.

A majority of participants reported that it was very important to make dietary changes to feel better (72%) and to control an existing medical problem (57%), but very few (4%) were motivated by pressure from others. Factor analysis of the diet motivation items yielded two intrinsic (‘self-image’ and ‘personal health’) and one extrinsic (‘social pressure’) scales with fair internal consistency reliabilities (Cronbach's α = 0.59 to 0.68). Motivation scales were statistically significantly associated with demographic characteristics and baseline diet. For example, desire for a better self-image was a stronger motivator for changing diet among females, while personal health was more important to older persons and men (P < 0.001). Social pressure to change diet was statistically significantly associated with higher fat intake (r = 0.11) and self-image was associated with lower fat intake (r = −0.14, both P < 0.001). Motivation by social pressure and self-image were both significantly associated with greater fat reduction at 12 months post-intervention (P < 0.05).

The intrinsic and extrinsic motivation scales were weakly associated with current diet and predicted response to dietary intervention. More research is needed to better characterise and measure motives for dietary change, and to test whether tailoring interventions based on individuals' motives for dietary change would improve intervention effectiveness.

To evaluate the 137-item Utah Picture-sort Food-frequency Questionnaire (FFQ) in the measurement of usual dietary intake in older adults.

The picture-sort FFQ was administered at baseline and again one year later. Three seasonal 24-hour dietary recall interviews were collected during the year between the two FFQs. Mean nutrient intakes were compared between methods and between administrations of the FFQ.

The FFQ interviews were administered in respondents' homes or care-centres. The 24-hour diet recalls were conducted by telephone interview on random days of the week.

Two-hundred-and-eight men and women aged 55–84 years were recruited by random sample of controls from a case–control study of nutrition and bone health in Utah.

After adjustment for total energy intake, median Spearman rank correlation coefficients between the two picture-sort FFQs were 0.69 for men aged ≤69 years, 0.66 for men aged >69 years; and 0.68 for women aged ≤69 years, 0.67 for women aged >69 years. Median correlation coefficients between methods were 0.50 for men ≤69 years old, 0.52 for men >69 years old; 0.55 for women ≤69 years old, 0.46 for women >69 years old.

We report intake correlations between methods and administrations comparable to those reported in the literature for traditional paper-and-pencil FFQs and one other picture-sort method of FFQ. This dietary assessment method may improve ease and accuracy of response in this and other populations with low literacy levels, poor memory skill, impaired hearing, or poor vision.

An interviewer-administered quantitative food-frequency questionnaire (FFQ) was developed to determine the energy and nutrient intakes of adult Jamaicans of African origin as part of a study of the epidemiology of diabetes and hypertension.

Reproducibility of the questionnaire was investigated in 123 participants aged 25–74 years. The relative validity of the FFQ was assessed against twelve 24-hour recalls administered over 12 months in 73 of the participants. In addition, energy intakes (EI) were compared with estimated basal metabolic rates (BMR).

Reproducibility correlation coefficients (Pearson and intraclass) varied between 0.42 for retinol and 0.71 for carbohydrate, with most values falling between 0.50 and 0.60. When compared with repeated 24-hour recalls, the FFQ estimated slightly higher energy (mean 6%) and macronutrient intakes (mean 2–14%), and was within 5% when expressed as a percentage of energy intake. Micronutrients were higher by 1.19 (calcium) to 1.61 times (vitamin C). Unadjusted correlations between the FFQ and the reference method ranged from 0.20 for beta-carotene to 0.86 for alcohol. Cross-classification of nutrients into quartiles showed that 46–48% of participants in the lowest and highest quartiles were jointly classified by both methods. Misclassifications were low for most nutrients with one or two persons misclassified at the extreme quartiles. EI/BMR ratios suggested light to moderate activity levels appropriate for an urban population in a developing country.

The FFQ showed reasonable reproducibility and validity and is suitable for estimating the habitual intakes of energy and macronutrients, but was poor for some micronutrients (retinol and beta-carotene).

To estimate mercury intake due to fish consumption among the individuals from Gipuzkoa participating in the European Prospective Investigation into Cancer (EPIC), and to validate the estimation of mercury exposure through diet, by measuring blood mercury level.

The population for the EPIC Gipuzkoa cohort was recruited from 1992 to 1995. Each individual's diet was assessed regarding habitual intake over the previous year, using the diet history method. Blood samples were taken at the time of the interview. The mercury content of the fish species consumed was supplied by the Food Chemical Surveillance Programme in the Basque Country.

For the estimation, 8417 volunteers, men and women, aged 35–65 years, of the EPIC cohort; for the validation, a random sample of 120 individuals stratified by fish intake was taken.

The validation study confirmed the relationship between fish consumption and mercury intake, as well as between fish consumption and mercury in erythrocytes. 99.9% of individuals have intakes below 75% of the Provisional Tolerable Weekly Intake (PTWI) of mercury established by the World Health Organization. But the limit dosage recommended by the United States Environmental Protection Agency, measured by the average risk index, would be exceeded often.

No individual from the cohort would exceed the PTWI of mercury. Nevertheless, owing to the amount of fish consumed, certain individuals would have mercury intakes approaching the recommended limits. With a view to the future, we believe mercury in fish must continue to be monitored closely in order to assess the risks for the population.

To assess the effect of different methods of classifying food use on principal components analysis (PCA)-derived dietary patterns, and the subsequent impact on estimation of cancer risk associated with the different patterns.

Dietary data were obtained from 232 endometrial cancer cases and 639 controls (Western New York Diet Study) using a 190-item semi-quantitative food-frequency questionnaire. Dietary patterns were generated using PCA and three methods of classifying food use: 168 single foods and beverages; 56 detailed food groups, foods and beverages; and 36 less-detailed groups and single food items.

Classification method affected neither the number nor character of the patterns identified. However, total variance explained in food use increased as the detail included in the PCA decreased (~8%, 168 items to ~17%, 36 items). Conversely, reduced detail in PCA tended to attenuate the odds ratio (OR) associated with the healthy patterns (OR 0.55, 95% confidence interval (CI) 0.35–0.84 and OR 0.77, 95% CI 0.49–1.20, 168 and 36 items, respectively) but not the high-fat patterns (OR 0.95, 95% CI 0.57–1.58 and OR 0.85, 0.51–1.40, 168 and 36 items, respectively).

Greater detail in food-use information may be desirable in determination of dietary patterns for more precise estimates of disease risk.

To define the average food consumption per capita in the Czech population and to investigate food consumption development during the years of economic transition.

Three studies based on the household budget survey (HBS) were conducted in the 1990s. The primary data originated from so-called diaries of reporting households loaned out from the Czech Statistical Office (CSO). The arranging of representative samples has been done and is guaranteed by the CSO. Complementary inquiry was conducted to supplement the HBS data. The average consumption of basic food groups is presented.

All regions of the Czech Republic.

The primary data came from the years 1991, 1994 and 1997. The basic sample representing the Czech population included 420 households and was arranged with regard to the region, size and socio-economic type of households.

The changes in food consumption during the 1990s were reflected, above all, in meat, milk and dairy products, added fats, fruit and beverages. The consumption of poultry meat, fish, fresh fruit and vegetables has increased. The proportion of added fats has changed in favour of vegetable fats. On the other hand, a negative feature may be the permanent reduction in milk consumption.

Most of the changes in eating patterns that appeared in the Czech population after 1989 can be interpreted as positive ones.

To determine the prevalence of vegetarianism and compare food habits among vegetarian and omnivorous adolescents in Sweden and Norway.

Cross-sectional study by questionnaire in Sweden and Norway to gather information about food habits.

The municipalities of Umeå and Stockholm in Sweden, and Bergen in Norway.

In total 2041 ninth-grade students (578 from Umeå, 504 from Stockholm and 959 from Bergen), mean age 15.5 years, were included. The response rate was 95% in Umeå, 91% in Stockholm and 83% in Bergen.

There was a significantly higher prevalence of vegetarianism in Umeå (15.6%) than in Stockholm (4.8%) and Bergen (3.8%). Vegetarians generally wanted more information about a healthy diet and vegetarian females ate dietary supplements to prevent deficiencies more often than omnivorous females (P < 0.01). The young male vegetarians more or less excluded animal products from their diet without changing their food frequency intake or modifying their dietary habits in other respects, while the young female vegetarians more often consumed vegetables and dietary supplements (P < 0.05). However, there was no difference between the intake of fruits/berries, alcoholic beverages, ice cream, sweets/chocolates and fast foods by vegetarians compared with omnivores.

There were three to four times more vegetarians in Umeå than in Stockholm and Bergen. The food habits of the young vegetarians differed from those of omnivorous adolescents and also in some respects from previously published comparative studies of vegetarians' and omnivores' food habits. It is uncertain whether the health benefits shown in previous studies on vegetarianism will be experienced by this young generation of vegetarians.