Healthy dietary patterns have been linked to lower levels of chronic inflammation. The present study aimed to investigate the associations between food group intakes and high-sensitivity C-reactive protein (hsCRP) among community-dwelling adults.

Cross-sectional.

Three areas in Japan (Shiga, Fukuoka, or Kyushu and Okinawa).

The present analysis included 13 648 participants (5126 males and 8522 females; age range, 35–69 years) who had been enrolled in the baseline survey of the Japan Multi-Institutional Collaborative Cohort Study. Food group intakes were estimated using a FFQ. Multiple linear regression was used to examine associations between the quartiles of each energy-adjusted food group intake and log-transformed hsCRP.

The following concentration ratios of hsCRP after comparing the highest and lowest quartiles of food group intake were significant: in males, 1·12 (95 % CI 1·02, 1·22) for processed meat, 1·13 (95 % CI 1·03, 1·24) for fish and 0·83 (95 % CI 0·76, 0·90) for nuts; in females, 0·89 (95 % CI 0·81, 0·97) for bread, 1·11 (95 % CI 1·03, 1·19) for processed meat, 0·86 (95 % CI 0·80, 0·92) for vegetables, 1·19 (95 % CI 1·11, 1·29) for fruit, 0·90 (95 % CI 0·84, 0·97) for nuts and 0·88 (95 % CI 0·82, 0·95) for green tea.

Processed meat and nut intakes were associated with higher and lower hsCRP levels, respectively, in both sexes. However, for several food groups, including fish and fruit, previous findings from dietary pattern analyses were not supported by the present analyses at the food group level.

Although small fish are an important source of micronutrients, the relationship between their intake and mortality remains unclear. This study aimed to clarify the association between intake of small fish and all-cause and cause-specific mortality.

We used the data from a cohort study in Japan. The frequency of the intake of small fish was assessed using a validated FFQ. The hazard ratio (HR) and 95 % confidence interval (CI) for all-cause and cause-specific mortality according to the frequency of the intake of small fish by sex were estimated using a Cox proportional hazard model with adjustments for covariates.

The Japan Multi-Institutional Collaborative Cohort Study.

A total of 80 802 participants (34 555 males and 46 247 females), aged 35–69 years.

During a mean follow-up of 9·0 years, we identified 2482 deaths including 1495 cancer-related deaths. The intake of small fish was statistically significantly and inversely associated with the risk of all-cause and cancer mortality in females. The multivariable-adjusted HR (95 % CI) in females for all-cause mortality according to the intake were 0·68 (0·55, 0·85) for intakes 1–3 times/month, 0·72 (0·57, 0·90) for 1–2 times/week and 0·69 (0·54, 0·88) for ≥ 3 times/week, compared with the rare intake. The corresponding HR (95 % CI) in females for cancer mortality were 0·72 (0·54, 0·96), 0·71 (0·53, 0·96) and 0·64 (0·46, 0·89), respectively. No statistically significant association was observed in males.

Intake of small fish may reduce the risk of all-cause and cancer mortality in Japanese females.

We aimed to examine missing data in FFQ and to assess the effects on estimating dietary intake by comparing between multiple imputation and zero imputation.

We used data from the Okazaki Japan Multi-Institutional Collaborative Cohort (J-MICC) study. A self-administered questionnaire including an FFQ was implemented at baseline (FFQ1) and 5-year follow-up (FFQ2). Missing values in FFQ2 were replaced by corresponding FFQ1 values, multiple imputation and zero imputation.

A methodological sub-study of the Okazaki J-MICC study.

Of a total of 7585 men and women aged 35–79 years at baseline, we analysed data for 5120 participants who answered all items in FFQ1 and at least 50% of items in FFQ2.

Among 5120 participants, the proportion of missing data was 3·7%. The increasing number of missing food items in FFQ2 varied with personal characteristics. Missing food items not eaten often in FFQ2 were likely to represent zero intake in FFQ1. Most food items showed that the observed proportion of zero intake was likely to be similar to the probability that the missing value is zero intake. Compared with FFQ1 values, multiple imputation had smaller differences of total energy and nutrient estimates, except for alcohol, than zero imputation.

Our results indicate that missing values due to zero intake, namely missing not at random, in FFQ can be predicted reasonably well from observed data. Multiple imputation performed better than zero imputation for most nutrients and may be applied to FFQ data when missing is low.