The contribution of dietary saturated fatty acids (SFA) to cardiovascular disease (CVD) and mortality remains debated after decades of research. Few previous studies had repeated dietary assessments and power to assess mortality. Evidence for individual SFA is limited. In this large population-based cohort study, we investigated associations between intake of total and individual SFA and risk of total and CVD mortality. Adult residents (mean 41·1 years at baseline) in three Norwegian counties were invited to repeated health screenings between 1974 and 1988 (> 80 % attendance). We calculated cumulative average intakes of macronutrients from semi-quantitative FFQ. Median (interquartile range) intake of SFA was 14·6 % (12·8–16·6 %) of total energy (E%). Hazard ratios (HR) and 95 % CI were estimated using multivariable Cox regression models to assess total, CVD, ischaemic heart disease (IHD) and acute myocardial infarction (AMI) mortality. Among 78 725 participants, 28 555 deaths occurred during a median follow-up of 33·5 years, with 9318 deaths due to CVD. Higher intake of SFA (replacing carbohydrates) was positively associated with all mortality endpoints, including total (HR per 5 E% increment, 1·18; 95 % CI 1·13, 1·23) and CVD mortality (1·16; 95 % CI 1·07, 1·25). Theoretical isoenergetic substitution of SFA with carbohydrates or MUFA was associated with lower risk. Of individual SFA, myristic (14:0) and palmitic acid (16:0) were positively associated with mortality. In summary, dietary SFA intake was strongly associated with higher total and CVD mortality in this long-term cohort study. This supports policies implemented to reduce SFA consumption in favour of carbohydrates and unsaturated fats.

We aimed to validate a method for assessing trans-fatty acid (TFA) intake in the Japanese population using the FFQ developed in the 1990s from a prospective study that was based on the Japan Public Health Center-based Prospective Cohort Study. For FFQ validation, we included 565 participants (Cohort I: n 215, Cohort II: n 350) aged 40–69 years. We used a 28-d dietary record (DR) over 1 year and two FFQ administered before and after DR assessment. We calculated total TFA intake, TFA from industrial oils (i-TFA) and TFA from ruminants (r-TFA) considering a database of measurements obtained mainly from Japan. Spearman’s rank correlation coefficients (CC) were computed for validity and reproducibility. Energy adjustments were applied using two methods considering the TFA measurement: density method for TFA % of total energy and residual method for TFA g/d. The total TFA intake (% of the total energy intake) was 0·08–0·76 % (median, 0·27–0·37 %) in DR of both cohorts and was 0·00–1·13 % (median, 0·30–0·40 %) in FFQ. The i-TFA accounted for approximately 50 % of the total TFA intake in DR and approximately 40 % in FFQ. For total TFA (% of the total energy intake), CC were 0·54–0·69, and weighted κ coefficients were 0·88–0·92 for both cohorts. The de-attenuated CC was 0·46–0·62 for i-TFA (g/d) and 0·57–0·68 for r-TFA (g/d). Our study showed that the validity and reproducibility of TFA intake estimation using the FFQ were reasonable, suggesting its suitability among the Japanese population with low-TFA intake.

Several countries have issued dietary recommendations about total and specific fatty acid (FA) intake for the prevention of CHD. For many years until today, controversies have existed especially about the deleterious effect or not of SFA, and the protective effect or not of n-3 PUFA, so that some authors have criticised these recommendations. There are many reasons for these controversies, including the different conclusions of prospective cohort studies compared with randomised clinical trials (RCT), and the contradictory conclusions of meta-analyses depending on the quality, number and type of studies included. The interrelationships between different FA in the diet make it difficult to analyse the specific effect of a particular class of FA on CHD. Furthermore, based on clinical practice and effectiveness of population-based prevention, it is very difficult at the individual level to assess in personal dietary intake the actual percentage and/or amount of SFA contained in each meal or consumed daily/weekly. In this critical narrative review, we try to answer the question of whether it would not be more relevant, in 2020, to promote dietary patterns, rather than FA intake recommendations. We critically analyse past and recent data on the association of FA with CHD, then propose that the Mediterranean diet and Japanese diet should be revitalised for Westerners and Asian populations, respectively. This does not exclude the usefulness of continuing research about effects of FA towards CHD, and accepting that what seems true today might be revised, at least partially tomorrow.

Human milk fatty acid composition varies during lactation and is influenced by maternal diet, maternal lifestyle-related factors and genetic background. This is one of the first studies to investigate a period effect, that is, the impact of lifestyle-related changes on human milk fatty acid composition, in two different cohorts. Lactating women were recruited from the general population a decade apart in Ulm, Germany, using similar methodology. Human milk samples collected 6 weeks postpartum were analysed (Ulm Birth Cohort Study (UBCS (2000)), n 567; Ulm SPATZ Health Study (SPATZ (2012)), n 458). Centred log ratio transformation was applied to fatty acid data. Principal component analysis was used to determine study-dependent fatty acid profiles. A general linear model was used to determine the study (or period) effect on fatty acid profiles adjusting for duration of gestation, age, education, delivery mode, smoking and pre-pregnancy BMI. Two principal components were retained (PC1 and PC2). PC1 was associated with UBCS, while PC2 was associated with SPATZ. PC1 comprised high SFA, and low MUFA, n-6 and n-3 long-chain PUFA (LCPUFA). The inverse was true for PC2. Although human milk remains a source of essential fatty acids, infants could be at risk of inadequate n-3 and n-6 LCPUFA intake through human milk. The differences in the human milk fatty acid profiles also reflect changes in maternal dietary habits in the more recent cohort, which may comprise lower intakes of dietary trans-fatty acids and SFA and higher intakes of vegetable oils.

The gut microbiota is directly influenced by dietary components, and it plays critical roles in chronic diseases. Excessive consumption of trans-fatty acids (TFA) is associated with obesity induced by alterations in gut microbiota, but the links between obesity and gut microbiota remain unclear. Therefore, studies examining the impact of TFA on intestinal microflora are essential. In our study, we performed 16S ribosomal RNA gene sequencing on faecal samples from Sprague–Dawley rats fed a basal diet (control (CON) group), high-fat (HF) diet (diet-induced obesity (DIO) group) or TFA diets (1 % TFA group and 8 % TFA group) for 8 weeks to investigate the effects of TFA/HF diets on obesity and gut microbiota composition. We found that the TFA/HF diets significantly induced obesity and changes in blood and brain physiological parameters of the rats. The relative abundance of the phyla Firmicutes and Bacteroidetes was inversely altered in the three test groups compared with the CON group. Proteobacteria increased slightly in the DIO, 1 % TFA and 8 % TFA groups. The genus Bacteroides increased in the DIO and 1 % TFA groups, but Muribaculaceae decreased in all experimental groups compared with the CON group. Moreover, significant differences were observed among clusters of orthologous group functional categories of the four dietary groups. Our observations suggested that the TFA/HF diets induced obesity and dysfunction of gut microbiota. Gut dysbiosis might mediate the obesity effects of TFA/HF diets.

Street food is part of the culture in central Asia. Although nourishing food can be found, unhealthier options are becoming increasingly popular – a marker of nutrition transition. The nutritional composition of street food in urban settings is, however, unknown. The objective of the present study was, thus, to characterise the street food availability in Dushanbe, Tajikistan. A total of 800 street food vending sites in public markets were selected through random and systematic procedures. Trained interviewers collected data on vending sites’ characteristics, location and food available. Samples of the most commonly available food were collected (ninety-nine homemade and thirty-five industrial). Macronutrients were quantified through proximate analysis. Fruit, drinks and food other than fruits were available, respectively, in 4·5, 40·5 and 87·4 %, of the vending sites. Among the latter, 63·6 % sold only homemade (e.g. bread, traditional dishes, snacks, pastries, sandwiches and cakes), 19·3 % only industrial (e.g. bread, snacks, pastries and cookies) and 17·1 % both types of food. Homemade food presented higher energy per serving compared with industrial food (median 452 v. 276 kcal/serving (1891 v. 1155 kJ/serving); P < 0·001). A high content of SFA (soup: 10·9 g/serving) and trans-fatty acids (cakes: 1·8 g/serving) was also found in homemade food. However, industrial wafers showed the highest content of these fatty acids (12·9 g/serving and 2·5 g/serving, respectively). Soft drinks were available in 68·5 % of the vending sites selling beverages. Homemade and industrial street food, with heterogeneous nutritional value, were widely available in Dushanbe. Hence, policies promoting the availability of healthy food should be encouraged.

Human milk covers the infant’s nutrient requirements during the first 6 months of life. The composition of human milk progressively changes during lactation and it is influenced by maternal nutritional factors. Nowadays, it is well known that nutrients have the ability to interact with genes and modulate molecular mechanisms impacting physiological functions. This has led to a growing interest among researchers in exploring nutrition at a molecular level and to the development of two fields of study: nutrigenomics, which evaluates the influence of nutrients on gene expression, and nutrigenetics, which evaluates the heterogeneous individual response to nutrients due to genetic variation. Fatty acids are one of the nutrients most studied in relation to lactation given their biologically important roles during early postnatal life. Fatty acids modulate transcription factors involved in the regulation of lipid metabolism, which in turn causes a variation in the proportion of lipids in milk. This review focuses on understanding, on the one hand, the gene transcription mechanisms activated by maternal dietary fatty acids and, on the other hand, the interaction between dietary fatty acids and genetic variation in genes involved in lipid metabolism. Both of these mechanisms affect the fatty acid composition of human milk.

The quality of dietary lipids in the maternal diet can programme the offspring to diseases in later life. We investigated whether the maternal intake of palm oil or interesterified fat, substitutes for trans-unsaturated fatty acids (FA), induces metabolic changes in the adult offspring. During pregnancy and lactation, C57BL/6 female mice received normolipidic diets containing partially hydrogenated vegetable fat rich in trans-unsaturated fatty acids (TG), palm oil (PG), interesterified fat (IG) or soyabean oil (CG). After weaning, male offspring from all groups received the control diet until day 110. Plasma glucose and TAG and liver FA profiles were ascertained. Liver mitochondrial function was accessed with high-resolution respirometry by measuring VO2, fluorimetry for detection of hydrogen peroxide (H2O2) production and mitochondrial Ca2+ uptake. The results showed that the IG offspring presented a 20 % increase in plasma glucose and both the IG and TG offspring presented a 2- and 1·9-fold increase in TAG, respectively, when compared with CG offspring. Liver MUFA and PUFA contents decreased in the TG and IG offspring when compared with CG offspring. Liver MUFA content also decreased in the PG offspring. These modifications in FA composition possibly affected liver mitochondrial function, as respiration was impaired in the TG offspring and H2O2 production was higher in the IG offspring. In addition, mitochondrial Ca2+ retention capacity was reduced by approximately 40 and 55 % in the TG and IG offspring, respectively. In conclusion, maternal consumption of trans-unsaturated and interesterified fat affected offspring health by compromising mitochondrial bioenergetics and lipid metabolism in the liver.

Nutrition during pregnancy can impact on the susceptibility of the offspring to CVD. Postnatal consumption of trans-fatty acids (TFA), associated with partially hydrogenated vegetable oil (PHVO), increases the risk of atherosclerosis, whereas evidence for those TFA associated with ruminant-derived dairy products and meat remain equivocal. In this study, we investigate the impact of maternal consumption of dietary PHVO (P) and ruminant milk fat (R) on the development of atherosclerosis in their offspring, using the transgenic apoE*3 Leiden mouse. Dams were fed either chow (C) or one of three high-fat diets: a diet reflecting the SFA content of a ‘Western’ diet (W) or one enriched with either P or R. Diets were fed during either pregnancy alone or pregnancy and lactation. Weaned offspring were then transferred to an atherogenic diet for 12 weeks. Atherosclerosis was assessed as lipid staining in cross-sections of the aorta. There was a significant effect of maternal diet during pregnancy on development of atherosclerosis (P=0·013) in the offspring with those born of mothers fed R or P during pregnancy displaying smaller lesions that those fed C or W. This was not associated with changes in total or lipoprotein cholesterol. Continuing to feed P during lactation increased atherosclerosis compared with that seen in offspring of dams fed P only during pregnancy (P<0·001). No such effect was seen in those from mothers fed R (P=0·596) or W (P=901). We conclude that dietary TFA have differing effects on cardiovascular risk at different stages of the lifecycle.

Generally, there is a need for short questionnaires to estimate diet quality in the Netherlands. We developed a thirty-four-item FFQ – the Dutch Healthy Diet FFQ (DHD-FFQ) – to estimate adherence to the most recent Dutch guidelines for a healthy diet of 2006 using the DHD-index. The objectives of the present study were to evaluate the DHD-index derived from the DHD-FFQ by comparing it with the index based on a reference method and to examine associations with participant characteristics, nutrient intakes and levels of cardiometabolic risk factors. Data of 1235 Dutch men and women, aged between 20 and 70 years, participating in the Nutrition Questionnaires plus study were used. The DHD-index was calculated from the DHD-FFQ and from a reference method consisting of a 180-item FFQ combined with a 24-h urinary Na excretion value. Ranking was studied using Spearman’s correlations, and absolute agreement was studied using a Bland–Altman plot. Nutrient intakes derived from the 180-item FFQ were studied according to quintiles of the DHD-index using DHD-FFQ data. The correlation between the DHD-index derived from the DHD-FFQ and the reference method was 0·56 (95 % CI 0·52, 0·60). The Bland–Altman plot showed a small mean overestimation of the DHD-index derived from the DHD-FFQ compared with the reference method. The DHD-index score was in the favourable direction associated with most macronutrient and micronutrient intakes when adjusted for energy intake. No associations between the DHD-index score and cardiometabolic risk factors were observed. In conclusion, the DHD-index derived from the DHD-FFQ was considered acceptable in ranking but relatively poor in individual assessment of diet quality.

The present study explored the relationships between fried food consumption and metabolic risk factors and hypertension in Korean adults. The study was based on the fifth Korean National Health and Nutrition Examination Survey between 2010 and 2011. A total of 9221 Korean adults aged ≥19 years were studied. Fried food consumption was assessed using a validated FFQ. Metabolic risk factors such as waist circumference, fasting plasma glucose (FPG), TAG, HDL-cholesterol and systolic and diastolic blood pressure (SBP and DBP) were measured. Hypertension was defined as SBP≥140 mmHg, DBP≥90 mmHg or current use of antihypertensive medication. Adjusted OR for elevated blood pressure significantly increased in men (OR 1·62; 95 % CI 1·11, 2·37; Ptrend=0·0447) and women (OR 2·20; 95 % CI 1·21, 4·00; Ptrend=0·0403) with a greater than twice a week consumption of fried food compared with those who rarely consumed fried food. However, fried food consumption was not associated with other metabolic risk factors (abdominal obesity, high FPG, hypertriacylglycerolaemia, low HDL-cholesterol and the metabolic syndrome). The adjusted OR for hypertension increased by 2·4-fold in women (OR 2·37; 95 % CI 1·19, 4·72; Ptrend=0·0272) with a greater than twice a week fried food consumption compared with those who rarely consumed it. No significant association was found between fried food consumption and hypertension in men. This study suggests that frequent fried food consumption is associated with hypertension in Korean women. Further studies are needed to investigate the effect of different types of fried foods on hypertension.

Although cross-sectional studies have shown a positive association between Se and cholesterol concentrations, a recent randomised controlled trial in 501 elderly UK individuals of relatively low-Se status found that Se supplementation for 6 months lowered total plasma cholesterol. The Danish PRECISE (PREvention of Cancer by Intervention with Selenium) pilot study (ClinicalTrials.gov ID: NCT01819649) was a 5-year randomised, double-blinded, placebo-controlled trial with four groups (allocation ratio 1:1:1:1). Men and women aged 60–74 years (n 491) were randomised to 100 (n 124), 200 (n 122) or 300 (n 119) μg Se-enriched yeast or matching placebo-yeast tablets (n 126) daily for 5 years. A total of 468 participants continued the study for 6 months and 361 participants, equally distributed across treatment groups, continued for 5 years. Plasma samples were analysed for total and HDL-cholesterol and for total Se concentrations at baseline, 6 months and 5 years. The effect of different doses of Se supplementation on plasma lipid and Se concentrations was estimated by using linear mixed models. Plasma Se concentration increased significantly and dose-dependently in the intervention groups after 6 months and 5 years. Total cholesterol decreased significantly both in the intervention groups and in the placebo group after 6 months and 5 years, with small and nonsignificant differences in changes in plasma concentration of total cholesterol, HDL-cholesterol, non-HDL-cholesterol and total:HDL-cholesterol ratio between intervention and placebo groups. The effect of long-term supplementation with Se on plasma cholesterol concentrations or its sub-fractions did not differ significantly from placebo in this elderly population.