To determine the level of adherence and to assess the association between higher adherence to the South African food based dietary guidelines (SAFBDG) and breast cancer risk.

Population-based, case–control study (the South African Breast Cancer study) matched on age and demographic settings. Validated questionnaires were used to collect dietary and epidemiological data. To assess adherence to the SAFBDG, a nine-point adherence score (out of eleven guidelines) was developed, using suggested adherence cut-points for scoring each recommendation (0 and 1). When the association between higher adherence to the SAFBDG and breast cancer risk was assessed, data-driven tertiles among controls were used as cut-points for scoring each recommendation (0, 0·5 and 1). OR and 95 % CI were estimated using multivariate logistic regression models.

Soweto, South Africa.

Black urban women, 396 breast cancer cases and 396 controls.

After adjusting for potential confounders, higher adherence (>5·0) to the SAFBDG v. lower adherence (<3·5) was statistically significantly inversely associated with breast cancer risk overall (OR = 0·56, 95 % CI 0·38, 0·85), among postmenopausal women (OR = 0·64, 95 % CI 0·40, 0·97) as well as for oestrogen-positive breast cancers (OR = 0·51, 95 % CI 0·32, 0·89). Only 32·3 % of cases and 39·1 % of controls adhered to at least half (a score >4·5) of the SAFBDG.

Higher adherence to the SAFBDG may reduce breast cancer risk in this population. The concerning low levels of adherence to the SAFBDG emphasise the need for education campaigns and to create healthy food environments in South Africa to increase adherence to the SAFBDG.

Fatty acids (FA) are highly active molecules involved in different metabolic pathways. Several FA have direct tumorigenic effects in animal and cell-line models and recent epidemiological studies also suggest associations with cancer risk. Some of these health effects are associated with the phospholipid (PL) FA composition of cell membranes what may be related to dietary FA intake. This study aims to assess the correlation between FA intake and the plasma PL FA status in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort.

Dietary intake of individual FA was estimated using centre-specific validated dietary questionnaires and the National Nutrient Database for Standard Reference of the United States. Circulating levels of 60 individual PL FA were measured in baseline venous plasma phospholipid samples in nested case-controls studies within the EPIC cohort (n = 9,996). The fatty acid composition in the phospholipid fraction was measured by gas chromatography in plasma samples. Spearman rank correlations were calculated to determine associations between FA intakes and plasma PL levels.

Results indicated low to moderately high associations between FA intake and plasma levels. Low correlations were found between intakes of total saturated FA or total monounsaturated FA and plasma levels. Moderate positive correlations were particularly found for long-chain n-3 poly-unsaturated FA (r = 0.35) with the highest (r = 0.41) for n-3 PUFA docosahexaenoic acid (DHA). Moderately high correlations were found for the exogenous trans-FA (r = 0.53 for total trans-FA; r = 0.48 for industrial trans-FA (elaidic acid)). Sensitivity analysis showed some attenuation of most correlations among cancer cases compared to controls.

Our findings suggest that dietary FA intake influences the plasma PL FA status to a certain extent for several FA isomers, particularly those that are not or less efficiently endogenously produced. As diet is a modifiable risk factor, these findings are important for future public health strategies focusing on cancer prevention. Although the level of detail in dietary questionnaires is rather limited, these results are showing their potential to assess the intake of FA isomers in large-scale populations where biological measurements are not feasible for the full cohort.

The consumption of ultra-processed foods (UPF) has been linked to an increased risk of cancer in western populations, particularly for breast cancer (BC). Although the consumption of UPF is increasing rapidly in Latin American (LA) populations too, there has been no evaluation of its association with BC among LA women, where 20% of the BC cases present at ages younger than 45 years. We therefore evaluated the role of UPF intake on BC risk in young women participating in the Latin American PRECAMA study.

The PRECAMA study is an ongoing study coordinated by the International Agency for Research on Cancer (IARC) and involves scientific teams in four LA countries (Chile, Colombia, Costa Rica and Mexico); 406 incident BC cases and population based controls aged 20–45 years are recruited. Trained nurses administered a lifestyle and food frequency questionnaires (FFQ), conducted anthropometric measurements and collected biological samples. Tumour receptor status are determined in a centralized laboratory. UPF consumption was estimated by applying the NOVA classification to the dietary consumption data obtained via the FFQs. The association of the consumption of UPF and BC was determined using conditional logistic regression analysis adjusting for potential confounding factors.

The median age at recruitment was 40 years. The median percentage of calories from UPF was 24% (10th to 90th percentile: 9 to 43%). UPF intake was positively associated with BC risk (OR for tertiles 2 and 3 in comparison with tertile 1 were 1.84 (95% CI 1.21 -2.81) and 1.69 (95% CI 0.99 -2.89) respectively). Among the UPF most strongly associated with BC, we identified the intake of industrial bread, packaged sweet and savoury snacks, breakfast cereals, cakes and desserts, and ready-eat/fast food. Comparing the 3rd with the 1st tertile of energy intake from the UPF group “fast food” the OR for BC risk was 1.93 (95% CI 1.23–3.04).

Our results show positive associations between the consumption of UPF and BC risk in young women in LA. Therefore, global actions to decrease UPF intakes are urgently needed to address the cancer burden. In addition, further studies are needed to disentangle mechanisms relating UPF intake and carcinogenic processes in the breast. The European Prospective Investigation into Cancer and Nutrition (EPIC) study, a large-scale cohort including ~500,000 participants and 18,814 BC cases will be used to unravel the mechanistic pathways underlying these positive associations between the consumption of UPF and BC risk.

Psychosocial stressors deriving from socioeconomic disadvantages in adolescents can result in higher metabolic syndrome (MetS) risk. We aimed to examine whether socioeconomic disadvantages were associated with MetS independent of lifestyle and whether there was a dose response relationship between the number of cumulated socioeconomic disadvantages and the risk of MetS.

The present study included 1,037 European adolescents (aged 12.5–17.5) of the 3,528 total HELENA participants. Sociodemographic variables and lifestyle were assessed through self-reported questionnaires. Disadvantaged groups included adolescents with low educated parents, low family affluence, migrant origin, unemployed parents, and from non-traditional families. MetS score was calculated as the sum of sex- and age-specific z-scores of waist circumference, HOMA-IR index, mean of z-scores of diastolic and systolic blood pressure and mean of z-score of HDL-C multiplied by -1 and z-score of TG. A higher score indicates poor metabolic health. Linear mixed-effects models were used to study the association between social disadvantages and MetS risk score. Models were adjusted for sex, age, pubertal status (Tanner stage) and lifestyle (diet quality, physical activity, alcohol consumption and smoking status).

Adolescents with low educated mothers showed a higher MetS score (0.54 [0.09–0.98]; β [99% confidence interval]) compared to high-educated mothers. Adolescents who accumulated more than three disadvantages (0.69 [0.08–1.31]) or with missing information on disadvantages (0.72 [0.04–1.40]) had a higher MetS risk compared to non-socioeconomically disadvantaged groups. Stronger associations between socioeconomic disadvantages and MetS were found in male in comparison with female adolescents.

Out of the studied socioeconomic disadvantages, maternal education is the most important determinant of adolescent's MetS risk independently of sex, age, Tanner stage, smoking status, alcohol consumption, diet quality and physical activity. Social vulnerabilities (migrant background, unemployment status and belonging to a non-traditional family) were not associated with a higher MetS risk in European adolescents. However, we found a dose-response relationship between the number of factors related to social disadvantage and adolescents’ MetS risk with adolescents accumulating three or more socioeconomic disadvantages showing the highest risk. Stronger associations between socioeconomic disadvantages and MetS were found in male compared to female adolescents. Policy makers should focus on low educated families to tackle health disparities.

To investigate whether adherence to the adapted Mediterranean Diet Score for Adolescents (MDS_A) and the adapted Mediterranean Diet Quality Index for Adolescents (KIDMED_A) is associated with better food/nutrient intakes and nutritional biomarkers.

The Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study is a cross-sectional study aiming to obtain comparable data on a variety of nutritional and health-related parameters in European adolescents aged 12·5–17·5 years.

Nine European countries.

European adolescents (n 2330) recruited to the HELENA study. Dietary intake was obtained with 24 h dietary recalls, an FFQ and a Food Choices and Preferences questionnaire. MDS_A was calculated as a categorical variable using cut-offs (MDS_A), as a continuous variable (zMDS_A) and with energy adjustments (zEnMDS_A). The KIDMED_A score was also calculated.

Multilevel linear regression analysis showed positive associations for zMDS_A and KIDMED_A with serum levels of vitamin D, vitamin C, plasma folate, holo-transcobalamin, β-carotene and n-3 fatty acids, while negative associations were observed with trans-fatty acid serum levels. For categorical indices, blood biomarkers showed few significant results. zMDS_A and KIDMED_A showed positive associations with vegetables and fruits intake, and negative associations with energy-dense and low-nutritious foods. zMDS_A and KIDMED_A were positively associated with all macronutrients, vitamins and minerals (all P < 0·0001), except with monosaccharides and PUFA for KIDMED_A and cholesterol for both indices (P < 0·05).

zMDS_A and KIDMED_A have shown the strongest associations with the dietary indicators and biomarkers that have been associated with the Mediterranean diet before, and are therefore considered the most appropriate and valid Mediterranean diet scores for European adolescents.

We evaluated the relationship between food availability, as the only dietary exposure data available across Africa, and age-standardised cancer incidence rates (ASR) in eighteen countries.

Ecological study.

Availability of food groups and dietary energy was considered for five hypothetical time points: years of collection of ASR (T0) and 5, 10, 15 and 20 preceding years (T–5, T–10, T–15, T–20). Ecological correlations adjusted for human development index, smoking and obesity rates were calculated to evaluate the relationship between food availability and ASR of breast, prostate, colorectal, oesophageal, pancreatic, stomach and thyroid cancer.

Red meat was positively correlated with pancreatic cancer in men (T–20: r–20 = 0·61, P < 0·05), stomach cancer in women (T0: r0 = 0·58, P < 0·05), and colorectal cancer in men (T0: r0 = 0·53, P < 0·05) and women (T–20: r–20 = 0·58, P < 0·05). Animal products including meat, animal fats and higher animal-sourced energy supply tended to be positively correlated with breast, colorectal, pancreatic, stomach and thyroid cancer. Alcoholic beverages were positively correlated to oesophageal cancer in men (r0 = 0·69, P < 0·001) and women (r–20 = 0·72, P < 0·001).

The present analysis provides initial insights into the impact of alcoholic beverages, and increasing use of animal over plant products, on the incidence of specific cancers in Africa. The findings support the need for epidemiological studies to investigate the role of diet in cancer development in Africa.

To investigate dietary sources of Ca and vitamin D (VitD) intakes, and the associated sociodemographic and lifestyle factors, among European adolescents.

Linear regression mixed models were used to examine sex-specific associations of Ca and VitD intakes with parental education, family affluence (FAS), physical activity and television (TV) watching while controlling for age, Tanner stage, energy intake and diet quality.

The Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA)Cross-Sectional Study.

Adolescents aged 12·5–17·5 years (n 1804).

Milk and cheese were the main sources of Ca (23 and 19 % contribution to overall Ca intake, respectively). Fish products were the main VitD source (30 % contribution to overall VitD intake). Ca intake was positively associated with maternal education (β=56·41; 95 % CI 1·98, 110·82) and negatively associated with TV viewing in boys (β=–0·43; 95 % CI −0·79, −0·07); however, the significance of these associations disappeared when adjusting for diet quality. In girls, Ca intake was positively associated with mother’s (β=73·08; 95 % CI 34·41, 111·74) and father’s education (β=43·29; 95 % CI 5·44, 81·14) and FAS (β=37·45; 95 % CI 2·25, 72·65). This association between Ca intake and mother’s education remained significant after further adjustment for diet quality (β=41·66; 95 % CI 0·94, 82·38). Girls with high-educated mothers had higher Ca intake.

Low-educated families with poor diet quality may be targeted when strategizing health promotion programmes to enhance dietary Ca.