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.

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.

Pattern analysis has emerged as a tool to depict the role of multiple nutrients/foods in relation to health outcomes. The present study aimed at extracting nutrient patterns with respect to breast cancer (BC) aetiology.

Nutrient patterns were derived with treelet transform (TT) and related to BC risk. TT was applied to twenty-three log-transformed nutrient densities from dietary questionnaires. Hazard ratios (HR) and 95 % confidence intervals computed using Cox proportional hazards models quantified the association between quintiles of nutrient pattern scores and risk of overall BC, and by hormonal receptor and menopausal status. Principal component analysis was applied for comparison.

The European Prospective Investigation into Cancer and Nutrition (EPIC).

Women (n 334 850) from the EPIC study.

The first TT component (TC1) highlighted a pattern rich in nutrients found in animal foods loading on cholesterol, protein, retinol, vitamins B12 and D, while the second TT component (TC2) reflected a diet rich in β-carotene, riboflavin, thiamin, vitamins C and B6, fibre, Fe, Ca, K, Mg, P and folate. While TC1 was not associated with BC risk, TC2 was inversely associated with BC risk overall (HRQ5 v. Q1=0·89, 95 % CI 0·83, 0·95, Ptrend<0·01) and showed a significantly lower risk in oestrogen receptor-positive (HRQ5 v. Q1=0·89, 95 % CI 0·81, 0·98, Ptrend=0·02) and progesterone receptor-positive tumours (HRQ5 v. Q1=0·87, 95 % CI 0·77, 0·98, Ptrend<0·01).

TT produces readily interpretable sparse components explaining similar amounts of variation as principal component analysis. Our results suggest that participants with a nutrient pattern high in micronutrients found in vegetables, fruits and cereals had a lower risk of BC.

To investigate the usefulness of serum carotenoids as biomarkers of fruit and vegetable consumption.

Reproducibility study on three repeat measurements of serum carotenoids. Correlation analysis of carotenoids and dietary food intake, and regression analysis of potential predictive parameters for serum carotenoid levels.

New York, USA.

Women participating in the New York Women's Health Study, a prospective study of sex hormones, diet and breast cancer. Forty-eight women with three repeat blood samples and 302 women having a blood sample and a dietary history questionnaire.

Serum carotenoid concentrations were highly reproducible between one- and two-year repeat samples. Estimated fruit and vegetable consumption was positively correlated with serum carotenoid concentrations but correlation coefficients were low. Consumption of fruit was predictive for serum levels of beta-carotene, alpha-carotene and beta-cryptoxanthin, while vegetable consumption was predictive for serum beta-carotene, lutein, zeaxanthin and lycopene. Serum concentrations of cholesterol and triglycerides were predictive for serum carotenoids but adjustment for their levels had little or no influence on the correlation between fruit and vegetable consumption and serum carotenoid concentrations.

One single serum measurement of alpha-carotene, beta-carotene and lutein can accurately rank subjects according to their usual serum level. Serum concentrations, however, correlate only moderately with estimated dietary intake of fruits or vegetables and should therefore be used with caution as biomarkers of fruit and vegetable intake.