The relationship between nut intake and risk of colorectal cancer: a case control study.
Nutrition journal. 2018;17(1):37
Plain language summary
Nut consumption has been shown to be associated with reduced risk of obesity, Type 2 diabetes and cardiovascular disease. This retrospective, case-controlled study aimed to examine the association between nut consumption and the risk of colo-rectal cancer in a cohort of Korean adults. 923 colorectal cancer patients and 1846 controls were included in the study. Each completed a validated food frequency questionnaire, including peanuts, pine nuts and almonds. A nut serving was considered to be 15g and was categorised as none, less than 1 serving per week, 1-3 servings per week and greater than 3 servings per week. Nut consumption was found to have a strong association with reduced colo-rectal cancer in both men and women, after adjusting for age, education level, alcohol consumption, BMI, regular exercise, red meat intake, fruit and vegetable intake and total energy intake. This association was found in all sub-sites of the colon for men and for the distal and rectum subsites for women.
BACKGROUND Nut consumption is known to reduce the risk of obesity, diabetes mellitus, and cardiovascular disease. However, in previous studies, portion sizes and categories of nut consumption have varied, and few studies have assessed the association between colorectal cancer risk and nut consumption. In this study, we investigated the relationship between nut consumption and colorectal cancer risk. METHODS A case-control study was conducted among 923 colorectal cancer patients and 1846 controls recruited from the National Cancer Center in Korea. Information on dietary intake was collected using a semi-quantitative food frequency questionnaire with 106 items, including peanuts, pine nuts, and almonds (as 1 food item). Nut consumption was categorized as none, < 1 serving per week, 1-3 servings per week, and ≥3 servings per week. A binary logistic regression model was used to estimate odds ratios (OR) and their 95% confidence intervals (CI) for the association between nut consumption and colorectal cancer risk, and a polytomous logistic regression model was used for sub-site analyses. RESULTS High nut consumption was strongly associated with reduced risk of colorectal cancer among women (adjusted ORs: 0.30, 95%CI: 0.15-0.60 for the ≥3 servings per week group vs. none). A similar inverse association was observed for men (adjusted ORs: 0.28, 95% CI: 0.17-0.47). In sub-site analyses, adjusted ORs (95% CIs) comparing the ≥3 servings per week group vs none were 0.25 (0.09-0.70) for proximal colon cancer, 0.39 (0.19-0.80) for distal colon cancer, and 0.23 (0.12-0.46) for rectal cancer among men. An inverse association was also found among women for distal colon cancer (OR: 0.13, 95% CI: 0.04-0.48) and rectal cancer (OR: 0.40, 95% CI: 0.17-0.95). CONCLUSIONS We found a statistically significant association between high frequency of nut consumption and reduced risk of colorectal cancer. This association was observed for all sub-sites of the colon and rectum among both men and women, with the exception of proximal colon cancer for women.
Consumption of ultra-processed foods and cancer risk: results from NutriNet-Santé prospective cohort.
BMJ (Clinical research ed.). 2018;360:k322
Plain language summary
Foods that are heavily processed tend to have high levels of total fat, sugar and salt and low levels of fibre and vitamins. They also tend to have high levels of contaminants (caused for example by high heat treatment), food additives and plastic packaging exposure. This large prospective population-based cohort study assessed the association between ultra-processed food consumption and the incidence of cancer. The study found that ultra-processed food intake was associated with a higher overall cancer risk and a higher breast cancer risk. A 10% increase in the consumption of ultra-processed foods was associated with an increase of more than 10% greater risk of overall and breast cancer risk. The authors call for further studies to better understand the different elements of food processing and their association to cancer risk.
OBJECTIVE To assess the prospective associations between consumption of ultra-processed food and risk of cancer. DESIGN Population based cohort study. SETTING AND PARTICIPANTS 104 980 participants aged at least 18 years (median age 42.8 years) from the French NutriNet-Santé cohort (2009-17). Dietary intakes were collected using repeated 24 hour dietary records, designed to register participants' usual consumption for 3300 different food items. These were categorised according to their degree of processing by the NOVA classification. MAIN OUTCOME MEASURES Associations between ultra-processed food intake and risk of overall, breast, prostate, and colorectal cancer assessed by multivariable Cox proportional hazard models adjusted for known risk factors. RESULTS Ultra-processed food intake was associated with higher overall cancer risk (n=2228 cases; hazard ratio for a 10% increment in the proportion of ultra-processed food in the diet 1.12 (95% confidence interval 1.06 to 1.18); P for trend<0.001) and breast cancer risk (n=739 cases; hazard ratio 1.11 (1.02 to 1.22); P for trend=0.02). These results remained statistically significant after adjustment for several markers of the nutritional quality of the diet (lipid, sodium, and carbohydrate intakes and/or a Western pattern derived by principal component analysis). CONCLUSIONS In this large prospective study, a 10% increase in the proportion of ultra-processed foods in the diet was associated with a significant increase of greater than 10% in risks of overall and breast cancer. Further studies are needed to better understand the relative effect of the various dimensions of processing (nutritional composition, food additives, contact materials, and neoformed contaminants) in these associations. STUDY REGISTRATION Clinicaltrials.gov NCT03335644.