Ultra-processed Foods and Risk of Crohn's Disease and Ulcerative Colitis: A Prospective Cohort Study.

BACKGROUND & AIMS: The rising incidence of inflammatory bowel disease in regions undergoing Westernization has coincided with the increase in ultra-processed food (UPF) consumption over the past few decades. We aimed to examine the association between consumption of UPFs and the risk of Crohn's disease (CD) and ulcerative colitis (UC). METHODS: We performed a prospective cohort study of 3 nationwide cohorts of health professionals in the United States-the Nurses' Health Study (1986-2014), the Nurses' Health Study II (1991-2017), and the Health Professionals Follow-up Study (1986-2012). We employed Cox proportional hazards models with adjustment for confounders to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) for CD and UC according to self-reported consumption of UPFs. RESULTS: The study included 245,112 participants. Over 5,468,444 person-years of follow-up, we documented 369 incident cases of CD and 488 incident cases of UC. The median age at diagnosis was 56 years (range, 29-85 years). Compared with participants in the lowest quartile of simple updated UPF consumption, those in the highest quartile had a significantly increased risk of CD (HR, 1.70; 95% CI, 1.23-2.35; Ptrend = .0008). Among different UPF subgroups, ultra-processed breads and breakfast foods; frozen or shelf-stable ready-to-eat/heat meals; and sauces, cheeses, spreads, and gravies showed the strongest positive associations with CD risk (HR per 1 standard deviation increase in intake, 1.18 [95% CI, 1.07-1.29], 1.11 [95% CI, 1.01-1.22], and 1.14 [95% CI, 1.02-1.27], respectively). There was no consistent association between UPF intake and UC risk. CONCLUSIONS: Higher UPF intake was associated with an increased risk of incident CD. Further studies are needed to identify specific contributory dietary components.

Changes in dairy product consumption and risk of type 2 diabetes: results from 3 large prospective cohorts of US men and women.

BACKGROUND: Whether changes in dairy product consumption are related to subsequent risk of type 2 diabetes (T2D) remains unknown. OBJECTIVE: We evaluated the association of long-term changes in dairy product consumption with subsequent risk of T2D among US men and women. METHODS: We followed up 34,224 men in the Health Professionals Follow-Up Study (1986-2012), 76,531 women in the Nurses' Health Study (1986-2012), and 81,597 women in the Nurses' Health Study II (1991-2013). Changes in dairy consumption were calculated from consecutive quadrennial FFQs. Multivariable Cox proportional regression models were used to calculate HRs for T2D associated with changes in dairy product consumption. Results of the 3 cohorts were pooled using an inverse variance-weighted, fixed-effect meta-analysis. RESULTS: During 2,783,210 person-years, we documented 11,906 incident T2D cases. After adjustment for initial and changes in diet and lifestyle covariates, decreasing total dairy intake by >1.0 serving/d over a 4-y period was associated with an 11% (95% CI: 3%, 19%) higher risk of T2D in the subsequent 4 y compared with maintaining a relatively stable consumption (i.e., change in intake of ±1.0 serving/wk). Increasing yogurt consumption by >0.5 serving/d was associated with an 11% (95% CI: 4%, 18%) lower T2D risk, whereas increasing cheese consumption by >0.5 serving/d was associated with a 9% (95% CI: 2%, 16%) higher risk compared with maintaining stable intakes. Substituting 1 serving/d of yogurt or reduced-fat milk for cheese was associated with a 16% (95% CI: 10%, 22%) or 12% (95% CI: 8%, 16%) lower T2D risk, respectively. CONCLUSIONS: Increasing yogurt consumption was associated with a moderately lower risk of T2D, whereas increasing cheese consumption was associated with a moderately higher risk among US men and women. Our study suggests that substituting yogurt or reduced-fat milk for cheese is associated with a lower risk of T2D.