Dietary Insulinemic Potential and Risk of Total and Cause-Specific Mortality in the Nurses' Health Study and the Health Professionals Follow-up Study

Associations of dietary patterns with kidney cancer risk, kidney cancer-specific mortality and all-cause mortality among postmenopausal women

BACKGROUND

The empirical dietary index for hyperinsulinemia (EDIH) and empirical dietary inflammatory pattern (EDIP) are novel measures of dietary quality associated with insulin hypersecretion or chronic inflammation, respectively, whereas the Healthy Eating Index (HEI-2015) measures adherence to the Dietary Guidelines for Americans (DGA). We evaluated associations of EDIH, EDIP and HEI-2015 on the risk of both kidney cancer development and mortality.

METHODS

We calculated the dietary scores from baseline food frequency questionnaires among 115,830 participants aged 50-79 years in the Women's Health Initiative. Multivariable-adjusted Cox regression was used to estimate hazard ratios (HR) and 95% confidence intervals (95%CI) for kidney cancer risk, kidney cancer-specific mortality and all-cause mortality, per 1-standard deviation increment in dietary pattern scores.

RESULTS

Higher EDIH was associated with greater risk of kidney cancer development [HR, 1.12; 95%CI, (1.01,1.23)], kidney cancer-specific death [1.22(0.99,1.48)], and all-cause mortality, [1.05(1.02,1.08)]. Higher HEI-2015 was associated with lower risk of kidney cancer development, [0.85(0.77, 0.94)], kidney cancer-specific death, [0.84(0.69,1.03)] and all-cause mortality, [0.97(0.95,1.00)]. However, EDIP was not significantly associated with outcomes. Associations did not differ by BMI categories.

CONCLUSIONS

Low-insulinemic dietary patterns and higher quality diets, are worthy of testing in dietary pattern intervention trials for kidney cancer prevention and improved survivorship.

A Comparative Study of Healthy Dietary Patterns for Incident and Fatal Digestive System Cancer

INTRODUCTION

We examined multiple dietary patterns in relation to total digestive system cancer (DSC) incidence and death.

METHODS

A total of 213,038 health professionals from the Health Professionals Follow-up Study (1986-2016), the Nurses' Health Study (1986-2018), and the Nurses' Health Study II (1991-2017) with no cancer diagnosis at baseline were analyzed. DSC incidence and death were estimated using time-varying Cox proportional hazards regression models.

RESULTS

During up to 32 years of follow-up, 5,724 DSC cases accrued. Adherence to 8 healthy diet patterns was associated with a 7%-13% lower risk of DSC, particularly for digestive tract cancers. An inverse association with gastrointestinal tract cancer was also shown for all pattern scores except Alternate Mediterranean Diet and the healthful Plant-based Diet Index, with hazard ratios between 0.84 and 0.89. Inverse associations were shown for the reversed empirical dietary index for hyperinsulinemia (hazard ratio for 90th vs 10th percentile 0.64, 95% confidence interval [CI] 0.47-0.87) and the empirical dietary index associated with lower inflammation (rEDIP) (0.53, 95% CI 0.39-0.72) for stomach cancer, and for the rEDIP (0.58, 95% CI 0.37-0.92) for small intestine cancer. Among accessory cancers, the Alternate Healthy Eating Index-2010, alternate Mediterranean diet, and diabetes risk reduction diet were associated with a 43%-51% lower risk of liver cancer. The reversed empirical dietary index for hyperinsulinemia, rEDIP, and the Alternate Healthy Eating Index-2010 were inversely associated with the risk of fatal DSC.

DISCUSSION

Adherence to healthy diets was associated with a lower risk of incident and fatal DSC, although the magnitude of the association varied slightly among the patterns.

Dietary Guidance for Cardiovascular Health: Consensus and Controversies

Healthy diet, regular exercise and smoking cessation comprise the 'golden triad' of primary prevention of cardiovascular disease (CVD) [...].

Insulin and aging - a disappointing relationship

Experimental studies in animal models of aging such as nematodes, fruit flies or mice have observed that decreased levels of insulin or insulin signaling promotes longevity. In humans, hyperinsulinemia and concomitant insulin resistance are associated with an elevated risk of age-related diseases suggestive of a shortened healthspan. Age-related disorders include neurodegenerative diseases, hypertension, cardiovascular disease, and type 2 diabetes. High ambient insulin concentrations promote increased lipogenesis and fat storage, heightened protein synthesis and accumulation of non-functional polypeptides due to limited turnover capacity. Moreover, there is impaired autophagy activity, and less endothelial NO synthase activity. These changes are associated with mitochondrial dysfunction and oxidative stress. The cellular stress induced by anabolic activity of insulin initiates an adaptive response aiming at maintaining homeostasis, characterized by activation of the transcription factor Nrf2, of AMP activated kinase, and an unfolded protein response. This protective response is more potent in the long-lived human species than in short-lived models of aging research resulting in a stronger pro-aging impact of insulin in nematodes and fruit flies. In humans, resistance to insulin-induced cell stress decreases with age, because of an increase of insulin and insulin resistance levels but less Nrf2 activation. These detrimental changes might be contained by adopting a lifestyle that promotes low insulin/insulin resistance levels and enhances an adaptive response to cellular stress, as observed with dietary restriction or exercise.

The Association of Empirical Dietary Index for Hyperinsulinemia with the Risk of Cancer and Cancer Mortality: A Meta-analysis of Observational Studies

This meta-analysis aimed to assess the association between the empirical dietary index for hyperinsulinemia (EDIH) and cancer mortality risk. We performed a comprehensive search across the online literature up to November 2022 databases. Then, hazard ratio (H.R.) and 95% confidence intervals (CI) were extracted. A total of 14 and seven cohort studies that reported H.R. for the risk of cancer incidence and cancer mortality respectively were included. The pooled H.R. (95% CI) of the association between EDIH and cancer incidence was 1.13 (1.05-1.23) in overall meta-analyses, 1.15 (1.08-1.22) in female subgroups, 1.27 (1.14-1.41) in digestive cancer subgroups, and 1.15 (1.07-1.24) in breast cancer subgroups. Also, the pooled H.R. (95% CI) of the association between EDIH and incidence of cancer mortality was 1.19 (1.13-1.26) in overall meta-analyses, 1.23 (1.13-1.34) in males, 1.18(1.10-1.28) in females, and 1.20 (1.13-1.27) in studies conducted on all cancers as an outcome. Our findings revealed that a higher EDIH was significantly associated with an increased risk of cancer incidence, particularly in females, digestive cancers, and breast cancer. Also, a higher EDIH score was related to a higher risk of cancer mortality overall in both male and female subgroups and with all cancers.

Hyperinsulinemic and Pro-Inflammatory Dietary Patterns and Metabolomic Profiles Are Associated with Increased Risk of Total and Site-Specific Cancers among Postmenopausal Women

We evaluated associations of the Empirical Dietary Index for Hyperinsulinemia (EDIH), Empirical Dietary Inflammatory Pattern (EDIP) and Healthy Eating Index (HEI2015) and their metabolomics profiles with the risk of total and site-specific cancers. We used baseline food frequency questionnaires to calculate dietary scores among 112,468 postmenopausal women in the Women's Health Initiative. We used multivariable-adjusted Cox regression to estimate hazard ratios (HR) and 95% confidence intervals for cancer risk estimation. Metabolomic profile scores were derived using elastic-net regression with leave-one-out cross validation. In over 17.8 years, 18,768 incident invasive cancers were adjudicated. Higher EDIH and EDIP scores were associated with greater total cancer risk, and higher HEI-2015 with lower risk: HRQ5vsQ1(95% CI): EDIH, 1.10 (1.04-1.15); EDIP, 1.08 (1.02-1.15); HEI-2015, 0.93 (0.89-0.98). The multivariable-adjusted incidence rate difference(Q5vsQ1) for total cancer was: +52 (EDIH), +41 (EDIP) and -49 (HEI-2015) per 100,000 person years. All three indices were associated with colorectal cancer, and EDIH and EDIP with endometrial and breast cancer risk. EDIH was further associated with luminal-B, ER-negative and triple negative breast cancer subtypes. Dietary patterns contributing to hyperinsulinemia and inflammation were associated with greater cancer risk, and higher overall dietary quality, with lower risk. The findings warrant the testing of these dietary patterns in clinical trials for cancer prevention among postmenopausal women.

Optimal dietary patterns for prevention of chronic disease

Multiple dietary patterns have been associated with different diseases; however, their comparability to improve overall health has yet to be determined. Here, in 205,852 healthcare professionals from three US cohorts followed for up to 32 years, we prospectively assessed two mechanism-based diets and six diets based on dietary recommendations in relation to major chronic disease, defined as a composite outcome of incident major cardiovascular disease (CVD), type 2 diabetes and cancer. We demonstrated that adherence to a healthy diet was generally associated with a lower risk of major chronic disease (hazard ratio (HR) comparing the 90th with the 10th percentile of dietary pattern scores = 0.58-0.80). Participants with low insulinemic (HR = 0.58, 95% confidence interval (CI) = 0.57, 0.60), low inflammatory (HR = 0.61, 95% CI = 0.60, 0.63) or diabetes risk-reducing (HR = 0.70, 95% CI = 0.69, 0.72) diet had the largest risk reduction for incident major CVD, type 2 diabetes and cancer as a composite and individually. Similar findings were observed across gender and diverse ethnic groups. Our results suggest that dietary patterns associated with markers of hyperinsulinemia and inflammation and diabetes development may inform on future dietary guidelines for chronic disease prevention.