Sugar-Sweetened Beverages, Artificially Sweetened Beverages, and Breast Cancer Risk: Results From 2 Prospective US Cohorts

Artificially sweetened beverages consumption and risk of obesity-related cancers: a wide-angled Mendelian randomization study

Background

The impact of artificially sweetened beverages (ASBs) consumption on obesity-related cancers (ORCs) risk remains controversial. To address this challenging issue, this study employed wide-angle mendelian randomization (MR) analyses to explore the genetic causality between ASB consumption and the risk of ORCs, thereby effectively minimizing the impact of external confounders.

Methods

We conducted a suite of analyses encompassing univariable, multivariable, and two-step MR to evaluate causal associations between ASB consumption (samples = 85,852) and risk of ORCs (total samples = 2,974,770) using summary statistics from genome-wide association studies (GWAS). Total, direct, and intermediary effects were derived by performing inverse-variance weighted (IVW), MR-Egger, weighted mode, weighted median, and lasso method. Additionally, we performed an extensive range of sensitivity analyses to counteract the potential effects of confounders, heterogeneity, and pleiotropy, enhancing the robustness and reliability of the findings.

Results

Genetically predicted ASB consumption was positively associated with the risk of colorectal cancer (CRC, p = 0.011; OR: 6.879; 95% CI: 1.551, 30.512 by IVW) and breast cancer (p = 0.022; OR: 3.881; 95% CI: 2.023, 9.776 by IVW). Multivariable analysis yielded similar results. The results of the two-step MR unveiled that body mass index (BMI) assumes a pivotal role in mediating the association between ASB consumption and CRC risk (intermediary effect = 0.068, p = 0.024).

Conclusion

No causal connection exists between ASB consumption and the majority of ORCs, in addition to CRC and breast cancer. Additionally, our findings suggest that BMI might be a potential mediator in the association between ASB consumption and CRC.

Sugar-Sweetened Beverages Consumption and Breast Cancer in Premenopausal and Postmenopausal Women

BACKGROUND

The consumption of sugar-sweetened beverages (SSB), of which Mexico is a large consumer, has been associated with the risk of breast cancer. We assessed the association between SSBs consumption and breast cancer risk in pre- and postmenopausal women.

METHODS

We performed a multicenter population-based case-control study in Mexico City, Monterrey, and Veracruz. We recruited 1,000 cases and 1,074 controls; all participants were pre- or postmenopausal women between 35 and 69 years of age. Diet before symptoms onset was assessed using a food frequency questionnaire. We conducted a multivariable-adjusted conditional logistic regression analysis stratified by menopausal status.

RESULTS

For premenopausal women, after adjusting for matching characteristics, total energy intake and all potential confounders, the odds of having breast cancer in women who drank one or more SSBs servings per day showed 1.78 times the odds of those who drank one or fewer SSBs servings per month [OR = 1.78; 95% confidence interval (CI), 1.06-3.01]. For postmenopausal women, the corresponding model was not statistically significant (OR = 1.38, 95% CI, 0.84-2.25). We also observed higher consumption of SSBs among pre- than in postmenopausal women (23.3% and 17.4%, respectively among controls in the highest consumption category (≥1 per day).

CONCLUSIONS

Our results suggest that SSBs consumption increases the risk of developing breast cancer, particularly in premenopausal women.

IMPACT

Given the consumption of SSBs, of which Mexico is a large consumer, these results can support public policies to discourage the consumption of SSBs.

Perspectives on recent reviews of aspartame cancer epidemiology

Aspartame is a dipeptide non-sugar sweetener that was first marketed in the US in carbonated beverages in 1983, before gaining prominence globally. The Joint Food and Agriculture Organization of the United Nations (FAO)/World Health Organization (WHO) Expert Committee on Food Additives (JECFA) and the WHO International Agency for Research on Cancer (IARC) completed evaluations of aspartame and cancer in July 2023. JECFA reaffirmed the safety of aspartame, stating that epidemiology evidence is "not convincing," and that there are no consistent associations between aspartame and cancer (JECFA/IARC, 2023; JECFA, 2023). JECFA also noted "reverse causality, chance, bias and confounding by socioeconomic or lifestyle factors, or consumption of other dietary components, could not be completely ruled out" in relevant epidemiology studies (JECFA/IARC, 2023). In contrast, IARC stated that there are three "high quality" studies on liver cancer (Riboli, 2023), but that the evidence is limited because "chance, bias or confounding could not be ruled out as an explanation for the positive findings" (JECFA/IARC, 2023). IARC does not provide an explanation as to how these studies can be both high quality and have these weaknesses, most notably potential exposure misclassification, or how inconsistent associations from studies with these weaknesses constitute limited evidence. Further, when IARC concludes an agent has limited or inadequate human evidence (and no sufficient animal or strong mechanistic evidence), it classifies that agent as either Group 2B, a possible human carcinogen, or Group 3, not classifiable as to its carcinogenicity. Ultimately, the interpretations of Group 2B and Group 3 classifications are intended to be similar. However, a Group 2B designation may make it appear to scientists and non-scientists alike that the evidence is pointing in the direction of causality. This can lead to unnecessary confusion with respect to the evidence, as well as a perception of a disagreement within WHO regarding aspartame. This apparent contradiction could have been avoided by assigning the IARC classification most consistent with the conclusion that the human evidence for cancer is inadequate: Group 3.

Pro-Vegetarian Food Patterns and Cancer Risk among Italians from the Moli-Sani Study Cohort

Besides the Mediterranean diet, there is a paucity of studies examining plant-based diets in relation to cancer outcomes in Mediterranean populations. We analyzed 22,081 apparently cancer-free participants (mean age 55 ± 12 year) from the Moli-sani study (enrollment period 2005-2010; Italy). A general pro-vegetarian food pattern was computed by assigning positive or negative scores to plant- or animal-derived foods, respectively from a 188-item FFQ. A priori healthful or unhealthful pro-vegetarian food patterns distinguished between healthy plant foods (e.g., fruits, vegetables) and less-healthy plant foods (e.g., fruit juices, refined grains). Cancer incidence was defined as the earliest diagnosis of cancer from hospital discharge records over a median follow-up of 12.9 years. In multivariable-adjusted analyses, a general pro-vegetarian food pattern was associated with a lower rate of cancer incidence (HR = 0.85; 95%CI 0.75-0.97 for Q5 vs. Q1); no association was observed between the healthful or unhealthful pro-vegetarian food patterns and overall cancer incidence. A healthful pro-vegetarian pattern, however, was inversely associated with digestive cancer (HR = 0.76; 95%CI 0.58-0.99 for Q5 vs. Q1), while the unhealthful pro-vegetarian pattern was directly linked to respiratory cancer (HR = 1.68; 95%CI 1.06-2.68 for Q5 vs. Q1). Our findings in a Mediterranean population support the hypothesis that some, but not all pro-vegetarian diets, might prevent some cancers.

Associations between Knowledge of Health Risks and Sugar-Sweetened Beverage Intake among US Adolescents

BACKGROUND

Sugar-sweetened beverage (SSB) intake is associated with adverse health outcomes.

OBJECTIVE

We examined associations between the knowledge of health risks related to SSB and SSB intake among adolescents.

DESIGN

A cross-sectional study using 2021 YouthStyles survey data.

PARTICIPANTS/SETTINGS

831 US adolescents (12-17 years old).

MAIN OUTCOME MEASURES

The outcome variable was SSB intake (none, 1-6 times/week, and ≥1 time/day). Exposure variables were knowledge of seven SSB-related health risks.

STATISTICAL ANALYSES PERFORMED

Seven multinomial regressions were used to estimate adjusted odds ratios (AOR) for drinking SSB, according to knowledge of SSB-related health risks and after controlling for sociodemographics.

RESULTS

Overall, 29% of adolescents consumed SSB ≥1 time/day. Although most adolescents identified cavities (75.4%), weight gain (74.6%), and diabetes (69.7%) as being related to drinking SSB, fewer adolescents identified related conditions such as high blood pressure (31.7%), high cholesterol (25.8%), heart disease (24.6%), and some cancers (18.0%). Compared to non-SSB consumers, drinking SSB ≥1 time/day was significantly higher among adolescents who lacked knowledge of associations between SSB intake and weight gain (AOR = 2.0), heart disease (AOR = 1.9), or some cancers (AOR = 2.3) after controlling for covariates.

CONCLUSIONS

Among US adolescents, knowledge of SSB-related health risks varied by condition, ranging from 18% (some cancers) to 75% (cavities and weight gain). There were increased odds of drinking SSB among those unaware that weight gain, heart disease, and some cancers are associated with SSB intake. Intervention could evaluate whether increasing certain types of knowledge may influence youth SSB intake.

Association of soft drinks and 100% fruit juice consumption with risk of cancer: a systematic review and dose-response meta-analysis of prospective cohort studies

BACKGROUND

Studies of the associations between soft drinks and the risk of cancer showed inconsistent results. No previous published systematic reviews and meta-analysis has investigated a dose-response association between exposure dose and cancer risk or assessed the certainty of currently available evidence. Therefore, we aim to demonstrate the associations and assessed the certainty of the evidence to show our confidence in the associations.

METHODS

We searched Embase, PubMed, Web of Science, and the Cochrane Library from inception to Jun 2022, to include relevant prospective cohort studies. We used a restricted cubic spline model to conduct a dose-response meta-analysis and calculated the absolute effect estimates to present the results. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess the certainty of the evidence.

RESULTS

Forty-two articles including on 37 cohorts enrolled 4,518,547 participants were included. With low certainty evidence, increased consumption of sugar-sweetened beverages (SSBs) per 250 mL/day was significantly associated with a 17% greater risk of breast cancer, a 10% greater risk of colorectal cancer, a 30% greater risk of biliary tract cancer, and a 10% greater risk of prostate cancer; increased consumption of artificially sweetened beverages (ASBs)re per 250 mL/day was significantly associated with a 16% greater risk of leukemia; increased consumption of 100% fruit juice per 250 mL/day was significantly associated with a 31% greater risk of overall cancer, 22% greater risk of melanoma, 2% greater risk of squamous cell carcinoma, and 29% greater risk of thyroid cancer. The associations with other specific cancer were no significant. We found linear dose-response associations between consumption of SSBs and the risk of breast and kidney cancer, and between consumption of ASBs and 100% fruit juices and the risk of pancreatic cancer.

CONCLUSIONS

An increment in consumption of SSBs of 250 mL/day was positively associated with increased risk of breast, colorectal, and biliary tract cancer. Fruit juices consumption was also positively associated with the risk of overall cancer, thyroid cancer, and melanoma. The magnitude of absolute effects, however, was small and mainly based on low or very low certainty of evidence. The association of ASBs consumption with specific cancer risk was uncertain.

TRIAL REGISTRATION

PROSPERO: CRD42020152223.

Non-sugar sweeteners and cancer: Toxicological and epidemiological evidence

Several toxicological and epidemiological studies were published during the last five decades on non-sugar sweeteners (NSS) and cancer. Despite the large amount of research, the issue still continues to be of interest. In this review, we provided a comprehensive quantitative review of the toxicological and epidemiological evidence on the possible relation between NSS and cancer. The toxicological section includes the evaluation of genotoxicity and carcinogenicity data for acesulfame K, advantame, aspartame, cyclamates, saccharin, steviol glycosides and sucralose. The epidemiological section includes the results of a systematic search of cohort and case-control studies. The majority of the 22 cohort studies and 46 case-control studies showed no associations. Some risks for bladder, pancreas and hematopoietic cancers found in a few studies were not confirmed in other studies. Based on the review of both the experimental data on genotoxicity or carcinogenicity of the specific NSS evaluated, and the epidemiological studies it can be concluded that there is no evidence of cancer risk associated to NSS consumption.

Association between Consumption of Artificial Sweeteners and Breast Cancer Risk: A Systematic Review and Meta-Analysis of Observational Studies

This study intends to conduct a meta-analysis based on existing research results to further investigate their relationship between artificial sweetener exposure and breast cancer risk. An electronic database literature search was performed up to July 2022, using PubMed, Web of Science, Ovid and Scopus. The relationship between artificial sweetener exposure and breast cancer (BC) incidence was evaluated by odds ratio (OR) and 95% confidence interval (CI). Among the five studies (two case-control studies and three cohort studies) that met the inclusion criteria, 314,056 participants were recruited in the cohort study, 4,043 cancer cases and 3,910 controls were recruited in the case-control study. It was found that exposure of artificial sweeteners was not related to the risk of BC (OR = 0.98, 95% CI = [0.94-1.03]). Subgroup analysis showed that compared with the non-exposure/very-low-dose group, the exposure to low, medium and high doses of artificial sweeteners were not associated with the risk of BC, which were OR = 1.01, 95% CI = [0.95-1.07], OR = 0.98, 95% CI = [0.93-1.02], OR = 0.88, 95% CI = [0.74-1.06], respectively. This study confirmed that there was no relationship between the exposure of artificial sweeteners and the incidence of BC.

Insulinemic potential of diet and risk of total and subtypes of breast cancer among US females

BACKGROUND

Insulin resistance and hyperinsulinemia play important roles in the progression of multiple chronic disease and conditions. Diet modulates insulin response; however, evidence is limited regarding whether diets with higher insulinemic potential increase the risk of invasive breast cancer.

OBJECTIVES

We aimed to prospectively evaluate the association between a food-based empirical dietary index for hyperinsulinemia (EDIH) and the incidence of invasive breast cancer.

METHODS

We prospectively followed 76,686 women from the Nurses' Health Study (NHS; 1984-2016) and 93,287 women from the Nurses' Health Study II (NHSII; 1991-2017). Diet was assessed by food-frequency questionnaires every 4 y. The insulinemic potential of diet was evaluated using the previously established EDIH based on circulating C-peptide concentrations. Higher scores indicate higher insulinemic potential of the diet. Covariates included reproductive, hormonal, and anthropometric factors (height and BMI at age 18 y); race; socioeconomic status; total alcohol intake; total caloric intake; and physical activity.

RESULTS

During 4,216,106 person-years of follow-up, we documented 10,602 breast cancer cases (6689 NHS, 3913 NHSII). In the pooled multivariable-adjusted analyses, women in the highest, compared with the lowest, EDIH quintile (Q) were at higher breast cancer risk (HRQ5 vs. Q1 = 1.15; 95% CI: 1.07, 1.24; P-trend < 0.01). Although heterogeneity by estrogen receptor (ER) status was nonsignificant, the strongest association between EDIH and breast cancer was observed for ER-negative tumors (HRQ5 vs. Q1 = 1.21; 95% CI: 1.00, 1.46; P-trend = 0.02). Among tumor molecular subtypes, the strongest associations were observed for human epidermal growth factor receptor 2 (HER2)-enriched tumors (HRQ5 vs. Q1 = 1.62; 95% CI: 1.01, 2.61; P-trend = 0.02).

CONCLUSIONS

A dietary pattern contributing to hyperinsulinemia and insulin resistance was associated with greater breast cancer risk, especially ER-negative and HER2-enriched tumors. Our findings suggest that dietary modifications to reduce insulinemic potential may reduce the risk of breast cancer.

Artificially Sweetened Beverage Consumption and Cancer Risk: A Comprehensive Dose-Response Meta-Analysis of Prospective Studies

The impact of artificially sweetened beverages (ASBs), alternatives to sugar-sweetened beverages, on cancer incidence remains controversial. We conducted a meta-analysis of prospective studies to assess the association of daily ASB intake with cancer risk. A systematic search was performed between January 1967 and September 2022. Risk ratios (RR) or hazard ratios (HR) were extracted and pooled. The Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach was used for the assessment of the certainty of evidence. The study was registered at PROSPERO (CRD42022312171). Overall, 14 articles with 17 cohorts were included. There was no significant association between daily ASB consumption and risk of overall cancer (highest versus lowest category: n = 17, RR = 1.03, 95% CI: 0.96-1.11, p = 0.407). For site-specific cancer analysis, the risk of non-lymphoid leukemia was elevated with high ASB intake (n = 3, RR = 1.35, 95% CI: 1.03-1.77, p = 0.030), while risk of colorectal cancer was decreased (n = 3, RR = 0.78, 95% CI: 0.62-0.99, p = 0.037). Dose-response analysis indicated a positive linear association between ASB intake and the risk of leukemia (p_-linear = 0.027). The risk increased by 15% per one serving (355 mL) daily ASB intake increment (RR = 1.15, 95% CI: 1.02-1.30). In conclusion, ASB consumption might be positively associated with the risk of leukemia and negatively associated with the risk of colorectal cancer.

Can Artificial Sweeteners Increase the Risk of Cancer Incidence and Mortality: Evidence from Prospective Studies

Cancer has become a major challenge in the global disease burden. Artificial sweeteners are a class of chemical compounds that are used as food and beverage addition agent to replace sugar. However, the health effects of consuming artificial sweeteners are still unclear. This meta-analysis was performed to evaluate the role of artificial sweeteners on cancer. The databases PubMed, Cochrane Library, MEDLINE, Web of Science and EMBASE were searched up until July 2022. A Newcastle−Ottawa scale (NOS) was used to estimate the study quality. A total of 25 observational studies were included with a total of 3,739,775 subjects. The intake of artificial sweeteners had no apparent association with overall cancer incidence and mortality. However, in Europe, artificial sweeteners’ intake could increase the risk of cancer incidence (HR/RR = 1.07, 95% CI = [1.02, 1.12], I2 = 25.8%, P = 0.223), which appears to be related to a shift in nutritional behaviors in the countries. Significant results were also observed in subgroups with aspartame and a mixed intake of artificial sweeteners. Moreover, higher risk was observed for artificial sweeteners intake in all-cause mortality (HR/RR =1.13, 95% CI = [1.03, 1.25], I2 = 79.7%, p < 0.001) and a J-shaped association between them was found. More data from well-conducted studies and clinical trials are required.