Dietary glycemic index, glycemic load, and risk of breast cancer: meta-analysis of prospective cohort studies

Carbohydrate quality indices and lung cancer risk: a case-control study from Iran

Considering that carbohydrates play an important role in supplying the body with energy and exhibit diverse mechanisms that can either prevent or stimulate cancer, we hypothesize that the quality of carbohydrate intake may be associated with cancer risk, including lung cancer. This hospital-based case-control study was conducted on 135 newly diagnosed lung cancer patients, and 237 healthy age- and sex-matched hospitalized controls. We used a valid and reliable 148-item Food Frequency Questionnaire to collect the dietary intake of subjects. Multivariate logistic regression was used to estimate the association between carbohydrate quality indices and the odds of lung cancer. After adjustment for confounding variables, the high glycemic index appears to be an increased risk factor for lung cancer [odds ratio (OR) = 2.51, 95% confidence interval (CI): 1.28-4.91]. No statistically significant association was found between glycemic load and lung cancer (OR = 2.51, 95% CI: 0.98-6.43). In contrast, the carbohydrate quality index (OR = 0.23, 95% CI: 0.11-0.48) and low-carbohydrate diet score (OR = 0.17, 95% CI: 0.08-0.36), were associated with a decrease in the risk of lung cancer. In summary, our study showed that a high glycemic index is a risk factor for lung cancer, however carbohydrate quality index and low-carbohydrate diet score is a dietary approach to reduce the risk of lung cancer.

Dietary insulin indices and low-carbohydrate diet and the odds of colorectal cancer: a case-control study

BACKGROUND

Regarding the role of insulin and insulin-inducing dietary factors in some cancers' etiology, we hypothesized that the risk of colorectal cancer may be lessened by following a lower carbohydrate and insulinogenic diet. Therefore, we performed this study to explore the association between a low-carbohydrate diet and insulin indices and the odds of colorectal cancer.

METHOD

This hospital-based case-control study was conducted on 150 newly diagnosed colorectal cancer patients and 300 healthy age- and sex-matched hospitalized controls. A valid and reliable food frequency questionnaire was used to calculate the insulin indices and low-carbohydrate diet score. Multivariate logistic regression was used to estimate the association between insulin indices and low-carbohydrate diet and the odds of colorectal cancer.

RESULT

After adjusting for potential confounders, individuals in the highest tertile of insulin indices had a higher risk of colorectal cancer (OR insulin index  = 3.46; 95% CI, 2.00-5.96; OR insulin load  = 2; 95% CI, 1.17-3.41). No association was found between a low-carbohydrate diet and colorectal cancer (OR = 1.55; 95% CI, 0.85-2.84).

CONCLUSION

Current results demonstrated that a high insulinemic diet was associated with a higher risk of colorectal cancer.

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.

Dietary carbohydrate quality and risk of breast cancer among women

Background

A few studies have examined the relationship between carbohydrate quality index (CQI) and risk of breast cancer (BC) among women in Middle Eastern countries. We studied the associations between carbohydrate quality index and the risk of BC in overall and by menopausal status.

Methods

In this case-control study, dietary intake of 461 women with pathologically confirmed BC within the past year were examined. The same information were collected for 495 apparently healthy controls using a 168-item validated FFQ. Carbohydrate quality was determined by considering four criteria including: ratio of solid carbohydrates to total carbohydrates, dietary fiber intake, GI and the ratio of whole grains to total grains.

Results

Mean GI and GL of participants were totally 57.5 ± 7.2 and 245.7 ± 64.7, respectively. A trend toward significant association was seen between GI and odds of BC in the whole population; such that after stratifying analysis by menopausal status, premenopausal women in the highest quartile of GI were 1.85 times higher likely to have BC than those in the lowest quartile (95% CI: 1.12, 3.07, P = 0.01). We found that women with the greatest CQI had lower odds for BC, compared with those with the lowest CQI (0.63; 95% CI: 0.43–0.94, P = 0.03). This association was remained after stratifying analysis by menopausal status in premenopausal (0.55; 95% CI: 0.34–0.90, P = 0.04).

Conclusion

We found that GI was directly and CQI inversely associated with odds of BC. In order to determine the effects of dietary carbohydrate quality prospective cohort studies are needed.

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

BACKGROUND

Whether consumption of sugar-sweetened beverages (SSBs) or artificially sweetened beverages (ASBs) is associated with the risk of breast cancer is of public health interest.

OBJECTIVES

We sought to evaluate associations between consumption of SSBs and ASBs and risks of total and subtype-specific breast cancer.

METHODS

We followed 82,713 women from the Nurses' Health Study (1980 to 2016) and 93,085 women from the Nurses' Health Study II (1991 to 2017). Cumulatively averaged intakes of SSBs and ASBs from FFQs were tested for associations with incident breast cancer cases and subtypes using Cox regression models. We also evaluated the associations stratified by menopausal status, physical activity, BMI, and alcohol intake.

RESULTS

We documented 11,379 breast cancer cases during 4,655,153 person-years of follow-up. Consumption of SSBs or ASBs was not associated with total breast cancer risk: pooled HRs comparing extreme categories (≥1/day compared with <1/month) were 1.03 (95% CI, 0.95-1.12) and 0.96 (95% CI, 0.91-1.02), respectively. We observed a suggestive interaction by BMI using pooled data (P-interaction = 0.08), where a modestly higher risk of breast cancer with each serving per day increment of SSBs was found in lean women (HR, 1.06; 95% CI, 1.01-1.11) but not among overweight or obese women (HR, 1.00; 95% CI, 0.95-1.06). Moreover, in the pooled, fully adjusted analysis, compared to infrequent consumers (<1/month), those who consumed ≥1 serving of ASBs per day had a lower risk of luminal A breast tumors (HR, 0.90; 95% CI, 0.80-1.01; P-trend = 0.02).

CONCLUSIONS

Although no significant associations were observed overall, consumption of SSBs was associated with a slightly higher risk of breast cancer among lean women. This finding could have occurred by chance and needs confirmation. Our findings also suggest no substantial increase in the risk of breast cancer with consumption of ASBs.

Dietary Insulin Index and Insulin Load in Relation to Breast Cancer: Findings from a Case-Control Study

BACKGROUND

No data are available on the association between dietary insulin index (DII) and dietary insulin load (DIL) and the risk of breast cancer (BC).

PATIENTS AND METHODS

This hospital-based case-control study enrolled 150 newly diagnosed cases of BC and 150 age-matched controls. All cases were patients with pathologically confirmed BC, with no history of any type of other pathologically confirmed cancers. Controls were selected from visitors, relatives, and friends of non-cancer patients in other wards who had no family relationships with the cases. We assessed the dietary intakes of study participants using a validated 147-item semiquantitative food frequency questionnaire. DII and DIL were obtained from previously published data.

RESULTS

A significant positive association was found between DII and BC (odds ratio [OR], 1.82; 95% confidence interval [CI], 1.02-3.25), such that after considering energy intake and age, participants in the highest tertile of DII had 1.86 times greater risk of BC than those in the lowest tertile (OR, 1.86; 95% CI, 1.03-3.35). However, this association became non-significant after controlling for further potential risk factors (OR, 3.26; 95% CI, 0.9-11.7). Furthermore, we observed a significant positive association between DIL and BC (OR, 1.9; 95% CI, 1.06-3.40). The association remained significant even after controlling for age and energy intake. Further controlling for other potential confounders resulted in the disappearance of the association (OR, 3.06; 95% CI, 0.87-10.6).

CONCLUSION

Adherence to a diet with high DII and DIL was not associated with odds of BC after controlling for potential confounders.

Thrombospondin-4 mediates hyperglycemia- and TGF-beta-induced inflammation in breast cancer

Inflammation drives the growth of tumors and is an important predictor of cancer aggressiveness. CD68, a marker of tumor-associated macrophages (TAM), is routinely used to aid in prognosis and treatment choices for breast cancer patients. We report that thrombospondin-4 (TSP-4) mediates breast cancer inflammation and growth in mouse models in response to hyperglycemia and TGF-beta by increasing TAM infiltration and production of inflammatory signals in tumors. Analysis of breast cancers and noncancerous tissue specimens from hyperglycemic patients revealed that levels of TSP-4 and of macrophage marker CD68 are upregulated in diabetic tissues. TSP-4 was colocalized with macrophages in cancer tissues. Bone-marrow-derived macrophages (BMDM) responded to high glucose and TGF-beta by upregulating TSP-4 production and expression, as well as the expression of inflammatory markers. We report a novel function for TSP-4 in breast cancer: regulation of TAM infiltration and inflammation. The results of our study provide new insights into regulation of cancer growth by hyperglycemia and TGF-beta and suggest TSP-4 as a potential therapeutic target.

Hyperglycemia-Induced miR-467 Drives Tumor Inflammation and Growth in Breast Cancer

The tumor microenvironment contains the parenchyma, blood vessels, and infiltrating immune cells, including tumor-associated macrophages (TAMs). TAMs affect the developing tumor and drive cancer inflammation. We used mouse models of hyperglycemia and cancer and specimens from hyperglycemic breast cancer (BC) patients to demonstrate that miR-467 mediates the effects of high blood glucose on cancer inflammation and growth. Hyperglycemic patients have a higher risk of developing breast cancer. We have identified a novel miRNA-dependent pathway activated by hyperglycemia that promotes BC angiogenesis and inflammation supporting BC growth. miR-467 is upregulated in endothelial cells (EC), macrophages, BC cells, and in BC tumors. A target of miR-467, thrombospondin-1 (TSP-1), inhibits angiogenesis and promotes resolution of inflammation. Systemic injections of a miR-467 antagonist in mouse models of hyperglycemia resulted in decreased BC growth (p < 0.001). Tumors from hyperglycemic mice had a two-fold increase in macrophage accumulation compared to normoglycemic controls (p < 0.001), and TAM infiltration was prevented by the miR-467 antagonist (p < 0.001). BC specimens from hyperglycemic patients had increased miR-467 levels, increased angiogenesis, decreased levels of TSP-1, and increased TAM infiltration in malignant breast tissue in hyperglycemic vs. normoglycemic patients (2.17-fold, p = 0.002) and even in normal breast tissue from hyperglycemic patients (2.18-fold increase, p = 0.04). In malignant BC tissue, miR-467 levels were upregulated 258-fold in hyperglycemic patients compared to normoglycemic patients (p < 0.001) and increased 56-fold in adjacent normal tissue (p = 0.008). Our results suggest that miR-467 accelerates tumor growth by inducing angiogenesis and promoting the recruitment of TAMs to drive hyperglycemia-induced cancer inflammation.

Effects of High-Fructose Diet vs. Teklad Diet in the MNU-Induced Rat Mammary Cancer Model: Altered Tumorigenesis, Metabolomics and Tumor RNA Expression

Epidemiology, clinical and experimental animal studies suggest high fructose diets are detrimental to metabolic status and may contribute to tumor development. This due to increased obesity and metabolic syndrome, known risk factors for many types of cancer. We compared tumor development in N-methyl-N-nitrosourea (MNU)-treated rats fed either a high (60%)-fructose diet (HFD) or a standard diet (SD). Female Sprague-Dawley rats at 43 days of age (DOA) were fed a SD or HFD followed by administration of MNU at 50 DOA. Rats were palpated weekly and sacrificed at 190 DOA. MNU-treated rats on HFD exhibited decreased tumor latency and roughly a two-fold increase in tumor multiplicity. RNA-Seq on frozen tumors (SD vs. HFD rats) showed altered expression of approximately 10% of genes (P < 0.05). When examined by Ingenuity Pathway Analysis, multiple highly significant pathways were identified including A) mechanisms of cancer, B) Wnt pathway, C) immune response (e.g., "Th1 and Th2 activation" and "antigen presentation") and D) LXR/RXR nuclear receptor. These generalized pathways were indirectly confirmed by alterations of various interrelated disease pathways (epithelial cancers, T cell numbers and apoptosis). In a second study, serum was collected from rats on the HFD or SD pre-MNU and at the time of sacrifice. Metabolomics revealed that the HFD yielded: A) increased levels of fructose, B) increases of various monoglycerols, C) reduced levels of various diacylglycerols and oxygenated inflammatory lipids (9 and 13 HODE and 12,13 DHOME) and D) increased levels of secondary bile acids (hyodeoxycholate and 6-oxolithocholate), which may reflect microbiome changes. These metabolomic changes, which are distinct from those on a high-fat diet, may prove relevant when examining individuals who consume higher levels of fructose.

Dietary glycemic index, glycemic load, and chronic disease: an umbrella review of meta-analyses of prospective cohort studies

We aimed to present a comprehensive review of the association of dietary glycemic index (GI) and load (GL) with the risk of chronic disease. Published meta-analyses of prospective observational studies evaluating the association of dietary GI and GL with risk of chronic disease were identified by a search in PubMed and Scopus to November, 2020. Summary relative risks (SRRs) were recalculated using random-effects models. The certainty of evidence was rated by the GRADE approach. Eighteen meta-analyses of prospective cohort studies, reporting 19 SRRs for dietary GI and 17 SRRs for dietary GL were identified. There was a positive association between dietary GI and the risk of type 2 diabetes, coronary heart disease, and colorectal, breast, and bladder cancers, as well as between dietary GL and the risk of coronary heart disease, type 2 diabetes, and stroke. With regard to cancers at other sites, there was no significant association. The certainty of evidence ranged from very low to low. Although by GRADE classification no associations were rated stronger than low, they were classified as one grade higher when the NutriGrade system was used. Further research is needed to add evidence for the relation of dietary GI and GL with cancer risk.

Investigating the associations of glycemic load and glycemic index with lung cancer risk in the Southern Community Cohort Study

PURPOSE

Diets with a high glycemic load (GL) or glycemic index (GI) may increase cancer risk. Findings from prior studies on the relationship between GL, GI, and lung cancer risk are inconsistent. We investigated this relationship in a large prospective cohort.

METHODS

We analyzed data from the Southern Community Cohort Study, a prospective cohort that includes diverse racial groups predominantly low-income adults aged 40-79 in 12 southeastern states of the USA. We estimated dietary GL and GI values using data collected from food frequency questionnaires at baseline. Dietary GL and GI were energy adjusted by residual method and categorized into sex-specific quintiles. Cox proportional hazard regression was used to assess the associations between dietary GL, GI, and lung cancer risk. We further performed stratified analyses by various factors.

RESULTS

Intakes of individual food items or food groups that commonly contribute to GL were similar between blacks and whites in the cohort. After excluding the first two years of follow-up, 947 incident lung cancers were ascertained among 55,068 participants. Neither dietary GL nor GI was significantly associated with incident lung cancer risk in the overall population (GL: Q5 vs. Q1, HR = 0.88, 95% CI 0.72-1.07, p_trend = 0.29; GI: Q5 vs. Q1, HR = 1.06, 95% CI 0.86-1.30, p_trend = 0.71), nor in subgroups of populations (p_trend > 0.05), in multivariable-adjusted analyses.

CONCLUSION

Dietary GL and GI were not independently associated with incident lung cancer risk in a large understudied population.

Dietary Carbohydrate Constituents Related to Gut Dysbiosis and Health

Recent studies report that microbiota in the human intestine play an important role in host health and that both long- and short-term diets influence gut microbiota. These findings have fueled interest in the potential of food to promote health by shaping the intestinal microbiota. Despite the fact that large populations in Asia consume high quantities of carbohydrates, such diets have been ignored in comparison to the attention received by Western diets containing high quantities of fat and animal protein. We gathered data that suggest an association between imbalanced high-carbohydrate intake and gut microbiota and host health. In this review, we identify not only the effect of total carbohydrates on the intestinal microbiota specifically and the health of their hosts in general, but also how specific types of carbohydrates influence both factors.

Dietary fibre content in ethnic and unconventional vegetables and fruits growing in Bangladesh

Dietary fibres are known to provide health benefit and protect against degenerative chronic diseases. Thus, the present study reports the total dietary fibre (TDF) content of sixty-nine selected ethnic and unconventional vegetables and fruits growing in Bangladesh. The samples were collected from different locations of Bangladesh and mixed together to ensure sample representativeness. Dietary fibre assay kit according to the AOAC method was utilized for the analysis of TDF in selected vegetables and fruits. In the ethnic varieties, the TDF content ranged from 1.02 ± 0.16 to 7.16 ± 0.16 g for leafy (LV), 0.18 ± 0.01 to 6.71 ± 0.49 g for non-leafy vegetables (NLV) and 1.21 ± 0.12 to 5.29 ± 0.20 g for fruits per 100 g edible portion (EP).  In the unconventional items, it arrayed from 3.08 ± 0.34 g to 7.75 ± 0.13 g for LV and 1.02 ± 0.06 to 8.82 ± 0.40 g for NLV per 100 g EP. Among the analysed samples, the highest and lowest content of TDF was found in Orohordal and Mairabokong, respectively. The unconventional vegetables contained much higher content of TDF than the ethnics and the commonly consumed similar varieties. Data on TDF content in underutilized vegetables and fruits of Bangladesh is sparse. Thus, the finding of this study would fill up the data gap in the existing food composition table of Bangladesh and also would aware the people to take vegetables and fruits rich in fibres.

Interrelationship between oxidative stress, DNA damage and cancer risk in diabetes (Type 2) in Riyadh, KSA

Type 2 Diabetes Mellitus (T2DM) is the most widely known type of disorder of the endocrine system marked by hyperglycemia resulting either due to deficiency of insulin and or resistance. Persistent hyperglycemia induces oxidative stress and is suggested to play a prominent role in the pathophysiology underlying T2DM. Besides, oxidative stress can result in DNA damage leading to high cancer risk. Current study aimed to evaluate status of oxidative damage, damage to DNA and cancer biomarkers in regard to increased glucose in T2DM patients and to correlate the glycemic state with cancer. A total of 150 subjects consisting of control (50) and T2DM patients (1 0 0) were enrolled. Additionally, three tertiles were created among the two groups based on levels of HbA1c (Tertile I = 5.37 ± 0.34, n = 50; Tertile II = 6.74 ± 0.20, n = 50; Tertile III = 9.21 ± 1.47, n = 50). Oxidative stress parameters including malondialedehyde (MDA) and antioxidant enzymes were measured. Damage to DNA was analyzed by measuring the levels of DNA damage adduct-8 hydroxy deoxy Guanosine (8-OHdG). To detect cancer resulting from oxidative stress, cancer biomarkers CEA, AFP, CA125, CA-15, CA19-9, prolactin were measured in these subjects. All measurements were analysed by SPSS software. Levels of MDA and antioxidant enzymes altered significantly in T2DM group at p < 0.001 and p < 0.05 level of significance. Significant DNA damage accompanied with elevated levels of CEA, CA19-9 and decreased CA125, AFP and prolactin were noted in T2DM group. CA 19-9 and CEA levels increased at p < 0.05, whereas levels of prolactin decreased significantly (p < 0.001) in T2DM group compared to control. Additionally the mean values of DNA damage adduct 8-OHdG differ significantly at P < 0.01 between the two groups. However, no significant correlation in oxidative stress parameter, antioxidant enzymes, DNA damage and neither with the highest tertile of HbA1c (>7.5%) was noted. Based on the results obtained in the present study, we conclude that there is considerable change in oxidative stress and DNA damage in T2DM patients. Hence, assumption that the oxidative stress could cause cancer in T2DM as a result of hyperglycemic state was not speculated in this study.

Nutrition in the Prevention of Breast Cancer: A Middle Eastern Perspective

This paper reviews the escalating burden of breast cancer (BC) in the Middle East (ME) and the prevalence of modifiable risk factors and underscores opportunities to promote the prevention of the disease. Similar to more developed countries, BC is the most frequent cancer among women in countries of the ME, accounting for one-third of total cancer cases and 24% of total cancer deaths. Average age at BC diagnosis appears to be a decade earlier in Middle Eastern countries compared to the Western countries, and its incidence is predicted to further increase. Although incidence rates of BC are still lower in Middle Eastern countries than Western ones, mortality rates are similar and at times even higher. It is estimated that 30% of BC cases are due to environmental and lifestyle factors, such as obesity and diet and hence can be preventable. The ME suffers from surging rates of obesity, with eight of its countries ranking among the highest worldwide in obesity prevalence among adults aged 18 and above. ME countries with the highest prevalence of obesity that are among the top 20 worldwide include United Arab Emirates (UAE), Lebanon, Egypt, Libya, Qatar, Saudi Arabia, Jordan, and Kuwait with rates ranging from 30% in UAE to 37% in Kuwait. In parallel, studies in the ME have consistently showed a shift in dietary intake whereby traditional diets, rich in fruits and vegetables, are progressively eroding and being replaced by westernized diets high in energy and fat. Accumulating evidence is reporting convincing association between consumption of such westernized diets and higher BC risk. Addressing these risk factors and studying their association with BC in terms of their nature and magnitude in Middle Eastern countries could provide the basis for intervention strategies to lower the risk and alleviate the burden of BC in these countries.

Glycemic Index, Glycemic Load and Cancer Risk: An Updated Meta-Analysis

Diets high in glycemic index (GI) and glycemic load (GL) have been related to an increased risk of selected cancers, but additional quantification is required. We updated a systematic review and meta-analysis published in 2015 to May 2019 to provide quantitative information on GI/GL and cancer risk. Relative risks (RR) and the corresponding 95 % confidence intervals (CI) for the highest versus the lowest categories of GI and GL were extracted from selected studies and pooled using random-effects models. Twenty reports (>22,000 cancer cases) have become available after January 2015, and 15 were added to the meta-analyses by cancer sites, which considered a total of 88 investigations. The five additional reports were reviewed, but not included in the meta-analyses, since data were inadequate to be pooled. For hormone-related cancers, summary RRs for the highest versus lowest GI and GL intakes were moderately increased. They ranged from 1.04 (breast) to 1.12 (endometrium) for GI and from 1.03 (prostate) to 1.22 (ovary) for GL, of borderline significance. High GI was associated with small increased risks of colorectal (summary RR for GI: 1.20, 95% CI, 1.07–1.34—GL: 1.09, 95% CI, 0.97–1.22, 19 studies), bladder (GI: 1.25, 95% CI, 1.11–1.41—GL: 1.10, 95% CI, 0.85–1.42, four studies) and kidney cancers (GI: 1.16, 95% CI, 1.02–1.32—GL: 1.14, 95% CI, 0.81–1.60, five studies). GL was not significantly related to those cancer sites. Stomach, prostate and lung cancers were not associated with GI and GL. The present analysis, based on an updated comprehensive evaluation of the epidemiological literature, indicates moderate unfavorable effects of high versus low GI on colorectal, and possibly bladder and kidney cancers, and a possible moderate positive association between GL and endometrial cancer.

Sugary drink consumption and risk of cancer: results from NutriNet-Santé prospective cohort

OBJECTIVE

To assess the associations between the consumption of sugary drinks (such as sugar sweetened beverages and 100% fruit juices), artificially sweetened beverages, and the risk of cancer.

DESIGN

Population based prospective cohort study.

SETTING AND PARTICIPANTS

Overall, 101 257 participants aged 18 and over (mean age 42.2, SD 14.4; median follow-up time 5.1 years) from the French NutriNet-Santé cohort (2009-2017) were included. Consumptions of sugary drinks and artificially sweetened beverages were assessed by using repeated 24 hour dietary records, which were designed to register participants' usual consumption for 3300 different food and beverage items.

MAIN OUTCOME MEASURES

Prospective associations between beverage consumption and the risk of overall, breast, prostate, and colorectal cancer were assessed by multi-adjusted Fine and Gray hazard models, accounting for competing risks. Subdistribution hazard ratios were computed.

RESULTS

The consumption of sugary drinks was significantly associated with the risk of overall cancer (n=2193 cases, subdistribution hazard ratio for a 100mL/d increase 1.18, 95% confidence interval 1.10 to 1.27, P<0.0001) and breast cancer (693, 1.22, 1.07 to 1.39, P=0.004). The consumption of artificially sweetened beverages was not associated with the risk of cancer. In specific subanalyses, the consumption of 100% fruit juice was significantly associated with the risk of overall cancer (2193, 1.12, 1.03 to 1.23, P=0.007).

CONCLUSIONS

In this large prospective study, the consumption of sugary drinks was positively associated with the risk of overall cancer and breast cancer. 100% fruit juices were also positively associated with the risk of overall cancer. These results need replication in other large scale prospective studies. They suggest that sugary drinks, which are widely consumed in Western countries, might represent a modifiable risk factor for cancer prevention.

STUDY REGISTRATION

ClinicalTrials.gov NCT03335644.

Thrombospondins and remodeling of the tumor microenvironment

Vascular remodeling defines cancer growth and aggressiveness. Although cancer cells produce pro-angiogenic signals, the fate of angiogenesis critically depends on the cancer microenvironment. Composition of the extracellular matrix (ECM) and tumor inflammation determine whether a cancer will remain dormant, will be recognized by the immune system and eliminated, or whether the tumor will develop and lead to the spread and metastasis of cancer cells. Thrombospondins (TSPs), a family of ECM proteins that has long been associated with the regulation of angiogenesis and cancer, regulate multiple physiological processes that determine cancer growth and spreading, from angiogenesis to inflammation, metabolic changes, and properties of ECM. Here, we sought to review publications that describe various functions of TSPs that link these proteins to regulation of cancer growth by modulating multiple physiological and pathological events that prevent or support tumor development. In addition to its direct effects on angiogenesis, TSPs have important roles in regulation of inflammation, immunity, ECM properties and composition, and glucose and insulin metabolism. Furthermore, TSPs have distinct roles as regulators of remodeling in tissues and tumors, such that the pathways activated by a single TSP can interact and influence each other. The complex nature of TSP interactions and functions, including their different cell- and tissue-specific effects, may lead to confusing results and controversial conclusions when taken out of the context of interdisciplinary and holistic approaches. However, studies of TSP functions and roles in different systems of the organism offer an integrative view of tumor remodeling and a potential for finding therapeutic targets that would modulate multiple complementary processes associated with cancer growth.

Dietary Glycemic Load, Glycemic Index, and Carbohydrate Intake on the Risk of Lung Cancer among Men and Women in Shanghai

To investigate the potential influence of dietary glycemic index, glycemic load, or carbohydrate intake and lung cancer risk in Shanghai. We prospectively investigated the associations among 130,858 participants in the Shanghai Women's and Men's Health Studies. Diet was assessed using validated food-frequency questionnaires. Lung cancer cases were ascertained through annual record linkage and every 2-3 years in-home visits. Cox proportional hazard regression model was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). After excluding the first 2 years of observation, 1312 participants (including 649 women and 663 men) developed lung cancer during an average follow-up of 14.8 (SD: 2.0) years for SWHS and 9.3 (SD: 1.6) years for SMHS. In multivariable analysis, no statistically significant associations were observed between glycemic index, glycemic load, and carbohydrate intake and lung cancer risk for either men or women. Similar results were observed among never smokers, and participants without history of lung disease, diabetes, or hypertension. Stratification by body mass index or menopause status also did not alter the findings. Our studies, conducted in populations who habitually have high-carbohydrate diets, provide no evidence that dietary glycemic index, glycemic load, or carbohydrate intake is associated with lung cancer risk.

Carbohydrates, glycemic index, glycemic load, and breast cancer risk: a systematic review and dose-response meta-analysis of prospective studies

Context

The investigation of dose-response associations between carbohydrate intake, glycemic index, glycemic load, and risk of breast cancer stratified by menopausal status, hormone receptor status, and body mass index (BMI) remains inconclusive.

Objective

A systematic review and dose-response meta-analyses was conducted to investigate these associations.

Data Sources

As part of the World Cancer Research Fund/American Institute for Cancer Research Continuous Update Project, PubMed was searched up to May 2015 for relevant studies on these associations.

Study Selection

Prospective studies reporting associations between carbohydrate intake, glycemic index, or glycemic load and breast cancer risk were included.

Data Extraction

Two investigators independently extracted data from included studies.

Results

Random-effects models were used to summarize relative risks (RRs) and 95%CIs. Heterogeneity between subgroups, including menopausal status, hormone receptor status, and BMI was explored using meta-regression. Nineteen publications were included. The summary RRs (95%CIs) for breast cancer were 1.04 (1.00-1.07) per 10 units/d for glycemic index, 1.01 (0.98-1.04) per 50 units/d for glycemic load, and 1.00 (0.96-1.05) per 50 g/d for carbohydrate intake. For glycemic index, the association appeared slightly stronger among postmenopausal women (summary RR per 10 units/d, 1.06; 95%CI, 1.02-1.10) than among premenopausal women, though the difference was not statistically significant (Pheterogeneity = 0.15). Glycemic load and carbohydrate intake were positively associated with breast cancer among postmenopausal women with estrogen-negative tumors (summary RR for glycemic load, 1.28; 95%CI, 1.08-1.52; and summary RR for carbohydrates, 1.13; 95%CI, 1.02-1.25). No differences in BMI were detected.

Conclusions

Menopausal and hormone receptor status, but not BMI, might be potential influencing factors for the associations between carbohydrate intake, glycemic index, glycemic load, and breast cancer.

Obesity, Dietary Factors, Nutrition, and Breast Cancer Risk

PURPOSE OF REVIEW

To synthesize the critical role of obesity-associated inflammation, dietary factors, and nutrition in determining breast cancer risk.

RECENT FINDINGS

Obesity-associated inflammation is strongly linked to breast cancer risk and progression, largely via two processes: inflammatory pathways and dysregulated metabolism. Cytokine production in excess adipose tissues creates a chronic inflammatory microenvironment, which favors tumor development. Lifestyle factors, including diet, have long been recognized as important determinants of breast cancer risk and mortality.

SUMMARY

Obesity increases the risk of developing breast cancer in both pre- and postmenopausal women and also negatively affects breast cancer recurrence and survival. Poor dietary habits characterized by the high intake of refined starches, sugar, and both saturated and trans-saturated fats, as well as the low intake of omega-3 fatty acids, natural antioxidants, and fiber, modulate inflammation and, thereby, appear to be linked to increased risk of breast cancer and mortality.

Association of whole grain intake with all-cause, cardiovascular, and cancer mortality: a systematic review and dose-response meta-analysis from prospective cohort studies

BACKGROUND/OBJECTIVES

Whole grains are rich source of nutrients and have shown beneficial effects on human health. This study was designed to systematically review the existing results and quantitatively assess the dose-response relationship of whole grain intake with all-cause and cause-specific mortality.

SUBJECTS/METHODS

We searched 'whole grain' or 'whole grains' in combination with 'mortality'' or 'cardiovascular disease' or 'cancer' through the Web of Science and PubMed databases till 20 January 2016. To be eligible for inclusion, publications should be prospective cohort studies and reported the influence of whole grain intake on human mortality. Relative risks (RRs) and 95% confidence intervals (CIs) from the included studies were pooled by a random effects model or fixed effect model.

RESULTS

We included 19 cohort studies from 17 articles, with 1 041 692 participants and 96 710 deaths in total, in the analyses. We observed an inverse relationship of whole grain intake with risk of total, cardiovascular disease and cancer mortality. The pooled RR was 0.84 (95% CI 0.81-0.88, n=9) for total mortality, 0.83 (95% CI 0.79-0.86, n=8) for CVD mortality and 0.94 (95% CI 0.87-1.01, n=14) for cancer mortality, comparing the highest intake of whole grain with the lowest category. For dose-response analysis, we found a nonlinear relationship of whole grain intake with risk of total, cardiovascular and cancer mortality. Each 28 g/d intake of whole grains was associated with a 9% (pooled RR: 0.91 (0.90-0.93)) lower risk for total mortality, 14% (pooled RR: 0.86 (0.83-0.89)) lower risk for CVD mortality and 3% (pooled RR: 0.97 (0.95-0.99)) lower risk for cancer mortality.

CONCLUSIONS

Our study shows that whole grain intake was inversely associated with risk of total, CVD and cancer mortality. Our results support current dietary guidelines to increase the intake of whole grains. Government officials, scientists and medical staff should take actions to promote whole grains intake.

Deciphering the molecular mechanism underlying anticancer activity of coumestrol in triple-negative breast cancer cells

Triple-negative breast cancer (TNBC) represents the highly aggressive subgroup of breast cancers with poor prognosis due to absence of estrogen receptor (ER). Therefore, alternative targeted therapies are required against ER-negative breast cancers. Coumestrol, a phytoestrogen inhibits cell growth of ER-negative breast cancer MDA-MB-231 cells; the exact mechanism has not yet been reported. Unlike normal cells, cancer cells contain elevated copper which play an integral role in angiogenesis. The current focus of the work was to identify any possible role of copper in coumestrol cytotoxic action against breast cancer MDA-MB-231 cells. Results demonstrated that coumestrol inhibited cell viability, induced ROS generation, DNA damage, G1/S cell cycle arrest, up-regulation of Bax and apoptosis induction via caspase-dependent mitochondrial mediated pathway in MDA-MB-231 cells. Further, addition of copper chelator, neocuproine and ROS scavenger, N-acetyl cysteine were ineffective in abrogating coumestrol-mediated apoptosis. This suggests non-involvement of copper and ROS in coumestrol-induced apoptosis. To account for coumestrol-mediated up-regulation of Bax and apoptosis induction, direct binding potential between coumestrol and Bax/Bcl-2 was studied using in silico molecular docking studies. We propose that coumestrol directly enters cells and combines with Bax/Bcl-2 to alter their structures, thereby causing Bax binding to the outer mitochondrial membrane and Bcl-2 release from the mitochondria to initiate apoptosis. Thus, non-copper targeted ROS independent DNA damage is the central mechanism of coumestrol in ER-negative MDA-MB-231 cells. These findings will be useful in better understanding of anticancer mechanisms of coumestrol and establishing it as a lead molecule for TNBC treatment.

Nature, Nurture, and Cancer Risks: Genetic and Nutritional Contributions to Cancer

It is speculated that genetic variants are associated with differential responses to nutrients (known as gene-diet interactions) and that these variations may be linked to different cancer risks. In this review, we critically evaluate the evidence across 314 meta-analyses of observational studies and randomized controlled trials of dietary risk factors and the five most common cancers (breast, lung, prostate, colorectal, and stomach). We also critically evaluate the evidence across 13 meta-analyses of observational studies of gene-diet interactions for the same cancers. Convincing evidence for association was found only for the intake of alcohol and whole grains in relation to colorectal cancer risk. Three nutrient associations had highly suggestive evidence and another 15 associations had suggestive evidence. Among the examined gene-diet interactions, only one had moderately strong evidence.

Carbohydrate nutrition and risk of adiposity-related cancers: results from the Framingham Offspring cohort (1991-2013)

Higher carbohydrate intake, glycaemic index (GI), and glycaemic load (GL) are hypothesised to increase cancer risk through metabolic dysregulation of the glucose-insulin axis and adiposity-related mechanisms, but epidemiological evidence is inconsistent. This prospective cohort study investigates carbohydrate quantity and quality in relation to risk of adiposity-related cancers, which represent the most commonly diagnosed preventable cancers in the USA. In exploratory analyses, associations with three site-specific cancers: breast, prostate and colorectal cancers were also examined. The study sample consisted of 3184 adults from the Framingham Offspring cohort. Dietary data were collected in 1991-1995 using a FFQ along with lifestyle and medical information. From 1991 to 2013, 565 incident adiposity-related cancers, including 124 breast, 157 prostate and sixty-eight colorectal cancers, were identified. Cox proportional hazards models were used to evaluate the role of carbohydrate nutrition in cancer risk. GI and GL were not associated with risk of adiposity-related cancers or any of the site-specific cancers. Total carbohydrate intake was not associated with risk of adiposity-related cancers combined or prostate and colorectal cancers. However, carbohydrate consumption in the highest v. lowest quintile was associated with 41 % lower breast cancer risk (hazard ratio (HR) 0·59; 95 % CI 0·36, 0·97). High-, medium- and low-GI foods were not associated with risk of adiposity-related cancers or prostate and colorectal cancers. In exploratory analyses, low-GI foods, were associated with 49 % lower breast cancer risk (HR 0·51; 95 % CI 0·32, 0·83). In this cohort of Caucasian American adults, associations between carbohydrate nutrition and cancer varied by cancer site. Healthier low-GI carbohydrate foods may prevent adiposity-related cancers among women, but these findings require confirmation in a larger sample.

Dietary glycemic index, glycemic load and cancer: An overview of the literature

AIMS

The aim of this paper is to provide an overview of the current evidence for associations between dietary glycemic index (GI) and dietary glycemic load (GL), and the risk of various types of cancer, and to summarize mechanisms proposed to explain the associations found.

DATA SYNTHESIS

Medline was searched for cohort studies, case-control studies, and meta-analyses, published up to February 2016, that examined associations between dietary GI/GL and cancer. Findings from the main meta-analyses showed a weak-to-moderate association of high dietary GI/GL with increased risk of some cancers. High dietary GI but not GL was significantly and consistently associated with increased colorectal cancer risk in both cohort and case-control studies. Dietary GL was directly associated with breast and endometrial cancer risk in cohort studies. Positive associations between dietary GI or GL and cancer risk were found more frequently in case-control studies than cohort studies. The main mechanism for these associations is thought to be chronic hyperinsulinemia. Insulin is itself a mitogen and also increases the bioactivity of insulin-like growth factors which can promote cancer by inhibiting apoptosis and stimulating cell proliferation.

CONCLUSIONS

The review has uncovered consistent evidence that high dietary GI is associated with increased risk of colorectal cancer, and that high dietary GL is associated with increased risk of breast and endometrial cancer. However the risk increases are small or moderate.

Cytotoxic activity of soy phytoestrogen coumestrol against human breast cancer MCF-7 cells: Insights into the molecular mechanism

Coumestrol is a phytoestrogen present in soybean products and recognized as potential cancer therapeutic agent against breast cancer. However, the clear molecular mechanism of anticancer-activity of coumestrol in breast carcinoma has not been reported. It is well established that copper levels are elevated in different malignancies. Therefore, the objective of this study was to investigate the copper-dependent cytotoxic action of coumestrol in human breast cancer MCF-7 cells. Results showed that coumestrol inhibited proliferation and induced apoptosis in MCF-7 cells, which was prevented by copper chelator neocuproine and ROS scavengers. Coumestrol treatment induced ROS generation coupled to DNA fragmentation, up-regulation of p53/p21, cell cycle arrest at G1/S phase, mitochondrial membrane depolarization and caspases 9/3 activation. All these effects were suppressed by ROS scavengers and neocuproine. These results suggest that coumestrol targets elevated copper for redox cycling to generate ROS leading to DNA fragmentation. DNA damage leads to p53 up-regulation which directs the cell cycle arrest at G1/S phase and promotes caspase-dependent apoptosis of MCF-7 cells. In conclusion, copper targeted ROS-mediated p53-dependent mechanism better explains the cytotoxic action of coumestrol in MCF-7 cells. Thus, targeting elevated copper levels might be a potential therapeutic strategy for selective cytotoxic action against malignant cells.

Phthalate exposure, flavonoid consumption and breast cancer risk among Mexican women

OBJECTIVE

To evaluate if selected phthalate exposure and flavonoid intake interact on breast cancer (BC) risk.

MATERIAL AND METHODS

Interviews and urine samples were obtained from 233 women with histologically confirmed BC and 221 healthy controls matched by age and place of residence, from various states of northern Mexico. Urinary metabolites concentrations of diethyl phthalate (DEP), butyl benzyl phthalate (BBzP) and dioctyl phthalate (DOP) were determined by solid-phase extraction coupled with high-performance liquid chromatography/isotope dilution/tandem mass spectrometry. Using a semiquantitative food frequency questionnaire, consumption of five types of flavonoids (anthocyanidins, flavan-3-ols, flavanones, flavones and flavonols) was estimated according to three food groups: vegetables, fruits and legumes-oil seeds.

RESULTS

A higher intake of anthocyanidins and flavan-3-ols (from vegetables), synergistically increased the negative association between BBzP and BC. No other significant flavonoid-phthalate multiplicative interactions on the risk for BC were found.

CONCLUSION

The consumption of some flavonoids may interact with exposure to phthalates on the risk of BC. Epidemiological and underlying mechanisms information is still insufficient and requires further investigations.

A Sucrose-Enriched Diet Promotes Tumorigenesis in Mammary Gland in Part through the 12-Lipoxygenase Pathway

Epidemiologic studies have shown that dietary sugar intake has a significant impact on the development of breast cancer. One proposed mechanism for how sugar impacts cancer development involves inflammation. In the current study, we investigated the impact of dietary sugar on mammary gland tumor development in multiple mouse models, along with mechanisms that may be involved. We found that sucrose intake in mice comparable with levels of Western diets led to increased tumor growth and metastasis, when compared with a nonsugar starch diet. This effect was ascribed in part to increased expression of 12-lipoxygenase (12-LOX) and its arachidonate metabolite 12-hydroxy-5Z,8Z,10E,14Z-eicosatetraenoic acid (12-HETE). We determined that fructose derived from the sucrose was responsible for facilitating lung metastasis and 12-HETE production in breast tumors. Overall, our data suggested that dietary sugar induces 12-LOX signaling to increase risks of breast cancer development and metastasis.

Cu(II)-coumestrol interaction leads to ROS-mediated DNA damage and cell death: a putative mechanism for anticancer activity

Phytoestrogens have attracted considerable interest as natural alternatives to hormone replacement therapy and their potential as cancer therapeutic agents. Among phytoestrogens, coumestrol has shown multipharmacological properties such as antiinflammatory, neuroprotective, osteoblastic differentiation and anticancer. Though several studies have described anticancer effects of coumestrol, a clear underlying molecular mechanism has not been elucidated. Unlike normal cells, cancer cells contain elevated copper levels that play an integral role in angiogenesis. Copper is an important metal ion associated with the chromatin DNA, particularly with guanine. Thus, targeting copper in cancer cells can serve as effective anticancer strategy. Using human peripheral lymphocytes, we assessed lipid peroxidation, protein carbonylation, reactive oxygen species (ROS) generation, DNA damage and apoptosis by coumestrol in the presence of exogenously added Cu(II) in cells to simulate malignancy-like condition. Results showed that Cu(II)-coumestrol interaction leads to lipid peroxidation and protein carbonylation (markers of oxidative stress), DNA fragmentation and apoptosis in treated lymphocytes. Further, incubation of lymphocytes with ROS scavengers and membrane-permeant copper chelator, neocuproine, resulted in inhibition of DNA damage and apoptosis. This suggests that coumestrol engages in redox cycling of Cu(II) to generate ROS that leads to DNA fragmentation and apoptosis. In conclusion, this is the first report showing that coumestrol targets cellular copper to induce prooxidant death in malignant cells. We believe that such a prooxidant cytotoxic mechanism better explains the anticancer activity of coumestrol. These findings will provide significant insights into the development of new chemical molecules with better copper-chelating and prooxidant properties against cancer cells.

The Role of Glucose Modulation and Dietary Supplementation in Patients With Central Nervous System Tumors

OPINION STATEMENT

Central nervous system gliomas are the most common primary brain tumor, and these are most often high-grade gliomas. Standard therapy includes a combination of surgery, radiation, and chemotherapy which provides a modest increase in survival, but virtually, no patients are cured, the overall prognosis remains poor, and new therapies are desperately needed. Tumor metabolism is a well-recognized but understudied therapeutic approach to treating cancers. Dietary and nondietary modulation of glucose homeostasis and the incorporation of dietary supplements and other natural substances are potentially important interventions to affect cancer cell growth, palliate symptoms, reduce treatment-associated side effects, and improve the quality and quantity of life in patients with cancer. These approaches are highly desired by patients. However, they can be financially burdensome, associated with toxicities, and have, on occasion, reduced the efficacy of proven therapies and negatively impacted patient outcomes. The lack of rigorous scientific data evaluating almost all diet and supplement-based therapies currently limits their incorporation into standard oncologic practice. Rigorous studies are needed to document and improve these potentially useful approaches in patients with brain and other malignancies.

Effect of low or high glycemic load diets on experimentally induced mammary carcinogenesis in rats

SCOPE

High glycemic load diets have been associated with increased breast cancer risk in population-based studies, but the evidence is mixed. This investigation determined whether diets differing in glycemic load affected the carcinogenic process using a preclinical model.

METHODS AND RESULTS

Human diets, formulated to differ 2-fold in glycemic load, were evaluated in the 1-methyl-nitrosourea-induced (37.5 mg/kg) mammary carcinogenesis model. Cancer incidence (23.3 versus 50.0%, p = 0.032), multiplicity, (0.40 versus 1.03, p = 0.030) and burden, (0.62 versus 1.19 g/rat, p = 0.037) were reduced in the low versus high glycemic load diets, respectively. However, the low glycemic protective effect was attenuated when two purified diets that differed in resistant starch and simulated the glycemic effects of the human diets were fed. Protection was associated with alterations in markers of cell growth regulation.

CONCLUSION

Our findings show that human low or high glycemic load dietary patterns differentially affect the carcinogenic response in a nondiabetic rodent model for breast cancer. However, factors that are associated with these patterns, in addition to dietary carbohydrate availability, appear to account for the differences observed.

Dietary fiber, whole grains, carbohydrate, glycemic index, and glycemic load in relation to risk of prostate cancer

BACKGROUND

The relationships between dietary fiber, whole grains, carbohydrate, glycemic index (GI), glycemic load (GL), and prostate cancer risk are unclear. We conducted a systematic review and meta-analysis to investigate these associations.

METHODS

Relevant studies were identified by a search of PubMed database and EMBASE database up to April 2015. A random effects model was used to calculate the summary relative risks (RRs) and their corresponding 95% confidence intervals (CIs).

RESULTS

Twenty-seven epidemiological studies (18 case-control studies and nine cohort studies) were included in the final analysis. The pooled RRs of prostate cancer were 0.94 (95% CI 0.85-1.05, P=0.285), 1.13 (95% CI 0.98-1.30, P=0.095), 0.96 (95% CI 0.81-1.14, P=0.672), 1.06 (95% CI 0.96-1.18, P=0.254), and 1.04 (95% CI 0.91-1.18, P=0.590) for dietary fiber, whole grains, carbohydrate, GI, and GL, respectively. There was no evidence of significant publication bias based on the Begg's test and Egger's test.

CONCLUSION

The findings of this meta-analysis indicate that, based on available information, dietary fiber, whole grains, carbohydrate, GI, and GL are not associated with the risk of prostate cancer.

Weight loss interventions for breast cancer survivors: impact of dietary pattern

Body weight management is not emphasized in clinical practice guidelines for breast cancer survivors, reflecting the lack of evidence that weight loss improves prognosis. Even if this situation changes, the optimal design for weight loss interventions is unclear. We conducted a 6-month non-randomized, controlled weight loss intervention in 249 post-menopausal breast cancer survivors. This paper reports effects on two secondary endpoints, change in body weight and composition. Participants were predominantly non-Hispanic whites (89%) with a mean age of 54.9 ± 9.2 years, a mean BMI of 29.0 ± 2.6 kg/m: ² and an average of 43 ± 5% body fat. Two dietary interventions, low fat or low carbohydrate, were investigated and consisted of a 42 day cycle of menus and recipes. Weight loss counseling and anthropometric assessment were provided at monthly clinic visits. One hundred ninety-two women completed the trial (77% retention). In comparison to the nonintervention control, both intervention arms achieved significant decreases in body weight (12.5%), body fat (27.5%), waist circumference (9.5%), and hip circumference (7.8%) (all p < 0.001) with minimal effects on lean mass (1.3% decrease). Median time to 5 and 10% weight loss was 2 (95% confidence interval = 1 to 3) and 4 (95% confidence interval = 3 to 5) months, respectively, and 23% of participants experienced ≥ 15% weight loss. Loss of body weight and fat mass was rapid and substantial irrespective of dietary approach when a structured program was provided with monthly anthropometric assessment and weight loss counseling.

Dietary Protocols to Maximize Disease Reversal and Long-Term Safety

This article covers some important concepts and controversies in modern nutritional science. It describes a diet style designed to maximize health, longevity, and disease reversal—foundationally structured on the quality and comprehensive adequacy of nutrients rather than the balance of macronutrients, as is more popular today. I call such a diet, which attempts to optimize micronutrients, a nutritarian diet. I will review a small case series demonstrating typical results in diabetics and some of my clinical observations over the last 25 years treating people with a nutritarian diet, which could be either vegan or flexitarian. I will also discuss health concerns observed from an unsupplemented vegan diet, specifically the risk of depression and later life dementia in individuals with enhanced need for long-chain omega-3 fatty acids.

Association between vegetable, fruit and carbohydrate intake and breast cancer risk in relation to physical activity

BACKGROUND

Although the nutritional may exert effect on the breast cancer risk, it is not clear whether the role diet is the same in sedentary and physically active women. The aim of this study was to evaluate the association between fruit, vegetable and carbohydrate intake and the risk of breast cancer among Polish women considering their physical activity level.

MATERIALS AND METHODS

A case-control study was conducted that included 858 women with histological confirmed breast cancer and 1,085 controls, free of any cancer diagnosis, aged 28-78 years. The study was based on a self-administered questionnaire to ascertain physical activity, dietary intake, sociodemographic characteristics, reproductive factors, family history of breast cancer, current weight and high, and other lifestyle factors. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated in unconditional logistic regression analyses including a broad range of potential confounders.

RESULTS

With comparison of the highest vs lowest quartile of intake, strong significant associations were observed for total vegetables (OR=0.37, 95%CI=0.20-0.69 P for trend <0.01 and OR=0.53, 95%CI=0.29-0.96, P for trend <0.02), and total fruits (OR=0.47, 95%CI=0.25-0.87, P for trend <0.05 and OR=0.47, 95%CI=0.24-0.90, P for trend <0.02) among women characterized by the lowest and the highest quartile of physical activity. No associations were observed for total carbohydrate intake. Additional analysis showed a positive association for sweets and desert intake among women in the lowest quartile of physical activity (OR=3.49, 95%CI=1.67-7.30, P for trend <0.009) for extreme quartiles of intake comparing to the referent group.

CONCLUSIONS

The results suggest that a higher consumption of vegetable and fruit may be associated with a decreased risk of breast cancer, especially among women who were low or most physically active throughout their lifetimes. These findings do not support an association between diet high in carbohydrate and breast cancer. However, a higher intake of sweets and deserts may by associated with an increased risk of breast cancer among women who were less physically active.

Adolescent and Early Adulthood Dietary Carbohydrate Quantity and Quality in Relation to Breast Cancer Risk

BACKGROUND

We investigated quantity and quality of dietary carbohydrate as well as insulin load and insulin index during adolescence and also early adulthood in relation to risk of breast cancer in the Nurses' Health Study II.

METHODS

During 20 years of follow-up of 90,534 premenopausal women who completed a diet questionnaire in 1991, 2,833 invasive breast cancer cases were documented. In 1998, 44,263 of these women also completed a questionnaire about their diet during high school; among these women, we documented 1,118 cases of breast cancer. Multivariable-adjusted Cox proportional hazards regression was used to model relative risks (RR) and 95% confidence intervals (95% CI) for breast cancer across categories of dietary carbohydrate, glycemic index (GI), glycemic load (GL), as well as insulin load and insulin index scores.

RESULTS

Adolescent or early adult intakes of GI or GL were not associated with risk of breast cancer. Comparing women in the highest versus lowest quintile, the multivariable-adjusted RRs were 1.14 (0.95-1.38) for adolescent GI scores and 1.03 (0.91-1.16) for early adulthood GI scores. We also did not observe associations with insulin index and insulin load scores in adolescence or early adulthood and breast cancer risk.

CONCLUSIONS

We found that diets high in GI, GL, insulin index, and insulin load during adolescence or early adulthood were not associated with an increased risk of breast cancer in this cohort study.

IMPACT

Diets with a high glucose or insulin response in adolescence or early adulthood were not significant predictors of breast cancer incidence.

Mediterranean diet pyramid: a proposal for Italian people

Bread was a staple in the traditional Mediterranean diet of the early 1960s, as well as nowadays; however, it was a stone ground sourdough bread in Nicotera and probably in the Greek cohorts of the Seven Countries Study. In the present review, the nutritional characteristics of this food are analyzed in relation to its protective effects on coronary heart disease, metabolic diseases and cancer. According to our traditions, cultural heritage and scientific evidence, we propose that only cereal foods with low glycemic index (GI) and rich in fiber have to be placed at the base of the Mediterranean diet pyramid, whereas refined grains and high GI starchy foods have to be sited at the top.

A high dietary glycemic index increases total mortality in a Mediterranean population at high cardiovascular risk

OBJECTIVE

Different types of carbohydrates have diverse glycemic response, thus glycemic index (GI) and glycemic load (GL) are used to assess this variation. The impact of dietary GI and GL in all-cause mortality is unknown. The objective of this study was to estimate the association between dietary GI and GL and risk of all-cause mortality in the PREDIMED study.

MATERIAL AND METHODS

The PREDIMED study is a randomized nutritional intervention trial for primary cardiovascular prevention based on community-dwelling men and women at high risk of cardiovascular disease. Dietary information was collected at baseline and yearly using a validated 137-item food frequency questionnaire (FFQ). We assigned GI values of each item by a 5-step methodology, using the International Tables of GI and GL Values. Deaths were ascertained through contact with families and general practitioners, review of medical records and consultation of the National Death Index. Cox regression models were used to estimate multivariable-adjusted hazard ratios (HR) and their 95% CI for mortality, according to quartiles of energy-adjusted dietary GI/GL. To assess repeated measures of exposure, we updated GI and GL intakes from the yearly FFQs and used Cox models with time-dependent exposures.

RESULTS

We followed 3,583 non-diabetic subjects (4.7 years of follow-up, 123 deaths). As compared to participants in the lowest quartile of baseline dietary GI, those in the highest quartile showed an increased risk of all-cause mortality [HR = 2.15 (95% CI: 1.15-4.04); P for trend  = 0.012]. In the repeated-measures analyses using as exposure the yearly updated information on GI, we observed a similar association. Dietary GL was associated with all-cause mortality only when subjects were younger than 75 years.

CONCLUSIONS

High dietary GI was positively associated with all-cause mortality in elderly population at high cardiovascular risk.

Do statins increase and Mediterranean diet decrease the risk of breast cancer?

BACKGROUND

Physical exercise and healthy dietary habits are recommended to prevent breast cancer.

DISCUSSION

Increased intake of omega-3 fatty acids associated with decreased omega-6 - resulting in higher omega-3 to omega-6 ratio compared with Western-type diet - is inversely associated with breast cancer risk. The modernized Mediterranean diet with high omega-3 to omega-6 ratio, high fiber and polyphenol intake, and consumption of low-glycemic index foods reduces overall cancer risk and specifically breast cancer risk. It has been suggested that consuming no more than one alcoholic drink per day, preferably wine, is preferable. Eliminating environmental contaminants, including endocrine disruptors, and favoring organic foods to increase polyphenol intake and the omega-3 to omega-6 ratios were also shown to be beneficial. Cholesterol-lowering statins may decrease antitumor defenses; are toxic for the mitochondria; decrease the omega-3 to omega-6 ratio; increase body mass index, insulin resistance and diabetic risk; and have been associated with an increased breast cancer risk.

SUMMARY

Therefore, as well as making lifestyle changes to decrease breast cancer risk, we argue that physicians should carefully consider (and often avoid) therapies that may increase breast cancer or diabetes risk in high-risk women and women who wish to decrease their breast cancer risk.