Dietary fiber is associated with circulating concentrations of C-reactive protein in breast cancer survivors: the HEAL study

Effects of Functional and Nutraceutical Foods in the Context of the Mediterranean Diet in Patients Diagnosed with Breast Cancer

Several studies report that breast cancer survivors (BCS) tend to have a poor diet, as fruit, vegetable, and legume consumption is often reduced, resulting in a decreased intake of nutraceuticals. Moreover, weight gain has been commonly described among BCS during treatment, increasing recurrence rate and mortality. Improving lifestyle and nutrition after the diagnosis of BC may have important benefits on patients' general health and on specific clinical outcomes. The Mediterranean diet (MD), known for its multiple beneficial effects on health, can be considered a nutritional pool comprising several nutraceuticals: bioactive compounds and foods with anti-inflammatory and antioxidant effects. Recent scientific advances have led to the identification of nutraceuticals that could amplify the benefits of the MD and favorably influence gene expression in these patients. Nutraceuticals could have beneficial effects in the postdiagnostic phase of BC, including helping to mitigate the adverse effects of chemotherapy and radiotherapy. Moreover, the MD could be a valid and easy-to-follow option for managing excess weight. The aim of this narrative review is to evaluate the recent scientific literature on the possible beneficial effects of consuming functional and nutraceutical foods in the framework of MD in BCS.

Cardiorespiratory fitness, visceral fat, and body fat, but not dietary inflammatory index, are related to C-reactive protein in cancer survivors

BACKGROUND

The control of chronic inflammation has emerged as a target for improving the health of cancer survivors (CS).

AIM

To examine differences in fitness and dietary characteristics of CS when grouped by low vs. moderate to high serum C-reactive protein (CRP).

METHODS

CS (N = 26, mean age = 68 ± 12 years) were evaluated for body mass index (BMI), body composition, cardiorespiratory fitness, dietary intake, dietary inflammatory index (DII), and serum CRP. Participants were assigned to one of two groups based on serum CRP concentrations: low CRP (≤1 mg/L) (LWC; n = 13) or moderate to high (CRP > 1 mg/L) (MHC; n = 13) and t-tests compared them. Data are presented as mean ± SD.

RESULTS

LWC had higher VO₂peak values (mL/kg/min) (p = 0.0003), and lower visceral fat area (cm²) (p = 0.02) and body fat mass (kg) (p = 0.04). Secondary analysis using Pearson's correlation coefficients, including all current study participant data, found significant negative relationships between CRP and total dietary fat intake (p = 0.02), saturated fat (p = 0.03), and polyunsaturated fat (p = 0.03).

CONCLUSION

CS with moderate to high serum CRP concentrations had higher fat mass, visceral fat mass, and lower cardiorespiratory fitness. There was a significant negative relationship between dietary, fat, polyunsaturated and saturated fat, and CRP. However, these dietary fat related findings warrant further investigation. To summarize, improving cardiorespiratory fitness, maintaining lower body fat, may be helpful in altering chronic inflammation in CS.

Short-chain fatty acids, prebiotics, synbiotics, and systemic inflammation: a systematic review and meta-analysis

BACKGROUND

Prebiotic soluble fibers are fermented by beneficial bacteria in the colon to produce short-chain fatty acids (SCFAs), which are proposed to have systemic anti-inflammatory effects.

OBJECTIVE

This review examines the effect of SCFAs, prebiotics, and pre- and probiotic combinations (synbiotics) on systemic inflammation.

DESIGN

Relevant English language studies from 1947 to May 2017 were identified with the use of online databases. Studies were considered eligible if they examined the effects of SCFAs, prebiotics, or synbiotics; were delivered orally, intravenously, or per rectum; were on biomarkers of systemic inflammation in humans; and performed meta-analysis where possible.

RESULTS

Sixty-eight studies were included. Fourteen of 29 prebiotic studies and 13 of 26 synbiotic studies reported a significant decrease in ≥1 marker of systemic inflammation. Eight studies compared prebiotic and synbiotic supplementation, 2 of which reported a decrease in inflammation with synbiotics only, with 1 reporting a greater anti-inflammatory effect with synbiotics than with prebiotics alone. Meta-analyses indicated that prebiotics reduce C-reactive protein (CRP) [standardized mean difference (SMD): -0.60; 95% CI: -0.98, -0.23], and synbiotics reduce CRP (SMD: -0.40; 95% CI: -0.73, -0.06) and tumor necrosis factor-α (SMD -0.90; 95% CI: -1.50, -0.30).

CONCLUSIONS

There is significant heterogeneity of outcomes in studies examining the effect of prebiotics and synbiotics on systemic inflammation. Approximately 50% of included studies reported a decrease in ≥1 inflammatory biomarker. The inconsistency in reported outcomes may be due to heterogeneity in study design, supplement formulation, dosage, duration, and subject population. Nonetheless, meta-analyses provide evidence to support the systemic anti-inflammatory effects of prebiotic and synbiotic supplementation.

Pre-diagnosis diet and survival after a diagnosis of ovarian cancer

Background:

The relationship between diet and survival after ovarian cancer diagnosis is unclear as a result of a limited number of studies and inconsistent findings.

Methods:

We examined the association between pre-diagnostic diet and overall survival in a population-based cohort (n=811) of Australian women diagnosed with invasive epithelial ovarian cancer between 2002 and 2005. Diet was measured by validated food frequency questionnaire. Deaths were ascertained up to 31 August 2014 via medical record review and Australian National Death Index linkage. We conducted Cox proportional hazards regression analysis, controlling for diagnosis age, tumour stage, grade and subtype, residual disease, smoking status, body mass index, physical activity, marital status, and energy intake.

Results:

We observed improved survival with highest compared with lowest quartile of fibre intake (hazard ratio (HR)=0.69, 95% CI: 0.53–0.90, P-trend=0.002). There was a suggestion of better survival for women with highest compared with lowest intake category of green leafy vegetables (HR=0.79, 95% CI: 0.62–0.99), fish (HR=0.74, 95% CI: 0.57–0.95), poly- to mono-unsaturated fat ratio (HR=0.76, 95% CI: 0.59–0.98), and worse survival with higher glycaemic index (HR=1.28, 95% CI: 1.01–1.65, P-trend=0.03).

Conclusions:

The associations we observed between healthy components of diet pre-diagnosis and ovarian cancer survival raise the possibility that dietary choices after diagnosis may improve survival.

The association between dietary inflammatory index and risk of colorectal cancer among postmenopausal women: results from the Women's Health Initiative

PURPOSE

Inflammation is a process central to carcinogenesis and in particular to colorectal cancer (CRC). Previously, we developed a dietary inflammatory index (DII) from extensive literature review to assess the inflammatory potential of diet. In the current study, we utilized this novel index in the Women's Health Initiative to prospectively evaluate its association with risk of CRC in postmenopausal women.

METHODS

The DII was calculated from baseline food frequency questionnaires administered to 152,536 women aged 50-79 years without CRC at baseline between 1993 and 1998 and followed through 30 September 2010. Incident CRC cases were ascertained through a central physician adjudication process. Multiple covariate-adjusted Cox proportional hazards regression models were used to estimate hazard ratios (HR) and 95 % confidence intervals (95 % CI) for colorectal, colon (proximal/distal locations), and rectal cancer risk, by DII quintiles (Q).

RESULTS

During an average 11.3 years of follow-up, a total of 1,920 cases of CRC (1,559 colon and 361 rectal) were identified. Higher DII scores (representing a more pro-inflammatory diet) were associated with an increased incidence of CRC (HRQ5-Q1 1.22; 95 % CI 1.05, 1.43; p trend = 0.02) and colon cancer, specifically proximal colon cancer (HRQ5-Q1 1.35; 95 % CI 1.05, 1.67; p trend = 0.01) but not distal colon cancer (HRQ5-Q1 0.84; 95 % CI 0.61, 1.18; p trend = 0.63) or rectal cancer (HRQ5-Q1 1.20; 95 % CI 0.84, 1.72; p trend = 0.65).

CONCLUSION

Consumption of pro-inflammatory diets is associated with an increased risk of CRC, especially cancers located in the proximal colon. The absence of a significant association for distal colon cancer and rectal cancer may be due to the small number of incident cases for these sites. Interventions that may reduce the inflammatory potential of the diet are warranted to test our findings, thus providing more information for colon cancer prevention.

Effects of fermentable dietary fiber supplementation on oxidative and inflammatory status in hemodialysis patients

BACKGROUND

Increased oxidative stress, inflammation, and malnutrition are important risk factors for cardiovascular disease in hemodialysis patients. High dietary intake in soluble fiber can decrease the elevated level of serum c-reactive protein in patients with chronic kidney disease. The aim of this study was to evaluate the effect of supplementation of dietary water-soluble fiber on oxidative and inflammatory status in hemodialysis patients.

METHODS

In a randomized placebo-controlled trial, we examined the effects of supplementation of dietary fiber on oxidative and inflammatory status in hemodialysis patients. 124 hemodialysis patients were randomly selected and given either 10 g/d, 20 g/d of fiber or placebo for 6 weeks. Anthropometric indices and 24 h diet recall intake was assessed. The CRP, albumin, triglyceride, total cholesterol, LDL, HDL were measured before and after of the intervention. The malondialdehyde (MDA), total antioxidant capacity (T-AOC), Cu-Zn superoxidase dismutase (SOD), glutathione peroxidase (GSH-Px) high-sensitivity C-Reactive protein (hs-CRP), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and interleukin-8 (IL-8) were measured.

RESULTS

After 6 weeks of intervention, in 10 g and 20 g/d of fiber supplement groups, TC and LDL level and TC:LDL ratio were significantly decreased, T-AOC was significantly increased, MDA level was significantly deceased, TNF-α, IL-6, IL-8 and CRP level were significantly deceased. TG, HDL, SOD and GSH-Px had no change before and after the intervention.

CONCLUSIONS

Dietary fermentable fiber supplementation improved lipid profile and oxidative status, decreased systemic inflammatory state of hemodialysis patients. Thus, it may decrease the risk of cardiovascular events in these patients.

Associations of dietary fiber intake with long-term predicted cardiovascular disease risk and C-reactive protein levels (from the National Health and Nutrition Examination Survey Data [2005-2010])

Dietary fiber intake might reduce cardiovascular risk factor levels and, in turn, might lower the long-term risk of cardiovascular disease (CVD). A total of 11,113 subjects, aged 20 to 79 years with no history of CVD, from the 2005 to 2010 National Health and Nutrition Examination Survey were included in the present study to examine associations of dietary fiber intake with predicted lifetime CVD risk and C-reactive protein levels. Dietary fiber intake showed a significant gradient association with the likelihood of having a low or an intermediate predicted lifetime CVD risk among young and middle-age adults. In fully adjusted multinomial logistic models, dietary fiber intake was related to a low lifetime CVD risk with an odds ratio of 2.71 (95% confidence interval 2.05 to 3.59) in the young adults and 2.13 (95% confidence interval 1.42 to 3.20) in the middle-age adults and was related to an intermediate lifetime risk of 2.65 (95% confidence interval 1.79 to 3.92) in the young and 1.98 (95% confidence interval 1.32 to 2.98) in the middle-age adults compared with a high lifetime risk. A significant inverse linear association was seen between dietary fiber intake and log-transformed C-reactive protein levels with a regression coefficient ± standard error of -0.18 ± 0.04 in the highest quartile of fiber intake compared with the lowest fiber intake. In conclusion, these data suggest that dietary fiber intake is independently associated with the predicted lifetime CVD risk, especially in young and middle-age adults. A greater amount of dietary fiber intake might be associated with lower C-reactive protein levels.

Fiber intake and inflammation in type 1 diabetes

BACKGROUND

Higher intake of dietary fiber is associated with lower risk of coronary heart disease, the leading cause of mortality among people with type 1 diabetes. The protective effect includes the anti-inflammatory properties of some foods. Population-based studies have shown an inverse association between some nutritional habits and high sensitive -C-reactive protein (hs-CRP). This study aimed to ascertain the association between fiber intake and hs-CPR levels in patients with type 1 diabetes.

METHODS

This cross-sectional study was conducted with 106 outpatients with type 1 diabetes; age 40 ± 11 years; diabetes duration of 18 ± 8.8 years. Dietary intake was evaluated by 3-day weighed-diet records. Patients were categorized in 2 groups, according to fiber intake (>20 g/day and <20 g/day).

RESULTS

The group with fiber intake > 20 g/day had lower hs-CRP levels [median (25(th-)75(th)) 0.7 mg/dl (0.4-2.4) vs. 1.9 mg/dl (1.0-4.4); P = 0.002], than the other group. Controlled for HbA1c and energy intake, an inverse relation was observed between hs-CRP levels and total fiber [ß = - 0.030 (SE: 0.0120), P = 0.02], soluble fiber [ß = - 0.078 (SE: 0.0421), P = 0.06] and insoluble fiber [ß = - 0.039 (SE: 0.01761), P = 0.026]. Even, after additional adjustment fibers remained associated with lower hs-CRP levels. Total fibers were stratified in 4 groups: < 10 g/day, from 10 to < 20 g/day, from 20 to 30 g/day and > 30 g/day. Compared to the group who ingested < 10 g/day of total fiber (referent group), the group who consumed > 30 g/d had significantly lower hs-CRP levels [-2.45 mg/L, P = 0.012] independent of the HbA1c values.

CONCLUSIONS

The present study suggests that an increased consumption of dietary fiber > 30 g/day may play a role in reducing inflammation in individuals with type 1 diabetes.

Inflammatory and microenvironmental factors involved in breast cancer progression

The primary reason for the high mortality rate of breast cancer is metastasis, which can result in a poor survival rate. The tumor environment is important for promotion and invasion of cancer cells. Recent studies have shown that inflammation is associated with breast cancer. Therefore, it is important to investigate the role of the inflammatory and microenvironment in breast cancer progression and metastasis. The present review summarizes some of the markers for inflammation and breast cancer invasion, which may aid in the design of an appropriate therapy for metastatic breast cancer. The following four inflammatory markers are discussed in this review: (1) Tumor associated macrophages (TAMs); (2) Matrix metalloproteinases (MMPs); (3) Sphingosine 1-phosphate (S1P); (4) C-reactive protein (CRP). TAMs are commonly found in breast cancer patients, and high infiltration is positively correlated with poor prognosis and low survival rate. MMPs are well-known for their roles in the degradation of ECM components when cancer cells invade and migrate. MMPs are also associated with inflammation through recruitment of a variety of stromal cells such as fibroblasts and leukocytes. S1P is an inflammatory lipid and is involved in various cellular processes such as proliferation, survival, and migration. Recent studies indicate that S1P participates in breast cancer invasion in various ways. CRP is used clinically to indicate the outcome of cancer patients as well as acute inflammatory status. This review summarizes the current understanding on the role of S1P in CRP expression which promotes the breast epithelial cell invasion, suggesting a specific mechanism linking inflammation and breast cancer. The present review might be useful for understanding the relationship between inflammation and breast cancer for the development of pharmacological interventions that may control the primary molecules involved in the breast cancer microenvironment.

The interplay between fiber and the intestinal microbiome in the inflammatory response

Fiber intake is critical for optimal health. This review covers the anti-inflammatory roles of fibers using results from human epidemiological observations, clinical trials, and animal studies. Fiber has body weight-related anti-inflammatory activity. With its lower energy density, a diet high in fiber has been linked to lower body weight, alleviating obesity-induced chronic inflammation evidenced by reduced amounts of inflammatory markers in human and animal studies. Body weight-unrelated anti-inflammatory activity of fiber has also been extensively studied in animal models in which the type and amount of fiber intake can be closely monitored. Fermentable fructose-, glucose-, and galactose-based fibers as well as mixed fibers have shown systemic and local intestinal anti-inflammatory activities when plasma inflammatory markers and tissue inflammation were examined. Similar anti-inflammatory activities have also been demonstrated in some human studies that controlled total fiber intake. The anti-inflammatory activities of synbiotics (probiotics plus fiber) were reviewed as well, but there was no convincing evidence indicating higher efficacy of synbiotics compared with that of fiber alone. Adverse effects have not been observed with the amount of fiber intake or supplementation used in studies, although patients with Crohn's disease may be more sensitive to inulin intake. Several possible mechanisms that may mediate the body weight-unrelated anti-inflammatory activity of fibers are discussed based on the in vitro and in vivo evidence. Fermentable fibers are known to affect the intestinal microbiome. The immunomodulatory role of the intestinal microbiome and/or microbial metabolites could contribute to the systemic and local anti-inflammatory activities of fibers.

A low-fat dietary pattern and risk of metabolic syndrome in postmenopausal women: the Women's Health Initiative

OBJECTIVE

Nutrition plays an important role in metabolic syndrome etiology. We examined whether the Women's Health Initiative (WHI) Dietary Modification Trial influenced metabolic syndrome risk.

MATERIALS/METHODS

48,835 postmenopausal women aged 50-79 years were randomized to a low-fat (20% energy from fat) diet (intervention) or usual diet (comparison) for a mean of 8.1 years. Blood pressure, waist circumference and fasting blood measures of glucose, HDL-cholesterol and triglycerides were measured on a subsample (n=2816) at baseline and years 1, 3 and 6 post-randomization. Logistic regression estimated associations of the intervention with metabolic syndrome risk and use of cholesterol-lowering and hypertension medications. Multivariate linear regression tested associations between the intervention and metabolic syndrome components.

RESULTS

At year 3, but not years 1 or 6, women in the intervention group (vs. comparison) had a non-statistically significant lower risk of metabolic syndrome (OR=0.83, 95%CI 0.59-1.18). Linear regression models simultaneously modeling the five metabolic syndrome components revealed significant associations of the intervention with metabolic syndrome at year 1 (p<0.0001), but not years 3 (p=0.19) and 6 (p=0.17). Analyses restricted to intervention-adherent participants strengthened associations at years 3 (p=0.05) and 6 (p=0.06). Cholesterol-lowering and hypertension medication use was 19% lower at year 1 for intervention vs. comparison group women (OR=0.81, 95% CI 0.60-1.09).Over the entire trial, fewer intervention vs. comparison participants used these medications (26.0% vs. 29.9%), although results were not statistically significant (p=0.89).

CONCLUSIONS

The WHI low-fat diet may influence metabolic syndrome risk and decrease use of hypertension and cholesterol-lowering medications. Findings have potential for meaningful clinical translation.

Diet components associated with perceived fatigue in breast cancer survivors

Little is known about the contribution of diet components independent of body composition to persistent fatigue in breast cancer survivors. Therefore, our study aim was to determine the associations among dietary intake and fatigue in relation to and independent of adiposity and physical activity (PA) in breast cancer survivors. Baseline data from 42 breast cancer survivors enrolled in a randomised exercise trial were analysed: fatigue (Functional Assessment of Cancer Therapy for fatigue), diet components (3-day diet record), body mass index, per cent body fat (dual-energy X-ray absorptiometry) and PA (accelerometer). The mean age was 54 ± 9 years with an average body mass index of 30.5 ± 8.1 kg/m(2). Fatigue was positively associated with % of kcal/day fat intake (r = 0.31, P < 0.05) and inversely related to fibre g/day (r = 0.38, P < 0.05) and carbohydrate g/day intake (r = 0.31, P < 0.05). Mean fatigue was greater for participants eating <25 g/day of fibre compared with >25 g/day of fibre (15.7 ± 10.8 versus 6.4 ± 3.7, P < 0.005). No significant associations were noted between fatigue and PA or body composition. Diets high in fibre and low in fat are associated with reduced fatigue in breast cancer survivors. The difference in fatigue for low- versus high-fibre diets exceeded the minimal clinically important difference of three units. Prospective studies evaluating the effect of changing diet on fatigue in breast cancer survivors are warranted.

A low-glycemic load diet reduces serum C-reactive protein and modestly increases adiponectin in overweight and obese adults

Low-glycemic load (GL) diets improve insulin resistance and glucose homeostasis in individuals with diabetes. Less is known about whether low-GL diets, independent of weight loss, improve the health profile for persons without diabetes or other preexisting conditions. We conducted a randomized, cross-over feeding study testing low- compared to High-GL diets on biomarkers of inflammation and adiposity in healthy adults. Eighty participants (n = 40 with BMI 18.5-24.9 kg/m²; n = 40 with BMI 28.0-40.0 kg/m²) completed two 28-d feeding periods in random order where one period was a high-GL diet (mean GL/d = 250) and the other a low-GL diet (mean GL/d = 125). Diets were isocaloric with identical macronutrient content (as percent energy). All food was provided and participants maintained weight and usual physical activity. Height, weight, and DXA were measured at study entry and weight assessed again thrice per week. Blood was drawn from fasting participants at the beginning and end of each feeding period and serum concentrations of high-sensitivity CRP, serum amyloid A, IL-6, leptin, and adiponectin were measured. Linear mixed models tested the intervention effect on the biomarkers; models were adjusted for baseline biomarker concentrations, diet sequence, feeding period, age, sex, and body fat mass. Among participants with high-body fat mass (>32.0% for males and >25.0% for females), the low-GL diet reduced CRP (P = 0.02) and marginally increased adiponectin (P = 0.06). In conclusion, carbohydrate quality, independent of energy, is important. Dietary patterns emphasizing low-GL foods may improve the inflammatory and adipokine profiles of overweight and obese individuals.

Serum amyloid A: A new potential serum marker correlated with the stage of breast cancer

Previous studies reported that serum amyloid A (SAA) is elevated in patients with tumors, including breast cancer, compared to healthy controls. In addition, the levels of SAA increase gradually with tumor progression. In this study, we investigated the blood SAA level of breast cancer patients, and evaluated its potential as a serum biomarker for the early diagnosis of breast cancer and as a staging estimate. SAA protein was determined by enzyme-linked immunosorbent assay in serum samples from 30 healthy women, 21 women with benign diseases and 118 breast cancer patients who were subdivided into 4 groups based on their clinical characteristics. SAA levels were not statistically different in stage I breast cancer patients compared with the healthy controls and benign breast disease patients. SAA concentrations had medians of 0.63 µg/ml in normal healthy women, 0.76 µg/ml in patients with benign disease (p>0.05) and 0.82 µg/ml in stage I breast cancer patients (p>0.05). By contrast, SAA values in stage Ⅱ, Ⅲ and Ⅳ patients had a significantly higher median compared to those of the healthy, benign breast diseases and stage I groups (p<0.05). Breast cancer patients with lymph node (LN) metastasis or distant metastasis were found to have significantly higher SAA concentrations than those without metastases. SAA is not a suitable marker for early breast cancer diagnosis, but its level is correlated with the stage of breast cancer. Thus, it may be a good candidate marker for the staging and prognosis of breast cancer.