Phytochemical-rich Foods Research Articles

Nutrition and Cardio-Metabolic Risk Factors: Findings from 20 Years of the Tehran Lipid and Glucose Study.

ContextGenetic and environmental factors contribute to the incidence of metabolic syndrome (MetS). This study aimed to review all findings of studies conducted in framework of the Tehran lipid and glucose study (TLGS) regarding the association of dietary factors with cardio-metabolic risk factors.Evidence AcquisitionAll English-language studies were searched using PubMed and Scopus databases from 2000 to 2017. Finally, 105 relevant papers were included in this review.ResultsWhole grains, legumes, nuts and healthy dietary patterns (DPs) reduced risk of MetS, while white rice, salty/sweet snacks increased this. The western DP had a significant interaction with APOC3, APOA1 and MC4R polymorphisms in relation to MetS. After 6.5 years of follow-up, odds of reaching menarche ≤ 12 years was significantly higher in girls with higher intakes of milk, calcium, magnesium, and phosphorous. Among children and adolescents, higher adherence to the dietary approaches to stop hypertension (DASH)-style diet decreased the risk of abdominal obesity, whereas increased adherence to the western DP could contribute to general and abdominal obesity. A three-year follow-up of adult participants showed that higher intakes of phytochemical-rich foods were inversely related to development of insulin resistance. Higher adherence to the healthy DPs was associated with the reduced risk of hyperlipidemia and hypertention. Nutrition interventions postponed rise in the prevalence of MetS. The DASH diet resulted in weight reduction compared to control diet.ConclusionsHigher adherence to healthy food choices was associated with reduced odds of MetS, abdominal obesity, dyslipidemia and hypertension. The western DP accentuated the association of polymorphisms with MetS.

Higher Intake of Phytochemical-Rich Foods is Inversely Related to Prediabetes: A Case-Control Study.

Background:Dietary phytochemical index (DPI) has introduced as an inexpensive method for quantifying the phytochemicals in foods. For the first time, this study was conducted to investigate the relationship between DPI and the risk of prediabetes.Methods:Three hundred participants were assigned to 150 prediabetics (cases) and 150 healthy (controls) groups. Anthropometric values, fasting blood glucose, and 2-h oral glucose tolerance test (OGTT) were measured. The DPI was calculated based on data collected from 168-item validated food frequency questionnaire.Results:The sex-specific energy-adjusted DPI was inversely related to fasting blood glucose (FBG) and OGTT (P < 0.001). The odds ratio (OR) of prediabetes was assessed across sex-specific energy-adjusted DPI quartiles. After adjusting for body mass index, physical activity, education, dietary intake of energy, fiber, carbohydrate (% of energy), fat (% of energy), and protein (% of energy), the OR of prediabetes across the sex-specific energy-adjusted DPI quartiles decreased significantly (P-trend < 0.001).Conclusions:We found that higher DPI score is related to lower prediabetes OR. This simple method may be used for the improvement of dietary intake to prevent prediabetes.

Phytochemical-rich foods inhibit the growth of pathogenic trichomonads

BackgroundPlants produce secondary metabolites that often possess widespread bioactivity, and are then known as phytochemicals. We previously determined that several phytochemical-rich food-derived preparations were active against pathogenic foodborne bacteria. Trichomonads produce disease (trichomoniasis) in humans and in certain animals. Trichomonads are increasingly becoming resistant to conventional modes of treatment. It is of interest to test bioactive, natural compounds for efficacy against these pathogens.MethodsUsing a cell assay, black tea, green tea, grape, pomegranate, and jujube extracts, as well as whole dried jujube were tested against three trichomonads: Trichomonas vaginalis strain G3 (found in humans), Tritrichomonas foetus strain D1 (found in cattle), and Tritrichomonas foetus-like organism strain C1 (found in cats). The most effective of the test substances was subsequently tested against two metronidazole-resistant Trichomonas vaginalis strains, and on normal mucosal flora.ResultsBlack tea extract inhibited all the tested trichomonads, but was most effective against the T. vaginalis organisms. Inhibition by black tea was correlated with the total and individual theaflavin content of the two tea extracts determined by HPLC. Metronidazole-resistant Trichomonas vaginalis strains were also inhibited by the black tea extract. The response of the organisms to the remaining preparations was variable and unique. We observed no effect of the black tea extract on common normal flora bacteria.ConclusionsThe results suggest that the black tea, and to a lesser degree green tea, grape seed, and pomegranate extracts might present possible natural alternative therapeutic agents to treat Trichomonas vaginalis infections in humans and the related trichomonad infections in animals, without negatively affecting the normal flora.

Inhibition of hazardous compound formation in muscle foods by antioxidative phytophenols.

Individual and mixed herbal extracts, as well as plant spices, are widely used in the preparation of muscle foods to enhance the organoleptic attributes. Abundantly rich in phenolic compounds, many of the phytochemical extracts have been shown to possess strong radical-scavenging and metal ion-binding properties and hence exert antioxidant activity in meat products. Because of their antiradical nature, phenolic acids and flavonoids, such as tea catechins, caffeic acid, chlorogenic acid, and mixed polyphenols derived from rosemary, licorice, and other herbal materials, are capable of inhibiting the formation of harmful secondary products from oxidized lipids and proteins. The inactivation of carcinogenic compounds produced in some nitrite-cured and high temperature-processed meats (e.g., nitrosamines and aromatic amines) by phytophenols has also been demonstrated in recent studies. Here, I describe the application of phytochemical-rich food ingredients in prepared meat and discuss the mechanisms by which plant-derived phenolic antioxidants mitigate toxicant and mutagen production in muscle foods.

Association between high consumption of phytochemical-rich foods and anthropometric measures: a systematic review

Phytochemical-rich foods consumption may be a valid nutritional strategy to reduce the risk of weight gain and obesity. The phytochemical index (PI) is a simple and nonspecific method to evaluate the phytochemical intake, defined as the percentage of dietary calories derived from foods rich in phytochemicals. We aimed to conduct a systematic review to evaluate whether high consumption of phytochemical-rich foods evaluated by the PI is associated with lower values of anthropometric measurements. The available literature suggests that the PI seems to be inversely associated with body weight and waist circumference. Analyzing the longitudinal changes in anthropometric variables, individuals with high intake of phytochemicals gained less weight and fat mass when compared to those with lower PI. Our findings suggest that higher PI is associated with lower body mass index, waist circumference and adiposity. Whether the results are a reflex of a lower calorie intake or the anti-obesity properties of phytochemicals remains to be elucidated.

Increased fruit and vegetable intake among older adults participating in Kentucky’s congregate meal site program

ABSTRACTThe purpose of this study was to determine if the amount and variety of fruits and vegetables consumed increased among community-dwelling older adults participating in Kentucky’s congregate meal site program following a series of five nutrition education lessons. A convenience sample of older adults attending senior centers (n = 35)—two intervention (n = 19) and two control (n = 16) centers—participated in this quasi-experimental pilot study. Following the intervention there was a significant increase in actual fruit and vegetable intake in the intervention group (p < .05) as assessed by platewaste measurements of the congregate lunch meal. In addition, from pre- to post-intervention, a trend towards increased self-reported intake in the variety of fruit and vegetables was observed among the intervention group. As well, a significant increase in the number of days intervention participants self-reported consuming at least 4.5 cups of fruits and vegetables in the last 7 days (2.44 ± 2.09 days to 4.28 ± 1.99 days (p = .004)) was observed; and knowledge pertaining to phytochemicals increased (p < .05). The phytochemical index (PI) score of the lunch meal, taking into account that the older adults' consumption of meal components, including phytochemical-rich foods, was 26.9. Overall, study results indicated that a short theory-based nutrition education program offered to community-dwelling older adults was linked to an increase in fruit and vegetable consumption and phytochemical knowledge.

Theobroma cacao extract attenuates the development of Dermatophagoides farinae-induced atopic dermatitis-like symptoms in NC/Nga mice

Cacao beans from Theobroma cacao are an abundant source of polyphenols, particularly flavonoids. Previous studies demonstrated that cacao flavanols decrease pro-inflammatory cytokines resulting in the alleviation of allergic symptoms. We sought to investigate the effects of cacao extract (CE) on Dermatophagoides farinae extract (DFE)-induced atopic dermatitis (AD)-like symptoms. CE attenuated DFE-induced AD-like symptoms as assessed by skin lesion analyses, dermatitis score, and skin thickness. Histopathological analysis revealed that CE suppressed DFE-induced immune cell infiltration into the skin. These observations occurred concomitantly with the downregulation of inflammatory markers including serum immunoglobulin (Ig) E, chemokine; thymus and activation-regulated chemokine and macrophage-derived chemokine as well as the skin-derived cytokines interleukin (IL)-4, IL-5, and interferon-γ. CE also significantly alleviated transepidermal water loss and increased skin hydration. These results suggest that CE, a natural phytochemical-rich food, has potential therapeutic efficacy for the treatment of AD.

Healthy Hunger-Free Kids Act Increases Phytochemicals in Menus and Curriculum Furthers Identification of Phytochemical-Rich Foods.

This study evaluated whether providing the Fruits and Vegetables (F/V) required by the Healthy Hunger-Free Kids Act (HHFKA) increased phytochemical/antioxidant content of school lunches. Additionally, the ability of adolescents to apply their nutritional knowledge following participation in a nutrition-focused science-based curriculum was assessed. Changes in antioxidant/phytochemical content from F/V offered in school lunch menus were analyzed Pre-and Post-HHFKA. Food logs completed by 717 youth aged 10-18 were analyzed for correctly identifying "fighting foods". Significant increases in antioxidant/phytochemical content resulted following implementation of HHFKA (P<0.05). Seventy-five percent [0, 100] of the time students accurately identified "fighting foods" in their one-day in-school food log (n=468). Creatively incorporating nutrition education into core curriculum, when paired with a supportive built environment that increases F/V access (HHFKA), generates a multilevel intervention promoting F/V consumption among school-aged youth.

Proteomic response of inflammatory stimulated intestinal epithelial cells to in vitro digested plums and cabbages rich in carotenoids and polyphenols.

Due to their anti-oxidant and anti-inflammatory potential, polyphenol and carotenoid-rich plant foods have been suggested as promising phytochemicals in the prevention of or as adjuvants regarding inflammatory bowel diseases (IBD). In the present study, we investigated whether plum (Italian Plum, Prunus cocomilla), or cabbage (Kale, Brassica oleracea var. sabellica), selected for their high phytochemical content, are able to reduce inflammation in cellular models of the intestinal epithelium, employing proteomic methods. For this purpose, plum/cabbage (carotenoid content: 1.9 mg per 100 g resp. 13 mg per 100 g; polyphenol content: 83 mg per 100 g resp. 27 mg per 100 g) were gastro-intestinally digested, and aliquots exposed (18 h) to either a monoculture (Caco-2) or a triple culture (Caco-2/HT-29-MTX (90 : 10, v/v) with THP-1 like macrophages), stimulated (with LPS, TNF-α, and IL-1β) to induce inflammation. Cells (Caco-2, Caco-2/HT-29-MTX, and THP-1) were then harvested separately, and proteomic analyses of total cell extracts were carried out by 2D-DIGE. In the monoculture, 68 protein-spots were significantly (p < 0.05, expression ratio >1.5) differentially regulated due to the Kale and Italian plum digesta, and in the co-culture 206 protein-spots, compared to digesta without plum/cabbage. These belonged to 27 (monoculture) and 76 (coculture) uniquely identified proteins, suggesting the coculture to be a more sensitive model. Proteins included antioxidant enzymes such as catalase, superoxide dismutase and glutathione-S-transferases. Only 3 proteins were differentially regulated in the THP-1 cells, perhaps as these were only indirectly exposed. The results show promise regarding some aspects related to IBD complications, however, employing phytochemical-rich food items should be further investigated in in vivo trials.

Dietary phytochemical index and the risk of insulin resistance and β-cell dysfunction: a prospective approach in Tehran lipid and glucose study

Background: In this study, we aimed to investigate the association of dietary phytochemical index (DPI) with insulin resistance, β-cell dysfunction, and insulin sensitivity. Methods: This longitudinal study was conducted on 1141 participants of the Tehran Lipid and Glucose Study. Dietary data were collected using a validated semi-quantitative FFQ with 168 food items at baseline and DPI was calculated. Fasting serum insulin and glucose were measured at baseline and again after a 3-year of follow-up. Results: After 3-years of follow-up, the risk of hyperinsulinemia significantly decreased by 65 (OR = 0.35, 95% CI = 0.21–0.60) and 86% (OR = 0.14, 0.07–0.29), in the third and fourth quartile categories of DPI, respectively. The occurrence of insulin resistance and insulin insensitivity in participants with higher DPI was significantly lower than the others (OR = 0.48, 95% CI = 0.25–0.93 and OR = 0.11, 95% CI = 0.05–0.24, respectively). Conclusion: Higher consumption of phytochemical-rich foods may have protective effects against development of insulin resistance.

Dietary phytochemical index is inversely associated with the occurrence of hypertension in adults: a 3-year follow-up (the Tehran Lipid and Glucose Study).

The epidemiological association of phytochemical-rich foods with the risk of hypertension is unclear. This study aimed to determine the association of dietary phytochemical index (PI) with the occurrence of hypertension (HTN) after 3 years of follow-up in Tehranian adults. This prospective study was conducted on 1546 nonhypertensive subjects, aged 20-70 years. Dietary intake was collected by validated semiquantitative food frequency questionnaire (FFQ). Dietary PI was calculated as (dietary energy derived from phytochemical-rich foods (kcal)/total daily energy intake (kcal)) × 100. Blood pressure was measured at baseline and after 3 years of follow-up and HTN was defined by Joint National Committee on prevention, detection, evaluation and treatment of high blood pressure criteria. The odds of HTN after 3 years in each quartile category of dietary PI were estimated by logistic regression model and adjusted for potential variables. The mean age of participants was 38.0±12.0 years and 43% were male. The mean dietary PI was 29.1±11.8. After 3 years of follow-up, 265 (17.1%) new cases of HTN were identified. No significant changes were observed in the systolic and diastolic blood pressure across quartile categories of dietary PI. After adjustment for confounders, the odds (95% confidence interval) of HTN across quartiles of dietary PI were 1.00, 0.97 (0.62-1.38), 0.69 (0.45-1.07) and 0.52 (0.32-0.84) (P for trend=0.004). Consumption of phytochemical-rich foods may prevent the development of HTN. Further investigations are, however, recommended.

Dietary Intake, Changes in Lipid Parameters and the Risk of Hypertriglyceridemia: A Prospective Approach in the Tehran Lipid and Glucose Study.

This study assessed the association of dietary factors with 3-year changes in serum triglycerides (TG), HDL-C and the atherogenic index of plasma (AIP) among Iranian adults. This longitudinal study was conducted with 1938 adults. Demographics, anthropometrics and biochemical measurements, including serum (TG) and HDL-C and AIP, were assessed at baseline (2006 - 2008) and after a 3 year follow-up (2009 - 2011). Dietary data was collected using a validated food frequency questionnaire at baseline. The associations of dietary factors with 3-year changes in lipid parameters were evaluated using linear regression models and the incidence of hypertriglyceridemia after 3 years was assessed using logistic regression models with adjustment for potential confounders. The mean age of the participants at baseline was 41.0 ± 13.0 years. Dietary energy density was negatively associated with HDL-C and positively associated with AIP changes (P < 0.05). A three-year change of serum TG was inversely related to energy intake from phytochemical rich foods, whole grains, and legumes (P < 0.05). Fast food intake was positively related to serum TG and AIP changes. Higher compared to lower intakes of dietary fiber and phytochemical-rich foods had similar impacts on a decreased risk of hypertriglyceridemia (OR = 0.58, 95 % CI = 0.34 - 1.00). Higher - compared to lower - dietary sodium to potassium ratios (Na/K ratio) increased the risk of hypertriglyceridemia by 63 % (OR = 0.1.63, 95 % CI = 0.34 - 1.00). These findings suggested that more dense diets, and a higher intake of fast food and fat, could have undesirable effects on lipid and lipoprotein levels; in contrast, higher intakes of fiber, and phytochemical rich foods, especially whole grain and legumes, could have protective effects against undesirable changes in lipid and lipid profiles.

Diet pattern and longevity: do simple rules suffice? A commentary

Nutritionism reduces dietary advice to statements about a few nutrients, with sometimes unintended implications for science, industry, and the public. Although reductionist questions about nutrition are legitimate scientifically, a nutrient focus in the public arena forces the food industry to compete with the use of nutrient statements. Consumers must interpret information that may not be correct or relevant. The theory of food synergy, which postulates that the many constituents of individual foods and dietary patterns act together on health, leads to the idea that dietary policy would be clearer if it focused on foods. To illustrate this method, the food-based A Priori Diet Quality Score was described in the Iowa Women's Health Study; a substantial total mortality reduction for increasing quartiles of the score was found. The simple food-based rules implied in this a priori score support minimizing meat, salt, added sugar, and heavily processed foods while emphasizing phytochemical-rich foods. These principles could help improve nutrition policy, help industry to supply better food, and help to focus future scientific research. Although an understanding of what foods are best for health is a step forward in nutrition, other major challenges remain, including getting high-quality food to the masses and food sustainability.

Fast food consumption and the risk of metabolic syndrome after 3-years of follow-up: Tehran Lipid and Glucose Study

There are growing concern globally regarding fast food consumption and its related cardiometabolic outcomes. In this study we investigated whether fast food consumption could affect the occurrence of metabolic syndrome (MetS) after 3-years of follow-up in adults. This longitudinal study was conducted in the framework of Tehran Lipid and Glucose Study on 1476 adults, aged 19-70 y. The usual intakes of participants were measured using a validated semi-quantitative food frequency questionnaire at baseline. Biochemical and anthropometric measurements were assessed at baseline (2006-2008) and 3 years later (2009-2011). Multiple logistic regression models were used to estimate the occurrence of the MetS in each quartile of fast food consumption. The mean age of participants was 37.8±12.3 y, and mean BMI was 26.0±4.5 kg/m(2) at baseline. Participants in the highest quartile of fast food consumption were younger (33.7 vs 43.4 years, P<0.01). Higher consumption of fast food was accompanied with more increase in serum triglyceride levels and triglyceride to HDL-C ratio after the 3-year follow-up. After adjustment for all potential confounding variables, the risk of metabolic syndrome, in the highest quartile of fast foods compared with the lowest, was 1.85 (95% CI=1.17-2.95). The effects of fast food consumption on the occurrence of MetS were more pronounced in younger adults (<30 years), and participants who had greater wait to hip ratio, consumed less phytochemical-rich foods or had low-fiber diet (P<0.05). We demonstrated that higher consumption of fast foods had undesirable effects on metabolic syndrome after 3-years of follow-up in Iranian adults.

Dietary Phytochemical Index and the Risk of Breast Cancer: A Case Control Study in a Population of Iranian Women

In this study we assessed the dietary phytochemical index in relation to the risk of breast cancer in women. This case-control study was conducted on 100 incident breast cancer cases and 175 healthy controls. Data regarding socio-demographic factors, medical history, medications, and anthropometric measurements were collected. Dietary data were obtained using a validated food frequency questionnaire and a energy-adjusted dietary phytochemical index (PI) was calculated. The odds ratios of breast cancer were assessed across energy- adjusted PI quartile categories. The mean age of participants was 46.2±8.9 and 45.9±9.4 years in cases and controls, respectively. The mean PI across quartile categories was 13.9±2.6, 21.1±1.8, 26.7±2.1, 41.6±10.2 in the first, second, third and fourth quartiles, respectively. After adjustment for all potential confounders, the risk of breast cancer in the forth quartile of dietary PI was significantly decreased (OR=0.08, 95%CI=0.01-0.84). Higher intake of phytochemical-rich foods is associated with lower risk of breast cancer.

Obesity-Associated Oxidative Stress: Strategies Finalized to Improve Redox State

Obesity represents a major risk factor for a plethora of severe diseases, including diabetes, cardiovascular disease, non-alcoholic fatty liver disease, and cancer. It is often accompanied by an increased risk of mortality and, in the case of non-fatal health problems, the quality of life is impaired because of associated conditions, including sleep apnea, respiratory problems, osteoarthritis, and infertility. Recent evidence suggests that oxidative stress may be the mechanistic link between obesity and related complications. In obese patients, antioxidant defenses are lower than normal weight counterparts and their levels inversely correlate with central adiposity; obesity is also characterized by enhanced levels of reactive oxygen or nitrogen species. Inadequacy of antioxidant defenses probably relies on different factors: obese individuals may have a lower intake of antioxidant- and phytochemical-rich foods, such as fruits, vegetables, and legumes; otherwise, consumption of antioxidant nutrients is normal, but obese individuals may have an increased utilization of these molecules, likewise to that reported in diabetic patients and smokers. Also inadequate physical activity may account for a decreased antioxidant state. In this review, we describe current concepts in the meaning of obesity as a state of chronic oxidative stress and the potential interventions to improve redox balance.

The association of dietary phytochemical index and cardiometabolic risk factors in adults: Tehran Lipid and Glucose Study

Phytochemicals are natural non-nutritive bioactive compounds found in fruits, vegetables, whole grains, nuts and legumes, as well as other plant foods. In the present study, we assessed the dietary phytochemical index (PI) in relation to cardiometabolic risk factors among Iranian adults. This cross-sectional study was conducted within the framework of third phase of Tehran Lipid and Glucose Study 2006-2008. For the present study, 2567 subjects aged 19-70 years (1129 men and 1438 women) were selected randomly. Dietary data were collected using a validated semi-quantitative food frequency questionnaire with 168 food items. The PI was calculated based on daily energy derived from phytochemical-rich foods. The odds ratios of abdominal obesity, impaired fasting glucose, hypertriglyceridaemia, low high-density lipoprotein-cholesterol and hypertension were assessed across PI quartile categories. The mean (SD) age of participants was 39.4(13.2)years. Participants in the upper quartile of PI were older, and had a lower weight and waist circumference. The mean (SD) of the PI was 17.3 (5.6), 25.5 (6.4), 32.7 (8.3) and 42.8 (10.5) in the first, second, third and fourth quartiles, respectively. Compared with those in the lower quartile of PI, participants in the upper quartiles had a 66% lower risk of abdominal obesity [95% confidence interval (CI)=0.23-0.51] and a 36% lower risk of hypertriglyceridaemia (95% CI, 0.47-0.86), after adjustment for potential confounders. Higher intakes of phytochemical-rich foods are associated with a lower risk of abdominal obesity and hypertriglyceridaemia as the main cardiometabolic risk factors.

Diet-relevant phytochemical intake affects the cardiac AhR and nrf2 transcriptome and reduces heart failure in hypertensive rats

Intake of phytochemical-rich diets is inversely related to hypertension. Phytochemicals alter in vitro aryl hydrocarbon receptor (AhR) and NF-E2 related factor (nrf2) transcription factor activity and related genes pertinent to antioxidant defense. However, it is unknown if these molecular effects occur in the heart with dietary intake of physiologically relevant phytochemicals and if this correlates with reduced hypertension-associated heart failure. This extended feeding study used whole grapes as a model of a phytochemical-rich food and hypertensive heart failure-prone rats to assess mechanisms of effect. Grape intake reduced cardiac hypertrophy and fibrosis and improved diastolic function. At the development of diastolic dysfunction, hypertensive rats show reduced AhR activity, reduced expression of AhR-regulated genes, reduced glutathione and reduced activity of glutathione-regulating proteins. However, grape intake significantly increased cardiac AhR and nrf2 activity, Phase I/II gene transcripts and protein activity related to antioxidant defense. Heart failure is the leading cause of morbidity and mortality in the aged and the intake of phytochemicals from fruits and vegetables decreases with age. Concentrated antioxidant nutrient trials have failed to affect heart failure. However, this study demonstrates that diet-relevant intake of non-nutrient phytochemicals significantly reduces heart failure progression. Therefore, this study suggests that higher intake of phytochemical-containing foods may achieve cardiac benefits that isolated antioxidant supplements may not. In summary, intake of diet-relevant phytochemicals altered the cardiac antioxidant transcriptome, antioxidant defense, oxidative damage and fibrosis. Regular phytochemical intake may therefore increase cardiac resistance to cardiac pathology instigated by prolonged hypertension.

Association between dietary phytochemical index and 3-year changes in weight, waist circumference and body adiposity index in adults: Tehran Lipid and Glucose study

BackgroundHigh intakes of phytochemical-rich foods have favorable effects on the prevention of chronic diseases. In this study we assessed the dietary phytochemical index (PI) in relation to 3-year change in weight, waist circumference (WC), body adiposity index (BAI) among Tehranian adults.MethodsThis longitudinal study was conducted in the framework of Tehran Lipid and Glucose Study, between 2006–2008 and 2009–2011, on 1938 adults, aged 19–70 y. The usual intake of participants was measured at baseline using a validated semi-quantitative food frequency questionnaire and dietary PI was calculated. Anthropometric measures were assessed both at baseline and 3 years later. Multiple regression models were used to estimate mean difference changes in anthropometrics associated with various dietary PI.ResultsThe mean age of participants was 40.4 ± 13.0 y, at baseline, respectively. Mean weight gain was 1.49 ± 5.06 kg (1.65 ± 5.3 kg in men and 1.34 ± 4.9 kg in women) during 3-year period. After adjustment for potential confounding variables including age at baseline, sex, BMI, educational levels, smoking, physical activity, total energy intake, dietary intake of carbohydrate, fat and protein, dietary intakes of whole grains in the highest quartile category of PI were inversely associated with 3-year changes in weight and WC (P for trend <0.05). Dietary intake of fruits in the highest quartile was also associated with lower weight gain during the study period (P for trend <0.05). There was significant inverse association between the highest quartile category of dietary PI with the 3-year changes in weight and BAI (P for trend <0.05).ConclusionHigher dietary PI could have favorable effects on prevention of weight gain and reduction of body adiposity in adults.

Phytochemicals and Cancer Risk

A number of epidemiological studies have investigated associations between various phytochemicals and cancer risk. Phytoestrogens and carotenoids are the two most commonly studied classes of phytochemicals; phytosterols, isothiocyanates, and chlorophyll also have been investigated, although to a much lesser extent. Because there have been no systematic reviews of the literature on all phytochemicals and cancer risk to date, this article systematically reviews 96 published epidemiological studies that examined associations between phytochemicals and cancer risk. Most studies found null associations between individual phytochemicals and cancer risk at various sites. In addition, results from past studies have been largely inconsistent, and observed associations have been of relatively modest magnitude. The most consistent protective effects were observed for higher levels--dietary intake, serum, plasma, or urinary metabolites--of β-carotene and renal cell cancer, β-cryptoxanthin and lung cancer, isothiocyanates and lung cancer, isothiocyanates and gastrointestinal cancer, lignans and postmenopausal breast cancer, and flavonoids and lung cancer. Although elevated risk of certain cancers with higher levels of certain phytochemicals was observed, an insufficient pool of studies examining the same associations or inconsistent findings across studies limit the ability to conclude that any one phytochemical increases cancer risk. Additional research is needed to support previously identified associations in cases where only one study has examined a particular relationship. Importantly, continued research efforts are needed to evaluate the cumulative and interactive effects of numerous phytochemicals and phytochemical-rich foods on cancer risk.