Diet and health: what should we eat?

Health benefits of fruit and vegetables are from additive and synergistic combinations of phytochemicals

Cardiovascular disease and cancer are ranked as the first and second leading causes of death in the United States and in most industrialized countries. Regular consumption of fruit and vegetables is associated with reduced risks of cancer, cardiovascular disease, stroke, Alzheimer disease, cataracts, and some of the functional declines associated with aging. Prevention is a more effective strategy than is treatment of chronic diseases. Functional foods that contain significant amounts of bioactive components may provide desirable health benefits beyond basic nutrition and play important roles in the prevention of chronic diseases. The key question is whether a purified phytochemical has the same health benefit as does the whole food or mixture of foods in which the phytochemical is present. Our group found, for example, that the vitamin C in apples with skin accounts for only 0.4% of the total antioxidant activity, suggesting that most of the antioxidant activity of fruit and vegetables may come from phenolics and flavonoids in apples. We propose that the additive and synergistic effects of phytochemicals in fruit and vegetables are responsible for their potent antioxidant and anticancer activities, and that the benefit of a diet rich in fruit and vegetables is attributed to the complex mixture of phytochemicals present in whole foods.

Hibiscus sabdariffa extract inhibits the development of atherosclerosis in cholesterol-fed rabbits

Hibiscus sabdariffa L., a local soft drink material and medicinal herb, is usually used effectively in native medicines against hypertension, pyrexia, and liver disorders. Here, we report an extract, HSE (H. sabdariffa extract), which is designed to exhibit hypolipidemia and antiatherosclerotic effects in rabbits with experimental atherosclerosis. New Zealand White rabbits were fed with a normal diet, high cholesterol (1.3%), lard oil (3%) diet (HCD) with or without 0.5 or 1% HSE for 10 weeks. The levels of triglyceride, cholesterol, and low-density lipoprotein cholesterol (LDL-C) were lower in the serum of rabbits fed HCD plus HSE than in the serum of rabbits fed HCD. Feeding HSE (0.5 and 1% in the diet) to rabbits significantly reduced severe atherosclerosis in the aorta. Histopathological examination showed that HSE reduced foam cell formation and inhibited smooth muscle cell migration and calcification in the blood vessel of rabbits. These results suggest that HSE inhibits serum lipids and shows an antiatherosclerotic activity.

A high-score Mediterranean dietary pattern is associated with a reduced risk of peripheral arterial disease in Italian patients with Type 2 diabetes

BACKGROUND

The 'Mediterranean diet' is considered to exert protective effects on cardiovascular disease, although a wide range of dietary patterns exists among subjects living even in the same Mediterranean country.

OBJECTIVE

To investigate the association between specific dietary patterns and peripheral arterial disease (PAD) in Italian Type 2 diabetes patients.

DESIGN

From a cohort of 944 patients with Type 2 diabetes, 144 patients with PAD were selected, and matched for age and sex with 288 Type 2 diabetic control patients without macrovascular complications. A dietary score was elaborated from a semiquantitative food frequency questionnaire. The higher the final score, the healthier the eating habit.

RESULTS

In multivariate analysis, a higher score was independently associated with a significant reduction in PAD risk [odds ratio (OR) = 0.44; 95% confidence interval (CI) 0.24, 0.83]. Diabetes duration (OR > 15 years = 2.49; 95% CI 1.45, 4.25), hypertension (OR = 2.12; 95% CI 1.31, 3.45) and butter consumption (OR = 2.6; 95% CI 1.15, 3.68) were also significantly associated with PAD. The dietary score significantly improved the predictive value of models based on duration of diabetes and hypertension. (LSR = 2.19, DF = 7, P < 0.001). The effect of a high dietary score on the risk of PAD was independent of diabetes duration and hypertension.

CONCLUSION

In Italian Type 2 diabetics, a higher dietary score has a protective role against PAD. The use of butter increases the risk of PAD even in patients regularly consuming olive oil. Dietary advice may be helpful for the prevention of PAD in diabetics even in populations traditionally accustomed to a Mediterranean dietary habit.

Association between fruit and vegetable intake and change in body mass index among a large sample of children and adolescents in the United States

OBJECTIVE

To assess whether intake of fruits and vegetables was associated with change in body mass index (BMI) among a large sample of children and adolescents in the United States.

DESIGN

Prospective cohort study of children and adolescent who were 9-14 y of age in 1996, when the study began.

SUBJECTS

The subjects included 8203 girls and 6715 boys in an ongoing cohort study who completed at least two questionnaires between 1996 and 1999.

MEASUREMENTS

Fruit and vegetable intake was assessed in 1996-1998 with a validated food frequency questionnaire designed specifically for children and adolescents. The outcome measure was change in age- and gender-specific z-score of BMI (kg/m(2)). Self-reported weight and height, which were used to calculate BMI, were collected annually from 1996 to 1999.

RESULTS

During 3 years of follow-up, annual changes in BMI were slightly greater among the boys than the girls. After controlling for Tanner stage of development, age, height change, activity and inactivity, which are known or suspected predictors of change in BMI, among the girls there was no relation between intake of fruits, fruit juice, or vegetables (alone or combined) and subsequent changes in BMI z-score. Among the boys, intake of fruit and fruit juice was not predictive of changes in BMI, however, vegetables intake was inversely related to changes in BMI z-score (beta per serving=-0.003). However, after adjusting for caloric intake, the magnitude of the effect was diminished and no longer significant.

CONCLUSION

Our results suggest that the recommendation for consumption of fruits and vegetables may be well founded, but should not be based on a beneficial effect on weight regulation.

[Dietary habits and food consumption in Spanish children and adolescents (1998-2000): socioeconomic and demographic factors]

BACKGROUND AND OBJECTIVE

Although children and adolescents have special nutritional requirements due to their physical development, little is known about the concept of a healthy diet. This study shows the food consumption of the Spanish population aged 2-24 years in relation to socio-economic and geographic factors.

SUBJECTS AND METHOD

A representative sample of the Spanish population (n = 3.534 individuals, 1.905 female and 1.629 male) was studied. Both a 24-hours recall and a general questionnaire with socio-economic, demographic and life style items were administered.

RESULTS

Most individuals consumed meals at home. The consumption of vegetables (90.4 g), cereals (181.1 g) and potatoes (69.7 g) was low, the consumption of red meat (71.6 g) and sausages (46.8 g) was high, and fish consumption was low (47.7 g). Girls had insufficient intakes of milk (280.9 g). We noticed geographical differences in food consumption which may be reflected in various health outcomes in adulthood. The familiar socioeconomic status and the educational level of the mother showed some influence on the intakes of meat, fish, fruits and vegetables, yoghurt and cheese.

CONCLUSIONS

Nutritional education programs are needed to settle the observed nutritional inadequacies in the food habits of Spanish children and adolescents so that the future health of the population improves. It is also needed to reduce the inequalities linked to geographic and socio-economic factors.

Simultaneous identification of soyasaponins and isoflavones and quantification of soyasaponin Bb in soy products, using liquid chromatography/electrospray ionization-mass spectrometry

A method has been developed for simultaneous identification of soyasaponins and soy isoflavones in soy products, based on liquid chromatography/electrospray ionization-mass spectrometry (LC/ESI-MS). Soy-based nutraceutical products were analyzed by LC/ESI-MS with detection of protonated and sodiated molecular ions, as well as characteristic fragment ions for these compounds. Soy isoflavones were characterized by a strong protonated molecular ion in addition to corresponding [aglycone + H](+) ions. Monitoring the soyasaponin-specific protonated aglycone and dehydrated aglycone ions throughout the chromatogram provided a unique fingerprint for soyasaponin content in the samples. This mass spectrometric fingerprint also allowed immediate classification of the soyasaponin analytes as group A or B soyasaponins, based on the unique masses of aglycone ions observed for each class. Quantification of soyasaponin B(b) in soy-derived materials, based on the use of a purified soyasaponin B(b) standard and a glycyrrhizin internal standard, has been accomplished.

Nutritional issues for adolescents

This chapter provides background on the nutritional health of adolescents, focusing on a public health or population-level approach. We detail some specific nutritional issues and related health outcomes that are particularly relevant to adolescents, including overweight and obesity, type 2 diabetes, eating-related disorders and bone health as it relates to calcium intake. We discuss implications of the trends in adolescent dietary habits for practitioners and propose a research agenda for better understanding and positively influencing future adolescent nutritional health.

Understanding nutrition communication between health professionals and consumers: development of a model for nutrition awareness based on qualitative consumer research

BACKGROUND

Consumers have been exposed to nutrition information from a variety of sources, including the family doctor. They are often not aware of their own risk behavior regarding nutrition.

OBJECTIVE

This study sought to assess food associations, conversation topics, interest in food topics, and use of information sources by means of qualitative consumer research. Another aim was to provide a hypothetical model for nutrition awareness that could be tested in a quantitative survey.

DESIGN

Three focus groups with 30 Dutch consumers altogether were carried out. Qualitative data were analyzed with the computer software program NUD*IST (QSR, Melbourne) by sorting text blocks into categories, and new themes emerged. In addition, a hypothetical model for nutrition awareness was developed.

RESULTS

Consumers associated food most often with safe food, and food safety was the topic most often discussed. Tasty food was the most important food conversation topic. The family doctor was the information source most talked about. Furthermore, consumers possibly lacked some nutrition awareness.

CONCLUSIONS

Careful analysis revealed new themes (new in the past 10 y), such as concerns about food safety and reconsideration of the roles of family doctors and dietitians. Based on these themes, recommendations for nutrition communication were composed.

Feedback strategies to raise awareness of personal dietary intake: results of a randomized controlled trial

BACKGROUND

Feedback is a strategy that can be used to influence awareness of dietary habits. Feedback was applied in an interactive computer-tailored intervention and in printed self-test forms.

METHODS

A randomized controlled trial with a 3 (study groups) x 2 (higher vs. medium or lower educational level) design was conducted. Adult subjects (N = 304) were randomly assigned to a feedback group or the control group. Immediate impact on realism of self-rated intake levels of fat, fruit, and vegetables were tested, as were intentions to change.

RESULTS

Self-rated fat intake compared to others was more realistic among respondents with a medium or lower educational level in the tailored intervention group. Self-rated fruit intake compared to others was more realistic in the tailored intervention group. Self-rated fat intake was more realistic in the tailored intervention than the self-test group. Intention to reduce fat consumption was greater in the tailored intervention group. Intention to eat more vegetables was greater in the tailored than in the self-test group. Subjects rated the tailored intervention as more effective, more personally relevant, more individualized, and providing more new information.

CONCLUSIONS

Only the tailored intervention had an immediate impact on awareness and dietary change intention and was appreciated better than both other interventions.

Buckwheat honey increases serum antioxidant capacity in humans

Honey has been known to exert significant in vitro antioxidant activity, in part due to its phenolic content. However, conclusions that the antioxidants in honey are or are not efficacious in the human body cannot be reached if its antioxidant action is not assessed as part of a human study. In the present study, the acute effect of consumption of 500 mL of water, water with buckwheat honey, black tea, black tea with sugar, or black tea with buckwheat honey on serum oxidative reactions was examined in 25 healthy men. Antioxidant capacity of human serum samples was measured using different methods: the oxygen radical absorbance capacity (ORAC) assay, ex vivo susceptibility of serum lipoprotein to Cu(2+)-induced oxidation, and the thiobarbituric acid reactive substances (TBARS) assay. The results showed that the serum antioxidant capacity determined by ORAC increased significantly (p < 0.05) by 7% following consumption of buckwheat honey in water. No significant changes in serum antioxidant capacity could be established after the consumption of any of the other beverages. Ex vivo serum lipoprotein oxidation and TBARS values were not significantly altered after consumption of any of the five beverages. This study provides primary evidence of the in vivo antioxidant activity of buckwheat honey. However, long-term studies and epidemiological data are necessary to investigate whether honey consumption can exert overall antioxidant-related health benefits.

Nutrition, diet, physical activity, smoking, and longevity: from primitive hunter-gatherer to present passive consumer--how far can we go?

In millennia past, and until recently, among hunter-gatherers and like populations, in all populations, in measure, down through the ages, the securing of sufficient food was life's primary purpose. Virtually all people were physically very active during early life and later in their everyday occupations. In contrast, nowadays, in Western populations, with relative abundance of food, the way of life is mainly one of enjoyment of meals, of work, and of leisure time, in a context of as few as one child per family, and with long survival times of about 75 to 80 y, due in large part to much reduced child mortality and the effective treatments of disorders and diseases. As to changes in food consumption, compared with the erratic and often monotonous fares of the past, both far and not so distant, everyday diets have changed tremendously in variety, nutritional value, and palatability such that, inter alia, overeating is almost inevitable. Compounding the latter, sedentariness is the rule, in contrast to the previously very high level of everyday physical activity in the masses of populations. In consequence, one speculation is that, by 2230, "all Americans will be obese." Although the living of much longer lives is highly gratifying, understandably, all wish to have longer "healthy life expectancy," i.e. to suffer as little as possible before death. However, with regard to the present-day "passive consumer," although the practical recommendations for leading still healthier lives, dietarily and non-dietarily, are well known, very few are interested, and still fewer practice them. Nevertheless, for the few who, with determination, are eager to improve their lifestyles, there could be highly profitable lengthening of years of "healthy life expectancy" by eating less, eating more plant foods, being much more physically active, and restricting non-dietary risk factors (smoking, alcohol consumption).

Gender, age, socio-demographic and lifestyle factors associated with major dietary patterns in the Spanish Project SUN (Seguimiento Universidad de Navarra)

OBJECTIVE

To ascertain the major dietary patterns in the cohort 'SUN' and to assess the association of several sociodemographic (including age and gender) and lifestyle variables with the adherence to these dietary patterns.

DESIGN

This study is a cross-sectional analysis of 3847 subjects (1587 men and 2260 women) belonging to a prospective cohort study based on self-reported questionnaires. A factor analysis based on 30 predefined food groups was conducted to ascertain the major dietary patterns in the cohort. Multiple regression models were fitted to assess the relationship between several sociodemographic and lifestyle variables and the adherence to these dietary patterns (measured using two scores with observed values ranging from -3.2 to +4.6 for the Western pattern and -3.1 to +5.5 for the Mediterranean pattern).

RESULTS

Two major dietary patterns were found. The first pattern was labelled as a 'Western' dietary pattern and the other as a 'Spanish-Mediterranean' dietary pattern. Younger subjects were more likely to follow a 'Western' dietary pattern; the coefficient representing the change for every 10 y increase in age was b=-0.24 (P<0.001) for men and b=-0.12 (P<0.001) for women. More physically active subjects were less likely to follow a 'Western' dietary pattern and more likely to follow a 'Spanish-Mediterranean' dietary pattern.

CONCLUSIONS

An association between a higher level of physical activity during leisure time and adherence to a 'Spanish-Mediterranean' diet was apparent. However, the profile of being a young, sedentary and single male was identified as the most likely to exhibit a departure from the traditional 'Spanish-Mediterranean' diet and follow a 'Western' dietary pattern.

Plasma retinol and tocopherol levels in relation to demographic, lifestyle and nutritional factors of plant origin in Greece

In the context of the Greek segment of the European Prospective Investigation into Cancer and Nutrition (EPIC) we have conducted a cross-sectional study to determine the effect of demographic, lifestyle and nutritional factors of plant origin on retinol, alpha-tocopherol and gamma-tocopherol. Study subjects were a random sample of forty-five men and sixty-eight women, aged 30-82 years, from the Greek EPIC cohort of 27953 volunteers. Analyses were done using linear regression models with the vitamin blood levels as dependent variables, and BMI, the intake of selected food items, total energy intake and a set of demographic factors as independent variables. Women had significantly lower plasma retinol levels (P<0.006) than men. Both alpha- and gamma-tocopherol levels increased by approximately 5 % for every additional 5 years of age. Among dietary factors, intake of non-fruity vegetables was associated with increase, while intake of added lipids other than olive oil with decrease, of plasma retinol levels. BMI was positively associated with plasma gamma-tocopherol only, while none of the foods or food groups investigated significantly affected the plasma levels of either of the two tocopherols. These findings need to be confirmed before attempts are made to use them in the context of explanatory mechanistic processes.

Diet quality and major chronic disease risk in men and women: moving toward improved dietary guidance

BACKGROUND

Adherence to the Dietary Guidelines for Americans, measured with the US Department of Agriculture Healthy Eating Index (HEI), was associated with only a small reduction in major chronic disease risk. Research suggests that greater reductions in risk are possible with more specific guidance.

OBJECTIVE

We evaluated whether 2 alternate measures of diet quality, the Alternate Healthy Eating Index (AHEI) and the Recommended Food Score (RFS), would predict chronic disease risk reduction more effectively than did the HEI.

DESIGN

A total of 38 615 men from the Health Professional's Follow-up Study and 67 271 women from the Nurses' Health Study completed dietary questionnaires. Major chronic disease was defined as the initial occurrence of cardiovascular disease (CVD), cancer, or nontraumatic death during 8-12 y of follow-up.

RESULTS

High AHEI scores were associated with significant reductions in risk of major chronic disease in men [multivariate relative risk (RR): 0.80; 95% CI: 0.71, 0.91] and in women (RR: 0.89; 95% CI: 0.82, 0.96) when comparing the highest and lowest quintiles. Reductions in risk were particularly strong for CVD in men (RR: 0.61; 95% CI: 0.49, 0.75) and in women (RR: 0.72; 95% CI: 0.60, 0.86). In men but not in women, the RFS predicted risk of major chronic disease (RR: 0.93; 95% CI: 0.83, 1.04) and CVD (RR: 0.77; 95% CI: 0.64, 0.93).

CONCLUSIONS

The AHEI predicted chronic disease risk better than did the RFS (or the HEI, in our previous research) primarily because of a strong inverse association with CVD. Dietary guidelines can be improved by providing more specific and comprehensive advice.

Nutrition as a mediator in the relation between oral and systemic disease: associations between specific measures of adult oral health and nutrition outcomes

Recent associations between oral health and systemic disease have led to renewed interest in the mouth and its contribution to health outcomes. Many pathways for this relationship have been postulated, among them the potential mediating role of nutrition. The link between various nutrients and systemic disease has been established, but relatively little work has been done in relating oral conditions with nutrition. We searched MEDLINE, from 1966 to July, 2001, to identify articles relating specific oral measures to nutrition outcomes. We included original articles written in English with a sample size greater than 30 that used objective oral health measures. We reviewed a total of 56 articles. Only a small proportion of these studies were methodologically sound. Although many studies were small and cross-sectional, the literature suggests that tooth loss affects dietary quality and nutrient intake in a manner that may increase the risk for several systemic diseases. The impact of tooth loss on diet may be only partially compensated for by prostheses. To date, there is little information relating periodontal disease and oral pain and nutrition. A few studies suggest poorer nutrition among individuals with xerostomia and altered taste. Further, impaired dentition may contribute to weight change, depending on age and other population characteristics. There is a paucity of well-designed studies addressing oral health and nutrition. Before we can acquire a better understanding of how nutrition and oral health interrelate, however, more studies will be required to confirm these associations-preferably longitudinal studies with larger sample sizes and better control of important confounders.

Persistent oxidative stress in colorectal carcinoma patients

We examine whether the level of 8-oxo-2'-deoxyguanosine (8-oxodGuo) in lymphocytes DNA is higher in colon cancer when compared to the control group. Factors that may influence oxidative stress such as antioxidant vitamins and uric acid were also determined. Blood samples were obtained from a control group of 55 healthy persons and 43 colon cancers. 8-OxodGuo level and the vitamins concentration were measured by high-performance liquid chromatography. The levels of 8-oxodGuo were significantly higher whereas the concentrations of the vitamins and uric acid were significantly lower in colon cancer patients than in control group. Therefore, the decreased concentration of antioxidant vitamins together with lower amount of uric acid may be responsible for the formation of pro-oxidative environment in blood of colorectal carcinoma patients.

Cancer of the oesophagus in Africans in sub-Saharan Africa: any hopes for its control?

Oesophageal cancer, a highly lethal tumour, occurs to a variable extent in Africans in sub-Saharan African countries. In many, its incidence remains low, as in the Ivory Coast, Mali and the Gambia. However, in other African countries, the incidence rate has risen considerably, especially in city populations, as in Durban, South Africa, in Kyadondo, Uganda, and in Harare, Zimbabwe, rising to levels far higher than those reported in white populations. As to risk factors, in some African settings, smoking is a factor, and in others, alcohol consumption. Nutritionally, one enquiry, made in Durban, indicated the use of less-refined cereal products, with higher consumptions of vegetables and fruit, to be protective. In developed populations, protective factors are considered to be those characteristic of a "prudent" lifestyle. However, known risk factors largely fail to explain the high variability in the disease's occurrence. In seeking to combat the disease, it is thought unlikely that most Africans, especially urban dwellers, are willing to alter their lifestyle appropriately, even with the understanding that the changes would confer other protective benefits. This suggests that further rises, especially in the contexts of high incidence rates, are inevitable.

Frequent intake of tropical fruits that are rich in beta-cryptoxanthin is associated with higher plasma beta-cryptoxanthin concentrations in Costa Rican adolescents

Dietary tocopherols and carotenoids may play a role in preventing cancer and cardiovascular diseases. Because these may begin to develop during adolescence, dietary patterns during this period could influence long-term risk. The objective of this study was to examine the intake and plasma concentrations of the major carotenoids and tocopherols in 159 adolescents (mean +/- SD, 15.5 +/- 2.5 y old) living in Costa Rica. All participants completed a 135-item food-frequency questionnaire and provided a fasting blood sample. Carotenoid and tocopherol intakes were adjusted for total energy and plasma concentrations for total cholesterol. The relative abundance of carotenoids in the diet was similar to their distribution in plasma; lycopene was the most abundant, followed by beta-carotene and lutein + zeaxanthin. gamma-Tocopherol was more abundant than alpha-tocopherol in the diet, but alpha-tocopherol was approximately sevenfold higher in plasma. The highest diet-plasma correlations (adjusted for age, sex and body mass index) were 0.38 for beta-cryptoxanthin, 0.33 for gamma-tocopherol and 0.17 for lutein + zeaxanthin (all P < 0.05). All other correlations were r < 0.15. Papaya intake was the best food predictor of plasma beta-cryptoxanthin concentrations (r = 0.41). Subjects that frequently (> or =3/d) consumed tropical fruits with at least 50 micro g/100 g beta-cryptoxanthin (papaya, tangerine, orange and watermelon) had twofold the plasma beta-cryptoxanthin concentrations of those with intakes of <4/wk (P for trend = 0.0009). In sum, the diet-plasma carotenoid and tocopherol correlations were generally low in Costa Rican adolescents. Intakes of beta-cryptoxanthin and papaya, a tropical fruit frequently consumed in Latin America, were the best predictors of beta-cryptoxanthin concentrations in plasma.

Anti-cancer function of phytic acid

Inositol hexaphosphate (InsP6 a.k.a. phytic acid or IP6) is ubiquitous. In the plant kingdom it is particularly abundant in cereals and legumes; in much smaller amounts IP6 and its lower phosphorylated forms (IP1−5) are contained in most mammalian cells, where they are important in regulating vital cellular functions. Both in vivo and in vitro experiments have demonstrated striking anticancer (preventive as well as therapeutic) effects of IP6. Inositol also is anti-carcinogenic, albeit to a lesser extent; it acts synergistically IP6 in inhibiting cancer. In addition to reduction in cell proliferation, IP6 increases differentiation of malignant cells often resulting in reversion to the normal phenotype. IP6 is quickly absorbed from the rat stomach and upper intestine and distributed as inositol and IP1. In vitro, it is instantaneously taken up by malignant cells undergoing variable dephosphorylation to inositol and IP1−5, pointing towards their role in mediating the action of IP6. In humans, IP6 has recently been detected in urine, plasma and other biological fluids; the levels fluctuating with ingestion or deprivation of IP6 or IP6-rich diet. As IP6 is high in high-fibre diets, these also may explain, at least in part, the epidemiological observation showing the association of ingesting high-fibre diets with a lower incidence of certain cancers. Along with safety, the reproducible efficacy of IP6 and inositol in the prevention of cancer in laboratory animals warrant their inclusion in our strategies for cancer prevention and perhaps therapy in humans. Aside from the anticancer action, IP6 and inositol also have numerous other health benefits. All these facts of normal physiological presence of IP6 in our body the level of which fluctuates with intake, association of an IP6-rich diet with low incidence of several diseases and vice versa, and finally reversal of some of these conditions, at least in part, by IP6 supplementation strongly argue in favour of its inclusion as an essential nutrient or perhaps a vitamin.

The high-fat Greek diet: a recipe for all?

OBJECTIVE

To examine critically the published results of dietary surveys on the fat content of the Greek diet, and to assess its evolution and its relationship to the health of the Greeks. To consider the implications of these findings for current views on the nature and health implications of the traditional Mediterranean diet and how best to define it for use in modern policy making.

DESIGN

A systematic review of the literature on food consumption in Greece.

SETTING

Greece.

RESULTS

The first fully published data on the fat content of the Greek diet-the Seven Countries Survey-relates only to a small number of adult males in Crete and Corfu; the legitimacy of extrapolating these results to the rest of Greece is questioned. Earlier studies and chemical validation of intakes point to a lower fat content of the traditional diet than that inferred for Crete. Nearly all later surveys relate only to urban groups in Athens (mostly case-control hospital-based samples) and a variety of non-representative Cretan groups. Only two studies are larger and more representative, but one uses FAO food balance-sheets to reflect the national diet, and the other surveyed school-age children in three out of the 52 Greek counties. Unfortunately recent dietary studies have proved unreliable, given the continuing lack of national food composition tables with survey methods which proved inaccurate for dietary fat content. A progressive upward trend in total and saturated fat intake appears to have occurred with all health indicators in relation to fat indicating remarkable increases in adult and childhood obesity with attendant progressive deterioration in cardiovascular mortality and its risk factors, ie hypertension and diabetes. These data emphasise the need to alter current nutritional advice in Greece, particularly when it focuses on the promotion of olive oil and a high-fat diet.

CONCLUSIONS

The findings reaffirm low-moderate fat policies for optimum health, within which olive oil can be an important component of the diet.

A prospective study of variety of healthy foods and mortality in women

BACKGROUND

To assess the overall influence of diet on health and disease in epidemiological studies, the habitual diet of the study participants has to be captured as a pattern rather than individual foods or nutrients. The simplest way to describe dietary preferences is to separate foods considered beneficial to health from foods considered to promote disease, and separate individuals on the basis of their regular consumption of these foods.

METHODS

We used data from 59 038 women participating in the prospective Mammography Screening Cohort in Sweden to investigate the influence of variety of healthy and less healthy foods on all-cause and cause-specific mortality.

RESULTS

Women who followed a healthy diet defined as consumption of a high variety of fruits, vegetables, whole grain breads, cereals, fish, and low fat dairy products had a significantly lower mortality than women who consumed few of these foods (3710 deaths total). Women who reported regularly consuming 16-17 healthy foods had a 42% lower all-cause mortality (95% CI: 32-50%) compared to women reporting consumption of 0-8 healthy foods with any regularity (P for trend <0.0001). For each additional healthy food consumed the risk of death was about 5% lower (95% CI: 4-6%). Cardiovascular mortality was particularly low among women who reported consuming a high variety of healthy foods. A less healthy diet defined as consumption of a high variety of red meats, refined carbohydrates and sugars, and foods high in saturated or trans fats was not directly associated with a higher overall mortality. However, women who reported consuming many less healthy foods were significantly more likely to die from cancer than those who consumed few less healthy foods.

CONCLUSIONS

A healthy diet can affect longevity. It appears more important to increase the number of healthy foods regularly consumed than to reduce the number of less healthy foods regularly consumed.

Disparate in vitro and in vivo antileukemic effects of resveratrol, a natural polyphenolic compound found in grapes

Resveratrol (trans-3,4',5-trihydroxystilbene), a polyphenol found in grapes and grape wine, has been reported to exhibit cardioprotective and chemopreventive activity against chemical carcinogenesis. It has also been shown to have growth inhibitory activity toward solid tumors in vivo. However, the antitumor activity of resveratrol against hematologic tumors in vivo has not been examined. In this study, the antileukemic activity of resveratrol in vitro and in vivo was examined using a mouse myeloid leukemia cell line (32Dp210). Treatment of 32Dp210 leukemia cells with resveratrol at micromolar concentrations (25-50 micromol/L) significantly and irreversibly inhibited their clonal growth in vitro. The clonal growth inhibition by resveratrol was associated with extensive cell death and an increase in hypodiploid (sub-G1) cells. Resveratol caused internucleosomal DNA fragmentation, suggesting apoptosis as the mode of cell death in 32Dp210 cells. DNA fragmentation was associated with activation of caspase-3, because cleavage of procaspase-3 was detected in resveratrol-treated cells. Although 32Dp210 cells treated with resveratrol in vitro did not produce leukemia in vivo, only a weak antileukemic effect of resveratrol was observed when administered orally. At doses of 8 mg or 40 mg/kg body daily, five times/wk, resveratrol did not affect the survival of mice injected with leukemia cells. Weak potential antileukemic activity of resveratrol was suggested only at a dose of 80 mg/kg body (2 survivors of 14 mice treated). Thus, despite strong antiproliferative and proapoptotic activities of resveratrol against 32Dp210 cells in vitro, a potential antileukemia effect in vivo, if present, occurs only in a small fraction of mice.

Influence of impaired mastication on nutrition

It has been suggested that people who suffer from impaired masticatory function may adapt food consistency to their oral status (which may lead to deficient nutrient intake) or rely on the digestive system to compensate for the lack of oral preparation of food (which may increase the likelihood of digestive diseases and decrease gut absorption). Masticatory deficiency thus may be detrimental to health. This article reviews evidence of the effects of masticatory deficiency on nutrition. The selection of relevant literature was based on Medline queries using the following key words: mastication, nutrition, digestion, diet, and disease risk. Earlier work not listed in Medline but related to the subject also was reviewed. Only publications available in English were selected for inclusion. It is difficult to draw conclusions from many of the reviewed studies due to issues related to study design, confounding variables, and the subjective nature of the measurements. In particular, data supporting a link between masticatory function and deficient dietary intake often are based on relatively weak correlations and cannot confer a causal relationship.

Assessment of pro-oxidant activity of foods by kinetic analysis of crocin bleaching

The pro-oxidant activity of potent oxidants and foods was determined using the kinetic analysis of crocin bleaching. In its reduced form, crocin has an absorption band at 443 nm, which disappears upon oxidation by a generic radical species. Hydroxyl radicals generated by hydrogen peroxide, peroxyl radicals from ABAP, and the stable free radical DPPH(*) were allowed to react with crocin in an aqueous solution at 40 degrees C. Pro-oxidant activity was taken as the ratio between the decrease in crocin absorbance at 5 min and the relevant oxidant concentration. The test proposed was used to evaluate the pro-oxidant activity of widely consumed foods such as pasteurized skim milk and bread. They both exerted significant pro-oxidant activities, which were attributed to the early nonenzymatic browning products formed upon heat treatment.

A cost-analysis of adopting a healthful diet in a family-based obesity treatment program

OBJECTIVE

To assess dietary costs during a family-based pediatric obesity intervention.

DESIGN

Families were randomized to one of two groups. Dietary and cost data were collected from a parent or child using three 24-hour recalls: at baseline, 6 months, and 12 months.

SUBJECTS

Thirty-one families with an obese 8- to 12-year-old child entered treatment, with complete dietary data provided from 20 families.

INTERVENTION

The 20-week behavior modification intervention emphasized increasing diet nutrient-density. Families attended group and individual sessions or group sessions.

MAIN OUTCOME MEASURES

Energy intake; percent of energy from protein, fat, and carbohydrate; servings and percent servings from food groups classified by nutrient density; and daily food costs.

STATISTICAL ANALYSES PERFORMED

Mixed analyses of variance, with group as the between-subject factor, and time as the within-subject factor.

RESULTS

No significant effect of group was found in any analyses. Significant decreases in percent overweight were observed at 6 and 12 months for children (-10.0+/-8.7 and -8.0+/-10.3, respectively) (mean+/-standard deviation) and parents (-6.7+/-10.3 and -5.3+/-14.1). Energy intake for parents and children combined significantly decreased from baseline (1,881+/-462) to 6 months (1,412+/-284), and 1 year (1,338+/-444). Servings from low-nutrient-dense foods significantly decreased from baseline (34.7+/-16.2) to 6 months (16.0+/-8.6) and 1 year (18.6+/-9.2), causing a significant increase in diet nutrient density. Dietary cost did not change at 6 months, but significantly decreased from baseline to 1 year ($6.77+/-2.41 to $5.04+/-1.80). Cost per 1,000 kcal did not significantly change.

APPLICATIONS/CONCLUSIONS

Adopting a lower-energy, nutrient-dense diet did not increase dietary costs over time. Consequently, cost should not be a barrier in the adoption of a healthful diet.

Dietary pattern analysis: a new direction in nutritional epidemiology

Recently, dietary pattern analysis has emerged as an alternative and complementary approach to examining the relationship between diet and the risk of chronic diseases. Instead of looking at individual nutrients or foods, pattern analysis examines the effects of overall diet. Conceptually, dietary patterns represent a broader picture of food and nutrient consumption, and may thus be more predictive of disease risk than individual foods or nutrients. Several studies have suggested that dietary patterns derived from factor or cluster analysis predict disease risk or mortality. In addition, there is growing interest in using dietary quality indices to evaluate whether adherence to a certain dietary pattern (e.g. Mediterranean pattern) or current dietary guidelines lowers the risk of disease. In this review, we describe the rationale for studying dietary patterns, and discuss quantitative methods for analysing dietary patterns and their reproducibility and validity, and the available evidence regarding the relationship between major dietary patterns and the risk of cardiovascular disease.

Dental status and satisfaction with oral function in a sample of community-dwelling elderly people in Japan

The purpose of this study was to determine the influence of dental status on oral function and satisfaction among a group of independently living elderly persons in an urban area of Japan. The study sample consisted of participants of the Senior Citizens' College from 1995 to 1999. Their dental status and oral satisfaction were measured by a questionnaire. The number of usable questionnaires was 3967, or 80.8% of the total sample. The mean age of the subjects was 66.5+/-4.3 years, and 52.2% were male. Twenty-nine percent of them had a natural dentition, and 7.0% were edentulous in both jaws. The prevalence of edentulism in the study sample was significantly lower (p < 0.01) than that for the national survey. Overall, 66.4% of the subjects were satisfied with their ability to chew, 56.2% with the appearance of their teeth, 63.1% with their ability to speak clearly, and 76.5% with their ability to taste food. For complete-denture wearers, the greatest dissatisfaction was with speech (28.5%); however, for the RPD wearers, it was with chewing ability (21.7%). Sixty-one percent of complete-denture wearers reported that they were satisfied with their chewing ability, but only 11% of them could eat all three of the evaluated foods without difficulty. The multiple stepwise logistic regression analyses showed that both dental status and self-assessed general health had a significant association with dissatisfaction with all four oral functions and self-assessed impairment of chewing ability. There were significant associations between the elderly subjects' dental status and oral function.

The influence of fish, meat and polyunsaturated fat intakes on platelet phospholipid polyunsaturated fatty acids in male Melbourne Chinese and Caucasian

OBJECTIVE

The aims of this study were to investigate (1) platelet phospholipid (PL) polyunsaturated fatty acid (PUFA) composition in subjects who were the Melbourne Chinese migrants, compared with those who were the Melbourne Caucasians and (2) the relationship between platelet PL PUFA and intake of fish, meat and PUFA.

DESIGN

Cross-sectional comparison of the Melbourne Chinese and Caucasians.

SETTING

Free-living male subjects.

SUBJECTS

Ninety-seven Melbourne Chinese migrants and 78 Melbourne Caucasians who were recruited in Melbourne.

OUTCOME MEASURES

Dietary intake was assessed using a semi-quantitative food frequency questionnaire. The platelet PUFA was measured by gas-liquid chromatography.

RESULTS

The Melbourne Chinese had significantly higher proportions of platelet PL 20:5n-3 (P=0.006), 22:6n-3 (P<0.0001), total n-3 (P=0.027) and 22:5n-6 (P=0.0002), and a significantly higher intake of fish (P=0.012) and white meat (P=0.0045) compared with the Melbourne Caucasians. In addition, the Melbourne Chinese had significantly lower proportions of 20:3n-6 (P=0.023), 20:4n-6 (P<0.002), 22:4n-6 (P<0.0001), total n-6 (P=0.037), 22:5n-3 (P<0.0001) and ratio of n-6/n-3 (P=0.011), and a significantly lower intake of red and total meat (P<0.0001) than the Melbourne Caucasians. Fish consumption was significantly positively correlated with platelet PL 20:5n-3 and 22:6n-3, and significantly negatively correlated with 22:5n-3 (P<0.05). Meat consumption was significantly positively correlated with 22:5n-3 and significantly negatively correlated with 22:5n-6, 20:5n-3 and 22:6n-3 (P<0.05). Dietary PUFA intake was significantly positively correlated with 20:3n-6, 22:4n-6 and 22:5n-3, and significantly negatively correlated with 22:5n-6, 20:5n-3 and 22:6n-3 (P<0.05).

CONCLUSIONS

Compared with Caucasians, the Melbourne Chinese had a significantly higher level of platelet PL n-3 PUFA, which might contribute to the low CVD mortality in this population. Platelet PL 20:5n-3 and 22:6n-3 were significantly positively correlated with fish intake, and negatively significantly correlated with dietary intake of meat and PUFA, while 22:5n-3 was significantly positively correlated with dietary meat and PUFA intake, and significantly negatively correlated with fish intake. Dietary intake of PUFA and fish are potential confounding factors for assessing the effects of meat consumption on platelet PL individual PUFA. Dietary intake of PUFA and meat did not influence the incorporation of fish long chain n-3 PUFA to platelet PL in this study population.

SPONSORSHIP

Palm Oil Research Institute of Malaysia, Meat Research Corporation Australia.

Fetal programming of cardiovascular function through exposure to maternal undernutrition

A substantial and robust body of epidemiological evidence indicates that prenatal dietary experience may be a factor determining cardiovascular disease risk. Retrospective cohort studies indicate that low birth weight and disproportion at birth are powerful predictors of later disease risk. This prenatal influence on non-communicable disease in later life has been termed programming. Maternal nutritional status has been proposed to be the major programming influence on the developing fetus. The evidence from epidemiological studies of nutrition, fetal development and birth outcome is, however, often weak and inconclusive. The validity of the nutritional programming concept is highly dependent on experimental studies in animals. The feeding of low-protein diets in rat pregnancy results in perturbations in fetal growth and dimensions at birth. The offspring of rats fed low-protein diets exhibit a number of metabolic and physiological disturbances, and are consistently found to have high blood pressure from early postnatal life. This experimental model has been used to explore potential mechanisms of programming through which maternal diet may programme the cardiovascular function of the fetus. Indications from this work are that fetal exposure to maternally-derived glucocorticoids plays a key role in the programming mechanism. Secondary to this activity, the fetal hypothalamic-pituitary-adrenal axis may stimulate renin-angiotensin system activity, resulting in increased vascular resistance and hypertension.

Consumer misperceptions of diet quality

OBJECTIVE

This study compares consumers' self-perceived diet quality with calculated diet quality to assess the degree of consumer misperception regarding one's own diet quality and to identify factors associated with such misperception.

DESIGN

The perceived diet quality was measured by consumers' self-perception of the overall healthfulness of their diet. The calculated diet quality was measured by the Healthy Eating Index, a 10-component indicator of overall diet quality developed from 3 consecutive days of 1-day 24-hour dietary recall and 2-day diet record.

SUBJECTS/SETTINGS

Measures of perceived and calculated diet quality were obtained for a sample of 2862 household meal planners/preparers from the 1989-90 Continuing Survey of Food Intake by Individuals and the Diet and Health Knowledge Survey.

OUTCOME

Dietary misperception was assessed by classifying respondents based on categories of perceived and calculated diet quality into three groups: optimists, realists, and pessimists.

STATISTICAL ANALYSES

Bivariate statistical tests and multivariate logistic regression were used for comparing the characteristics of optimists with the other two groups.

RESULTS

An estimated 40% of the population of household meal planner/preparers were optimists who perceived the quality of their diets to be better than their calculated diet quality. In multivariate analysis, household size, gender, education, smoking status, perceived health status, importance of nutrition in grocery shopping, and belief about the need for dietary change were found to be significant predictors of being optimistic about diet quality. Nutritionists and health professionals need to be aware of this misperception and alert dietary optimists about their false perceptions of diet quality.

Mediterranean diets and cardiovascular disease

Coronary heart disease remains the leading cause of death in the Western world. Among these countries, however, there is a marked discrepancy in the prevalence of heart disease in spite of similar traditional risk factor profiles. This is undoubtedly due to differences in lifestyle, the most important of which are diet and exercise. Both epidemiologic data and clinical trials suggest that the beneficial impact of specific dietary and lifestyle changes on cardiac event rates could be greater than that achieved by any of the drug or revascularization trials to date.

Immunomodulatory activity of resveratrol: suppression of lymphocyte proliferation, development of cell-mediated cytotoxicity, and cytokine production

trans-Resveratrol, a phytoalexin found in grapes, wine, and other plant products, has been shown to have anti-inflammatory, antioxidant, and antitumor activities. Many of these beneficial effects of resveratrol require participation of the cells of the immune system; however, the effect of resveratrol on the development of immunological responses remains unknown. We have investigated the effect of resveratrol on mitogen/antigen-induced proliferation of splenic lymphocytes, induction of cytotoxic T lymphocytes (CTLs) and lymphokine activated killer (LAK) cells, and the production of the cytokines interferon (IFN)-gamma, interleukin (IL)-2, tumor necrosis factor (TNF)-alpha, and IL-12. We found that mitogen-, IL-2-, or alloantigen-induced proliferation of splenic lymphocytes and the development of antigen-specific CTLs were suppressed significantly at 25-50 microM resveratrol. The generation of LAK cells at similar concentrations was less sensitive to the suppressive effect of resveratrol. The suppression of cell proliferation and CTL generation by resveratrol was not only reversible, but in some cases the response (mitogen/IL-2-induced proliferation and CTL generation) was actually enhanced following pretreatment of cells with resveratrol. Resveratrol also inhibited the production of IFN-gamma and IL-2 by splenic lymphocytes, and the production of TNF-alpha and IL-12 by peritoneal macrophages. The inhibition of cytokine production by resveratrol was irreversible. Further, resveratrol blocked the activation of the transcription factor NF-kappaB without affecting basal NF-kappaB activity. The latter result suggests that resveratrol inhibits cell proliferation, cell-mediated cytotoxicity, and cytokine production, at least in part through the inhibition of NF-kappaB activation.

Beef tallow, but not perilla or corn oil, promotion of rat prostate and intestinal carcinogenesis by 3,2'-dimethyl-4-aminobiphenyl

The modifying effects of three kinds of fat (corn oil, beef tallow or perilla oil, each at 20% in the diet) on F344 rat prostate carcinogenesis induced by 3,2'-dimethyl-4-aminobiphenyl (DMAB) were investigated. Non-invasive carcinomas of the ventral prostate were induced by DMAB alone and invasive carcinomas of the other prostate lobes and seminal vesicles by DMAB and testosterone propionate (TP). Eight groups of F344 rats were initiated with 50 mg / kg body weight of DMAB at 2-week intervals for the first 20 weeks, four also receiving TP, extended until week 60. The animals received basal chow powder diet or one of three high fat diets throughout the experiment (60 weeks). One further group served as a non-carcinogen-treated control maintained on basal chow powder diet. Beef tallow significantly increased the development of ventral prostate carcinomas with DMAB alone (from 15 to 45%, P < 0.05), while perilla oil reduced the incidence of prostatic intraepithelial neoplasia (PIN) in the ventral lobe of rats given DMA + TP (from 70 to 10%, P < 0.01), but not in those given DMAB alone. No other effects of high fats were observed regarding PIN or invasive cancers of the dorsolateral and anterior prostate or seminal vesicles. A satellite experiment demonstrated that all high fat diets for 4 weeks increased the 5-bromo-2-deoxyuridine (BrdU) labeling index of prostate epithelial cells, suggesting that a high fat intake, irrespective of the fatty acid composition, may accelerate cell kinetics in the prostate. Of the three high fat diets, beef tallow was also found to increase intestinal carcinogenesis. Thus, the present data revealed carcinogenesis in the prostate and intestine to be promoted by beef tallow.

Dual action of eicosapentaenoic acid in hepatoma cells: up-regulation of metabolic action of insulin and inhibition of cell proliferation

Exogenous administration of eicosapentaenoic acid (EPA) improves insulin sensitivity, but its precise mechanism remains unknown. Here we show that EPA stimulates the intracellular insulin signaling pathway in hepatoma cells. Exposure of these cells to EPA caused up-regulation of several insulin-induced activities including tyrosine phosphorylation of insulin receptor substrate-1, insulin receptor substrate-1-associated phosphatidylinositol 3-kinase, and its downstream target Akt kinase activity as well as down-regulation of gluconeogenesis. In contrast, EPA decreased mitogen-activated protein kinase activity and inhibited cell proliferation. These findings raise the possibility that EPA up-regulates metabolic action of insulin and inhibits cell growth in humans.

Suplementação de vitaminas na prevenção de câncer

Este trabalho constitui uma revisão de dados epidemiológicos sobre a relação entre o consumo de vitaminas e prevenção de câncer. Estudos observacionais evidenciam uma associação inversa consistente entre a ingestão de frutas e hortaliças e risco de câncer, e um efeito protetor das vitaminas C, E e dos carotenóides contra certos tipos de câncer. Resultados de estudos de intervenção, na prevenção primária de câncer, são contraditórios, sendo que em dois desses estudos o beta-caroteno, suplementado em doses consideradas farmacológicas, isolado ou associado à vitamina E ou à vitamina A, mostrou-se deletério para tabagistas. Ao contrário, a ingestão de doses mais fisiológicas de antioxidantes parece ser mais eficaz, sendo que a ação sinérgica dessas substâncias na quimioprevenção de câncer já foi demonstrada tanto em modelo in vivo de carcinogênese quanto em estudo epidemiológico de intervenção. Como estratégia de prevenção de câncer preconiza-se o consumo de dietas ricas em frutas e hortaliças, que aportem cerca de 150 mg de vitamina C, 30 mg de vitamina E e 4 mg de carotenóides. A ingestão de quantidades mais elevadas, na forma de suplementos, não está recomendada.

Randomized trial of a "talking computer" to improve adults' eating habits

PURPOSE

To assess efficacy of an intervention delivered by an interactive, computer-controlled telephone system to improve individuals' diets.

DESIGN

Randomized controlled trial.

SETTING

Large multispecialty group practice.

SUBJECTS

Two hundred ninety-eight adults who were both sedentary and had suboptimal diet quality.

INTERVENTION

Weekly communication for 6 months via a totally automated, computer-based voice system. Among intervention group subjects, the system monitored dietary habits and provided educational feedback, advice, and behavioral counseling. Control group subjects received physical activity promotion counseling.

MEASURES

Daily intake of fruits, vegetables, red and processed meats, whole fat dairy foods, and whole grain foods estimated from a food frequency questionnaire.

RESULTS

Mean age 45.9 years, 72% women, 45% white, and 45% African-American. Among participants who completed diet assessments, compared with the control group, the intervention raised fruit intake a mean of 1.1 servings per day (95% confidence interval [CI] .4, 1.7). On a 0 to 100 global diet quality score combining all five food groups, intervention participants improved their mean score 9 (95% CI 4, 13) points more than in the control group. The intervention also raised dietary fiber intake 4.0 g/d (95% CI .1, 7.8) and decreased saturated fat, as a proportion of energy intake, by 1.7% (95% CI -2.7, -.7).

CONCLUSIONS

This computer-based telecommunications dietary behavior intervention helped improve participants' overall diet.

Testosterone and oestradiol in relation to tobacco smoking, body mass index, energy consumption and nutrient intake among adult men

There is substantial evidence linking steroid hormones and diet to cancer aetiology. The evidence on lifestyle determinants of steroid hormones, however, is limited. We have conducted a study to identify dietary and other lifestyle predictors of testosterone and oestradiol among adult men. Subjects were 112 healthy Greek men, recruited as controls in a case-control study on the aetiology of liver cancer. Demographic data and detailed histories of smoking habits and alcohol consumption were recorded. Diet was assessed through an interviewer-administered validated food-frequency questionnaire. Serologic measurements of oestradiol, testosterone and sex hormone binding globulin were also conducted. We developed linear regression models to evaluate the associations of smoking and dietary factors with serum testosterone and oestradiol. The results indicate that, among men, both testosterone and oestradiol serum levels decline with age, whereas body mass index may be inversely related with testosterone and positively with oestradiol. The evidence concerning alcohol in relation to these hormones is inconclusive. Emerging evidence concerning smoking suggests positive associations with both hormones in the blood. The principal nutritional findings are a positive association of carbohydrate intake with testosterone levels and a set of inverse associations of vitamins with oestradiol.

The association of fatty acids with prostate cancer risk

BACKGROUND

Animal studies indicate that omega-6 fatty acids promote and omega-3 fatty acids inhibit tumor development. This pilot study was designed to evaluate whether these fatty acids are associated with human prostate cancer.

METHODS

Levels of erythrocyte membrane omega-3 and omega-6 fatty acids were determined for 67 incident prostate cancer cases and 156 population-based controls.

RESULTS

Prostate cancer risk was increased in the highest compared to the lowest quartile of alpha-linolenic acid (OR = 2.6, 95% CI = 1.1-5.8, trend P = 0.01). Positive associations were also observed with higher levels of linoleic acid (OR = 2.1, 95% CI = 0.9-4.8) and total omega-6 fatty acids (OR = 2.3, 95% CI = 1.0-5.4).

CONCLUSIONS

Results are consistent with other studies showing that linoleic and total omega-6 fatty acids increase risk of prostate cancer. Contrary to animal studies, alpha-linolenic acid was also positively associated with risk. Further research will be required to clarify the role of these fatty acids in human prostate cancer.

Aqueous extract isolated from Platycodon grandiflorum elicits the release of nitric oxide and tumor necrosis factor-alpha from murine macrophages

Herbal medicines are increasingly being utilized to treat a wide variety of disease processes. Aqueous extract from the root of Platycodon grandiflorum A. DC (Campanulaceae), Changkil (CK), is reported to have antitumor and immunomodulatory activities; however, the mechanism underlying its therapeutic effect is not known. In the present study we examined the effects of CK on the release of nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha), and on the gene expression of iNOS and TNF-alpha in mouse macrophages. CK elicited a dose-dependent increase in NO and TNF-alpha production in cultured macrophages. CK significantly affected secretion at concentrations of more than 5 micrograms/ml, and its maximum effect was at concentration of 100 micrograms/ml. Reverse transcription polymerase chain reaction showed that increases in NO and TNF-alpha secretion were due to an increase in inducible NO synthase mRNA and TNF-alpha mRNA, respectively. Transient expression assays with NF-kappa B binding sites linked to the luciferase gene revealed that CK-induced increase of inducible NO synthase mRNA and TNF-alpha mRNA were mediated by the NF-kappa B transcription factor complex. These results demonstrate that CK stimulates NO and TNF-alpha release and is able to upregulate iNOS and TNF-alpha expression through NF-kappa B transactivation and this may be a mechanism whereby this herbal medicine elicits its therapeutic effects.