The fruit of Acanthopanax senticosus Harms improves arterial stiffness and blood pressure: a randomized, placebo-controlled trial

BACKGROUND/OBJECTIVES@#Arterial stiffness and endothelial dysfunction are 2 of the independent predictors for cardiovascular disease, while Acanthopanax senticosus Harms (ASH) is a traditional medicinal plant that can improve cardiovascular health. This study aimed to investigate the efficacy of the fruit of ASH on vascular function in apparently healthy subjects. @*SUBJECTS/METHODS@#A 12-week, randomized, double-blind, placebo-controlled design, consisting of healthy adults with at least 2 of the following 3 conditions: borderline high blood pressure (BP; 120 mmHg ≤ systolic BP ≤ 160 mmHg or 80 mmHg ≤ diastolic BP ≤ 100 mmHg), smoking (≥10 cigarettes/day), and borderline blood lipid levels (220 ≤ total cholesterol ≤ 240, 130 ≤ low density lipoprotein cholesterol ≤ 165, or 150 ≤ triglyceride ≤ 220 mg/dL). Randomly assigned 76 subjects who received a placebo or 2 doses of ASH fruit (low, 500 mg/day; high, 1,000 mg/day) completed the intervention. Brachial-ankle pulse wave velocity (baPWV), flow-mediated dilation, carotid intima-media thickness, and BP were measured both at baseline and following the 12-week intervention. Endothelial nitric oxide synthase (eNOS) phosphorylation was assessed by western blotting. @*RESULTS@#Compared with the placebo group, the low-dose group showed more significant changes after the 12-week intervention period in terms of systolic BP (0.1 vs. −7.7 mmHg; P = 0.044), baPWV (31.3 vs. −98.7 cm/s; P = 0.007), and the ratio of phospho-eNOS/eNOS (0.8 vs. 1.22; P = 0.037). @*CONCLUSIONS@#These results suggest that ASH fruit extract at 500 mg/day has the potential to improve BP and arterial stiffness via endothelial eNOS activation in healthy adults with smoking and the tendency of having elevated BP or blood lipid parameters.

A big picture view of precision nutrition: from reductionism to holism / 한국영양학회지

PURPOSE: This review describes the historical changes in nutrition philosophy from a reductionist to a holistic approach during the 20th century. Also, the role and efficient use of a holistic approach to precision nutrition are discussed. RESULTS: Over the past century, significant progress has been made in human nutrition research, unraveling fundamental mechanisms of single nutrients on single targets or pathways. This kind of a reductionist approach has helped to save populations from nutrient deficiency diseases and improve associated health outcomes in large parts of the world. However, a new set of nutrition problems, like obesity and diet-related chronic diseases, are growing each year worldwide, increasing the financial burden on the health care system. A linear cause-effect association between single nutrients and a single physiologic effect, is insufficient to solve the complex nutrition-health relationships. Research that involves a more holistic rather than reductionist approach is needed to tackle a new set of nutrition problems. Recent advances in technology, informatics, and statistical methods are enabling an understanding of the diversity of individuals and the complex interactions between foods and human bodies, leading to the concept of “precision nutrition.” CONCLUSION: The emerging goal of precision nutrition is to provide tailored dietary advice for maintaining health and preventing obesity and diet-related chronic diseases. The parts are already being installed. To grab the complexity, reductionism and holism must be used interdependently.

Association of coffee consumption with health-related quality of life and metabolic syndrome in Korean adults: based on 2013 ~ 2016 Korea National Health and Nutrition Examination Survey / 한국영양학회지

PURPOSE: This study examined the association of the type and frequency of coffee consumption with the health-related quality of life and metabolic bio-markers in adult men and women from the 2013 ~ 2016 Korea National Health and Nutrition Examination Survey (KNHANES). METHODS: A total of 11,201 subjects (4,483 men and 6,718 women) were classified according to the type of coffee consumption (non-coffee, black coffee, 3-in-1 coffee) and type and frequency of coffee consumption (non-coffee, ≤2 times/day of black coffee, > 2 times/day of black coffee, ≤2 times/day of 3-in-1 coffee, > 2 times/day of 3-in-1 coffee) using food frequency questionnaires. Dietary nutrient intake data were assessed using food frequency questionnaires. The health-related quality of life was measured using the EuroQol-5 dimension (EQ-5D) and EQ-5D index score. Data on metabolic bio-markers were obtained from a health examination. RESULTS: Among men and women, the proportion of subjects with an energy intake below the estimated energy requirement (EER) was lower among the 3-in-1 coffee consumption group, and the proportion of subjects with iron intakes below the estimated average requirements (EAR) was lower among the 3-in-1 coffee consumption group. Women (OR: 0.810, 95% CI: 0.657 ~ 0.998) with the ≤2 times/day of 3-in-1 coffee had a lower risk of impaired health-related quality of life (lowest 20% level in the EQ-5D score) compared to the non-coffee consumers after a multivariable adjustment. In both men and women, the type and frequency of coffee consumption was not associated with metabolic bio-markers risk after multivariable adjustment. CONCLUSION: These results suggest that 3-in-1 coffee consumption may be associated with a lower risk of impaired health-related quality of life and may not be associated with the metabolic bio-markers risk in adult men and women.

Heme Oxygenase-1 Induction and Anti-inflammatory Actions of Atractylodes macrocephala and Taraxacum herba Extracts Prevented Colitis and Was More Effective than Sulfasalazine in Preventing Relapse

BACKGROUND/AIMS: In inflammatory bowel disease (IBD), repeated bouts of remission and relapse occur in patients and can impose a risk of colitis-associated cancer. We hypothesized that plant extracts of Atractylodes macrocephala (AM) or Taraxacum herba (TH) may be better than sulfasalazine for treating this disease because these extracts can promote additional regeneration. METHODS: Murine intestinal epithelial IEC-6 cells were pretreated with AM or TH before a lipopolysaccharide (LPS)-induced challenge. Acute colitis was induced with 7 days of dextran sulfate sodium (DSS) in male C57BL/6 mice, and extracts of AM and TH were administered for 2 weeks before DSS administration. RESULTS: In vitro studies demonstrated that AM or TH treatment reduced LPS-induced COX-2 and tumor necrosis factor-α mRNA levels but increased heme oxygenase-1 (HO-1). Oral preadministration of AM and TH rescued mice from DSS-induced colitis by inhibiting inflammatory mediators via inactivated extracellular signal regulated kinase and repressed nuclear factor κB and signal transducer and activator of transcription 3, but the effect was weaker for sulfasalazine than that for the extracts. Anti-inflammatory activities occurred via the inhibition of macrophage and T lymphocyte infiltrations. Unlike sulfasalazine, which did not induce HO-1, TH extracts afforded significant HO-1 induction. CONCLUSIONS: Because the AM or TH extracts were far superior in preventing DSS-induced colitis than sulfasalazine, AM or TH extracts can be considered natural agents that can prevent IBD relapse.

Effects of the Combination Herbal Extract on Working Memory and White Matter Integrity in Healthy Individuals with Subjective Memory Complaints : A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

OBJECTIVES: The combination extract of four kinds of herbs, Gastrodia elata, Liriope platyphylla, Dimocarpus longan, and Salvia miltiorrhiza, has shown to have memory improving effects in mice. The aim of this study was to investigate the efficacy and safety of the herbal mixture for improving working memory as well as microstructural changes in white matter integrity in individuals with subjective memory complaints. METHODS: Seventy-five individuals with subjective memory complaints were assigned to receive either placebo (n = 15) or herbal mixture (low-dose group, n = 30 and high-dose group, n = 30) supplementation in an 8-week, randomized, double-blind, placebo-controlled clinical trial. Changes in working memory performance and fractional anisotropy (FA) values reflecting white matter integrity from baseline to 8-week endpoint were assessed. RESULTS: The herbal mixture group showed an increase in working memory performance compared to the placebo group (p for interaction = 0.001). In addition, the herbal mixture group showed an increase in FA values in the temporo-parietal regions (corrected p < 0.05), which are crucially involved in working memory function and are among the most affected regions in patients with cognitive impairments. CONCLUSIONS: Findings from this study indicate that the herbal mixture may be a promising therapeutic option for individuals with subjective memory complaints.

Evidence-based estimation of health care cost savings from the use of omega-3 supplementation among the elderly in Korea

BACKGROUND/OBJECTIVES: By the year 2050, thirty-eight percent of the Korean population will be over the age of 65. Health care costs for Koreans over age 65 reached 15.4 trillion Korean won in 2011, accounting for a third of the total health care costs for the population. Chronic degenerative diseases, including coronary heart disease (CHD), drive long-term health care costs at an alarming annual rate. In the elderly population, loss of independence is one of the main reasons for this increase in health care costs. Korean heath policies place a high priority on the prevention of CHD because it is a major cause of morbidity and mortality. SUBJECTS/METHODS: This evidence-based study aims to the estimate potential health care cost savings resulting from the daily intake of omega-3 fatty acid supplementation. Potential cost savings associated with a reduced risk of CHD and the medical costs potentially avoided through risk reduction, including hospitalizations and physician services, were estimated using a Congressional Budget Office cost accounting methodology. RESULTS: The estimate of the seven-year (2005-2011) net savings in medical costs resulting from a reduction in the incidence of CHD among the elderly population through the daily use of omega-3 fatty acids was approximately 210 billion Korean won. Approximately 92,997 hospitalizations due to CHD could be avoided over the seven years. CONCLUSIONS: Our findings suggest that omega-3 supplementation in older individuals may yield substantial cost-savings by reducing the risk of CHD. It should be noted that additional health and cost benefits need to be revisited and re-evaluated as more is known about possible data sources or as new data become available.

Effects of a Pueraria lobata-root based combination supplement containing Rehmannia glutinosa and aerobic exercise on improvement of metabolic dysfunctions in ovariectomized rats / 한국영양학회지

PURPOSE: There is a fair amount of evidence indicating that increased risk of obesity and insulin resistance is associated with postmenopausal state, but can be modulated by diet and exercise. In this study, we explored whether a Pueraria lobata root-based supplement containing Rehmannia glutinosa (PR) and/or aerobic treadmill exercise can modify the metabolic changes associated with estrogen deficiency. METHODS: Seventy rats were randomly assigned to the following groups for 8 weeks (n=10 per group): SHAM, sham-operated; PR0, ovariectomized (OVX) control; PR200, OVX with PR200 mg/kg B.W; PR400, OVX with PR400 mg/kg B.W; EPR0, OVX with exercise; EPR200, OVX with exercise and PR200 mg/kg B.W; EPR400, OVX with exercise and PR400 mg/kg B.W. RESULTS: OVX induced significant increases in body weight, food intake, fat mass, LDL-cholesterol, and fasting blood glucose, confirming induction of menopausal symptoms. PR supplementation or exercise significantly suppressed the above mentioned changes through different regulatory elements in adipose tissue: PR supplement upregulated adiponectin gene expression and aerobic exercise upregulated adiponectin and insulin receptor gene expression and a combination of PR supplement and aerobic exercise showed an additive effect on adiponectin gene expression. CONCLUSION: Taken together, the results of this study suggest that PR supplement has a potential to provide health benefits in OVX rats through leptin and adiponectin secretion. In addition, the data suggest that combination of exercise and PR would have additive effects on metabolic dysfunction associated with estrogen deficiency.

Protective effects of Acanthopanax koreanum Kakai extract against carbon tetrachloride-induced liver injury in Sprague-Dawley rats / 한국영양학회지

PURPOSE: This study was conducted in order to investigate the protective effects of ethanolic extract of Acanthopanax koreanum Nakai (AE) against carbon tetrachloride (CCl4)-induced liver injury in rats. METHODS: Male Sprague-Dawley rats were randomly divided into four groups in order to receive the following experimental diets with intraperitoneal injection of CCl4 (2.0 mL/kg body weight, 20% solution 0.65 mL) for eight weeks (n = 8 per group): CCl4 control (CON), CCl4 + AE 1% (AE1), CCl4 + AE 3% (AE3), or CCl4 + acanthoic acid 0.037%, which is equivalent to AE 3% (AA). RESULTS: Highest serum ALT activity and albumin level were observed in the CCL4 control group, but showed a significant decrease by either AE or AA supplementation in a dose-dependent manner (p = 0.0063 and 0.0076, respectively). Both hemotoxylin and eosin staining and Masson's staining indicated remarkable prevention of CCl4-induced liver damage in the AE3 group. TNFalpha and IL-6 production were significantly lowered in the AE treated groups, but not in the AA group (p = 0.0016 and p = 0.0002, respectively). The effects of AE3 were greater than those of AA for inflammation and liver toxicity biomarkers. CONCLUSION: Taken together, the results suggested that ethanolic extract of Acanthopanax koreanum Nakai provided hepa-toprotective effects, leading to the reduction of inflammatory response. In addition, the effect of AE was superior to that of single compound AA.

Systematic review of the effect of dried ginger powder on improvement of nausea and vomiting associated with early pregnancy or motion sickness / 한국영양학회지

PURPOSE: Ginger (Zingiber officinale) has been widely used as an antiemetic agent. This systematic review was aimed at evaluation of the effect of dried ginger powder supplementation on improvement of nausea and vomiting associated with early pregnancy or motion sickness. METHODS: We searched Pubmed, Cochrane, Science Direct, and KISS (Korean studies Information Service System) using keywords such as ginger or Zingiber officinale in combination with nausea, vomiting, motion sickness, or pregnancy, published in March 2013. RESULTS: The strength of the evidence was evaluated on the selected 12 RCTs (randomized controlled trials). Eleven trials including 2,630 subjects showed that supplementation with dried ginger powder resulted in significant improvement of nausea or vomiting related to early pregnancy or motion sickness. Among the nine studies including 809 women in early pregnancy before 20 weeks of gestation, ginger supplementation was superior to placebo in five studies (n = 305), and as effective as positive control (vitamin B6 or dimenhydrinate) in four studies (n = 504). Ginger intake significantly reduced the episodes or severity of vomiting related to motion sickness compared to placebo or showed the same effect as several antiemetic drugs in two studies (n = 1,821). CONCLUSION: Our findings added evidence indicating that ginger powder supplements might improve the symptoms of nausea or vomiting related to early pregnancy or motion sickness without significant adverse events.

Garlic powder intake and cardiovascular risk factors: a meta-analysis of randomized controlled clinical trials

BACKGROUND/OBJECTIVES: Although preclinical studies suggest that garlic has potential preventive effects on cardiovascular disease (CVD) risk factors, clinical trials and reports from systematic reviews or meta-analyses present inconsistent results. The contradiction might be attributed to variations in the manufacturing process that can markedly influence the composition of garlic products. To investigate this issue further, we performed a meta-analysis of the effects of garlic powder on CVD risk factors. MATERIALS/METHODS: We searched PubMed, Cochrane, Science Direct and EMBASE through May 2014. A random-effects meta-analysis was performed on 22 trials reporting total cholesterol (TC), 17 trials reporting LDL cholesterol (LDL-C), 18 trials reporting HDL cholesterol (HDL-C), 4 trials reporting fasting blood glucose (FBG), 9 trials reporting systolic blood pressure (SBP) and 10 trials reporting diastolic blood pressure (DBP). RESULTS: The overall garlic powder intake significantly reduced blood TC and LDL-C by -0.41 mmol/L (95% confidence interval [CI], -0.69, -0.12) (-15.83 mg/dL [95% CI, -26.64, -4.63]) and -0.21 mmol/L (95% CI, -0.40, -0.03) (-8.11 mg/dL [95% CI, -15.44, -1.16]), respectively. The mean difference in the reduction of FBG levels was -0.96 mmol/L (95% CI, -1.91, -0.01) (-17.30 mg/dL [95% CI, -34.41, -0.18]). Evidence for SBP and DBP reduction in the garlic supplementation group was also demonstrated by decreases of -4.34 mmHg (95% CI, -8.38, -0.29) and -2.36 mmHg (95% CI, -4.56, -0.15), respectively. CONCLUSIONS: This meta-analysis provides consistent evidence that garlic powder intake reduces the CVD risk factors of TC, LDL-C, FBG and BP.

Calcium Intakes in Korean and American Populations

Calcium intake has been insufficient in all age groups in previous Korean national surveys. This study was conducted to investigate calcium intake in Korean and American populations at different ages. We analyzed two national survey data: the 2007~2009 Korean National Health and Nutrition Examination Survey (KNHANES) and the 2007~2008 National Health and Nutrition Examination Survey (NHANES). Statistically, survey procedures were applied using the weight, cluster, and strata variables. The mean calcium intake of Koreans at ages of 1~2 y, 3~5 y, 6~11 y, 12~18 y, 19~64 y, and 65+y was lower than American populations at those ages. The sufficient proportions based on Korean Estimated Average Requirement (EAR) of 1~2 y, 3~5 y, 6~11 y, 12~18 y, 19~64 y, and 65+y in Koreans were 45.5%, 33.1%, 24.3%, 16.6%, 32.7%, and 19.0%. While the sufficient rates based on American EAR of 1~3 y, 4~8 y, 9~13 y, 14~18 y, 19~30 y, 31~50 y, 51~70 y, and 71+y in US population were 88.5%, 54.4%, 35.2%, 35.8%, 55.3%, 55.2%, 40.6%, and 24.5%. Overall, the major foods contributing to calcium intakes in Koreans were milk, baechukimchi, and anchovies, whereas, milk products, pasta, or bread were major contributions to calcium in American populations. The calcium supplement intakes in the American population were 5.5 mg (1~2 y), 15.5 mg (3~5 y), 13.9 mg (6~11 y), 35.7 mg (12~18 y), 150.3 mg (19~64 y) and 334.4 mg (> or =65 y). These results suggest that Korean adolescents and older adults are the most insufficient in dietary calcium intakes among Koreans. In order to accurately estimate calcium intakes in Korean populations, calcium supplements and calcium-fortified foods should be considered.

Oxidation of fatty acid may be enhanced by a combination of pomegranate fruit phytochemicals and acetic acid in HepG2 cells

We investigated whether the combination of phytochemicals and acetic acid in the form of fruit vinegar provides an additive effect on changes of mRNA levels related to fatty acid oxidation in human hepatocyte (HepG2). Among the seven fruit vinegars (Rubuscoreanus, Opuntia, blueberry, cherry, red ginseng, mulberry, and pomegranate) studied, treatment of HepG2 with pomegranate vinegar (PV) at concentrations containing 1 mM acetic acid showed the highest in vitro potentiating effect on the mRNA expression levels of peroxisome proliferator-activated receptor alpha, carnitinepalmitoyl transferase-1, and acyl-CoA oxidase compared to the control group (P < 0.05). Reversed-phase liquid chromatography in combination with quadrupole time-of-flight mass spectrometry analysis revealed four potential compounds (punicalagin B, ellagic acid, and two unidentified compounds) responsible for altered gene expression in HepG2 cells treated with PV as compared with the others. Further investigations are warranted to determine if drinking PV beverages may help to maintain a healthy body weight in overweight subjects.

Dietary flavan-3-ols intake and metabolic syndrome risk in Korean adults

Flavan-3-ols are a subclass of flavonoids found in a variety of foods including teas. The effects of flavan-3-ols on the risk of metabolic syndrome (MetS) have been investigated, generally focusing on tea catechins or individual flavan-3-ol rich foods, but there is little information on dietary flavan-3-ols intake and risk of MetS in population-based studies. In this cross-sectional study, we examined the association between dietary flavan-3-ols intake and the risk of MetS in Korean adults. Subjects comprised 1,827 men and 2,918 women aged 20-69 years whose data was included in the 2008 Korean National Health and Nutrition Examination Survey. This survey was conducted between January 2008 and December 2008. Total flavan-3-ols intakes were calculated from 24-hour dietary recalls using a flavonoids database. Thirty percent of the male subjects and 24% of the female subjects were reported as having MetS. In the female subjects, flavan3-ols intake was inversely associated with the risk of MetS after adjusting for potential confounders (5th vs. 1st quintile, OR = 0.64, 95% CI = 0.45-0.91, P for trend = 0.384). The main food source of flavan-3-ols was green tea followed by apples and grapes. Among MetS components, flavan3-ols intake was inversely associated with the risk of high blood pressure after adjusting for potential confounders (5th vs. 1st quintile, OR = 0.64, 95% CI = 0.45-0.90, P for trend = 0.005). No significant association between flavan-3-ols intake and risk of MetS was found in the male subjects. After stratified analysis by obesity (BMI > or = 25 or BMI < 25), however, flavan3-ols intake was inversely related to the risk of hypertension in non-obese men. These results suggest that dietary flavan-3-ols intake may have beneficial effects on MetS risk by reducing the risk of hypertension. The effects of flavan-3-ols intake dependent on obesity need further investigation.

Comparisons of dietary behavior, food intake, and satisfaction with food-related life between the elderly living in urban and rural areas

The present study was performed to evaluate dietary behavior, food intake, and satisfaction with food-related life regarding the elderly residing in different regions of Korea. The survey was conducted on 631 individuals over 55 years old in either urban or rural areas. The survey was carried out using a questionnaire including dietary behavior, mini dietary assessment, and a food frequency questionnaire. The average age of the rural elderly was higher than that of the urban elderly whereas, education level and economic status were higher in the urban elderly compared to the rural elderly. The intake of dairy products, meats, instant foods, snacks, and the use of nutrient supplementation were significantly higher in the urban elderly than those of the rural elderly (p = 0.000). The intake of vegetables was significantly higher in the rural elderly (p = 0000). Furthermore, the rural elderly were more satisfied with food-related life and had better balanced diets than those of the urban elderly. Taken together, the results of this study revealed that customized nutritional management and education for adequate meals in different regions should be developed and provided in order to improve the quality of healthy living for the elderly.

Application of Dietary Reference Intakes for Codex Nutrient Reference Values

Codex Nutrient Reference Values (NRVs) were based on the 1988 Helsinki report and a single set of NRVs was established for the general population over 3 years for the purpose of food labeling in 1993. Dietary Reference Intakes (DRIs) with new concepts were developed in many countries recently. Hence there has been broad discussion regarding establishment of new NRVs using DRIs, which include estimated average requirement (EAR), recommended intake (RI or RDA), adequate intake (AI), and tolerable upper intake level (UL) in the world. This study was carried out to review various possible values for Codex NRVs such as population-weighted EAR, population-weighted RDA, and population-based RDA. The values were simulated using DRIs and population distribution of Korea, USA, Japan, Philippines, Germany and England, and compared to the current Codex values and the highest RDA and the lowest UL among populations with different life-stage. Since population weighted/based values are necessary to be updated according to the population changes and are different across countries, inconsistency can be a serious barrier in international transactions. For some of nutrients such as vitamin A and zinc, values based on population-based RDA or the highest RDA were higher than the lowest UL. Therefore, careful considerations should be given before establishing Codex NRVs.

Postprandial hypoglycemic effect of mulberry leaf in Goto-Kakizaki rats and counterpart control Wistar rats

Postprandial hypoglycemic effect of mulberry leaf (Morus alba L.) was compared in two animal models: Goto-Kakizaki (GK) rats, a spontaneous non-obese animal model for type II diabetes, and their counterpart control Wistar rats. First, the effect of a single oral administration of mulberry leaf aqueous extract (MLE) on postprandial glucose responses was determined using maltose or glucose as substrate. With maltose-loading, MLE reduced peak responses of blood glucose significantly in both GK and Wistar rats (P < 0.05), supporting the inhibition of alpha-glucosidase by MLE in the small intestine. With glucose-loading, MLE also significantly reduced blood glucose concentrations, measured at 30 min, in both animal models (P < 0.01), proposing the inhibition of glucose transport by MLE. Next, dried mulberry leaf powder (MLP) was administered for 8 weeks by inclusion in the diet. By MLP administration, fasting blood glucose was significantly reduced at weeks 4 and 5 (P < 0.05), but then returned to values that were similar to those of the control at the end of experimental period in GK rats. Insulin, HOMA-IR, C-reactive protein, and triglycerides tended to be decreased by MLP treatment in GK rats. All other biochemical parameters were not changed by MLP administration in GK rats. Collectively, these findings support that MLE has significant postprandial hypoglycemic effect in both non-obese diabetic and healthy animals, which may be beneficial as food supplement to manage postprandial blood glucose. Inhibitions of glucose transport as well as alpha-glucosidase in the small intestine were suggested as possible mechanisms related with the postprandial hypoglycemic effect of MLE.

Changes in Lymphocyte DNA Damage and Antioxidant Status after Supplementing Propolis to Korean Smokers: A Placebo-Controlled, Double-Blind Cross-Over Trial

Smoking has been known to exacerbate the initiation and propagation of oxidative stresses. Efforts have been made to reduce the smoking-induced oxidative stresses using commercial dietary supplements. Propolis is the resinous substance collected by bees from the leaf buds and bark of trees, especially poplar and conifer trees. In this trial, we examined whether a daily supplementation of 800 mg propolis can protect endogenous lymphocytic DNA damage and modulate antioxidative enzyme activities and the level of antioxidant vitamin in smokers using a placebo-controlled, double-blinded cross-over trial. After two weeks of running-in period, 29 smokers (mean age 34.38 +/- 1.73) received 6 tablets/day of either propolis or placebo pills for 4 weeks. After 2 weeks of washout period the subjects switched they pills for cross-over study. The degree of DNA damage (assessed by tail DNA, tail length and tail moment) was not significantly changed with propolis intake or placebo intake. Similarly, total antioxidant status (TAS) remained at the same level regardless of the treatment. Erythrocyte catalase, glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), plasma vitamin C and tocopherol level did not differ before and after propolis treatment, and did not differ between treatments. Putting all these results together, we would suggest that it is still too early to claim that propolis possess antioxidative activities.