Duygu Türközü

A minireview of effects of green tea on energy expenditure

ABSTRACT In recent years, individuals have begun to tend more frequently to some natural and herbal products to be used alone or as a combination with diet and exercise for ensuring the weight loss. Green tea is the leading one of these products. In some studies, it is reported that the green tea causes an increase in thermogenesis and substrate with fat oxidation by affecting on the sympathetic nervous system. It is reported that green tea has two main components that are associated with energy expenditure. One of them is caffeine and the other is catechin content. Each of these two components has an impact on energy mechanism separately. In this minireview article, mechanisms of action and effects of caffeine and catechin, which are found in green tea composition, on energy expenditure are assessed.

L-Theanin, Unique Aminoacid of Tea, and Its Metabolism, Health Effects, Safety.

ABSTRACT Tea has been a very popular beverage around the world for centuries. The reason that it is delicious, enabling hydration, showing warming and relaxing effect can be mentioned why it is consumed so much in addition to its prominent health effects. Although the catechins and caffeine are the primary bioactive components that are related with the health effects of the tea, the health effects of theanine amino acid, which is a nonproteinic amino acid special to tea, has become prominent in recent years. It has been known that the theanine amino acid in tea has positive effects especially on relaxing, cognitive performance, emotional status, sleep quality, cancer, cardiovascular diseases, obesity, and common cold. The results of acute and chronic toxicity tests conducted on the safety of theanine express that L-theanine is reliable in general even if it is consumed too much with diet. However, it has not revealed a clear evidence-based result yet regarding theanine metabolism, health effects, and its safety. Within this frame, chemical structure of theanine, its biosynthesis, dietary sources, metabolism, health effects, and safety are discussed in present study.

Body Image, Food Addiction, Depression, and Body Mass Index in University Students

ABSTRACT The relationship between body image, depression, food addiction and body mass index (BMI) and differences in these variables due to gender and field of education have not been studied extensively. This study was conducted on a total of 793 university students (20.19 ± 1.90 years). The Beck Depression Inventory, Yale Food Addiction, and Body Image Scale were used. It was determined that body image scores of females and individuals enrolled in health sciences programs were lower compared to those of males and those enrolled in the social sciences. There was a negative relationship between body image and depression and food addiction scores. There was a positive relationship between food addiction and depression scores, in addition to a positive relationship between food addiction and BMI.

Plasma orexin‑A and ghrelin levels in patients with chronic obstructive pulmonary disease: Interaction with nutritional status and body composition

Orexin-A and ghrelin are two important polypeptides that stimulate food intake, however, there is a lack of sufficient information concerning their plasma levels in patients with chronic obstructive pulmonary disease (COPD). The aim of the present study was to investigate the association between plasma orexin-A and ghrelin levels with food consumption and body composition in patients with stable phase COPD. In total, 40 patients (age, 44–80 years; male, 31; female 9) who were in the stable phase of COPD were included in the study. Blood samples for plasma orexin-A and ghrelin analysis were collected after 8–12 h of fasting; certain anthropometric measurements were obtained and a 24-h dietary recall was recorded. The mean plasma orexin-A levels in the male and female patients were 1.3±0.37 and 1.4±0.13 ng/ml, respectively, while the mean plasma ghrelin levels were 25.9±7.31 and 27.3±8.54 ng/ml, respectively. No significant correlation was observed between the body mass index and plasma orexin-A and ghrelin levels or between the plasma ghrelin levels and dietary nutrient intake (P>0.05). The plasma orexin-A levels were demonstrated to be higher in patients with a higher dietary total fibre intake (r=0.303, P=0.022). A similar correlation was observed between plasma orexin-A levels and dietary intake of soluble (r=0.033, P=0.029) and insoluble (r=0.335, P=0.024) fibre, as well as between the daily consumption of calcium and the levels of plasma orexin-A (r=0.065, P=0.046). Therefore, the results of the present study indicated that a positive correlation existed between dietary nutrient intake and plasma orexin-A levels in patients with COPD.

Consumers’ Opinions and Use of Food Labels, Nutrition, and Health Claims: Results from Turkey

ABSTRACT This study was conducted to reveal Turkish consumers’ (18–65 years residing 10 cities, n = 1200) opinions and use of food labels, nutrition, and health claims. The majority of both females and males (64.7%, 68.2%) seldom read food labels. Risk for not paying attention to food labels was increased 1.287-fold when the gender was male. The percentage of reading food labels increases as education and income levels of individuals increase (p < 0.05). Expiry dates of foods were the most frequent read item on labels (58.0%). Males mostly read information on label to learn the price of the food (71.0%) while females read it to learn the energy value of food (79.0%). Females had more knowledge on nutrition claims compared to males (p < 0.05). The nutrition claims, which were most frequently read by females and males, were trans fat free (23.5%, 21.0%) and low fat/fat free (23.3%, 20.5%). The claim organic was paid most attention on fruit and vegetables (52.0%). The claim “low cholesterol contributes to maintenance of cardiovascular-health” was the most common health claim read. In summary, Turkish consumer’s behaviour of reading labels and nutrition-health claims could change according to some sociodemographic factors and food products.

The prevalence of abdominal obesity is remarkable for underweightand normal weight adolescent girls

Background/aim: Obesity is a global public health challenge. This study was carried out in order to determine the prevalence of obesity and abdominal obesity in Turkish adolescent girls. Materials and methods: A cross-sectional study was conducted in a total of 1111 adolescent girls aged 12?18 years. The subjects were classified into four groups: underweight, normal, overweight, and obese. Abdominal obesity was defined according to waist circumference (WC) ≥ 90th percentile for Turkish adolescent population references (12-17 years) and waist-to-height ratio (WHtR) ≥ 0.5. Results: The prevalence of underweight was 17.4%, normal weight 68.5%, overweight 12.1%, and obese 2.0%. A total of 16.9% subjects were abdominal obese based on WC and 10.4% based on WHtR. When the four groups were evaluated in terms of abdominal obesity status, prevalence was 6.4% and 2.6% in the underweight, 14.6% and 5.8% in the normal, 60.0% and 37.3% in the overweight, and 88.8% and 77.3% in the obese groups according to WC and WHtR, respectively. Both WC (r: 0.332) and WHtR (r: 0.156) were positively correlated with age (P < 0.05). Conclusion: The prevalence of abdominal obesity was found at high levels for overweight and obese adolescents. It should be emphasized that abdominal obesity is a condition that should be considered for underweight and normal adolescents as well. Therefore, abdominal obesity should be regularly assessed for nonobese adolescents to prevent cardiovascular risks, metabolic syndrome, and other related disease.