Iodine is an essential element trace for the synthesis of maternal thyroid hormones needed to support normal fetal development; it also acts as an antioxidant directly or induce antioxidant enzymes indirectly. Iodine deficiency and oxidative stress are associated with pregnancy complications. This study aimed to assess the urinary iodine concentration and its relationship with the antioxidant and oxidative stress status during gestation. Pregnant women were consecutively recruited from an obstetric clinic during all gestation trimesters, and urinary iodine concentration, antioxidant, and oxidative stress were determined. Results showed that 70 % of pregnant women have optimal iodine levels (150-200 μg/L), while approximately 30 % showed mild iodine deficiency (50-99 μg/L). Oxidative stress was significantly higher, and the antioxidant status was also compromised as evidenced by decreased total antioxidant status and superoxide dismutase (SOD) activity in pregnant women with mild iodine deficiency than pregnant women with optimal iodine levels. Significant positive correlations were noted between optimal iodine levels and total antioxidant status. Oxidative stress was significantly correlated with mild iodine deficiency. However, no significant correlation was found between iodine levels and SOD and catalase activities. In conclusion, for the first time, these data suggest a correlation between iodine levels and the antioxidant status during pregnancy.

The prevalence and incidence of overweight and obesity worldwide continues to increase, as well as diseases related to these conditions. This is attributed to an increase in energy intake and a decrease in energy expenditure. Consumption of green tea has been linked to a reduction in body fat and body weight. However, research on green tea has been very diverse. This review assesses the investigations that have been made with green tea and its epigallocatechin gallato (EGCG) content, evaluating its effect on body fat and body weight in humans. A search was made in the PubMed and Web of the Science databases that gave a first total result of 424 potential articles; 409 were excluded and 15 articles were used for this systematic review. Research has been very varied, however, daily consumption of green tea with doses of EGCG between 100 and 460 mg/day has shown greater effectiveness on body fat and body weight reduction in intervention periods of 12 weeks or more. In addition, the use of caffeine doses between 80 and 300 mg/day has been shown to be an important factor for this effects, when the participants did not have a high caffeine intake (> 300 mg/day) prior to the intervention.

alteration in IL-1, adiponectin and oxidative stress levels were found to be related to overweight and obesity; also, iodine levels decreased when BMI increased, contributing to loss of redox equilibrium. All this data may play an important role in etiopathogenesis of chronic disease related to the increase of BMI.

Obesity and overweight are among the major health problems in the world today. The excessive accumulation of fat in adipose tissue is accompanied by low-grade inflammation, adipokine secretion dysregulation, oxidative stress, and an alteration of the secretion of gut hormones and food intake related to peptides. This is related to the development of cardiovascular diseases, which have been increased worldwide during the last years approximately. The biomarkers are tremendously important to predict, diagnose, and observe the therapeutic success of common complex multifactorial metabolic diseases, such as obesity and cardiovascular diseases. This chapter presents a review of the most common biomarkers that have been used in the prevention, treatment, prognosis, and diagnosis of obesity and cardiovascular diseases.Keywords: biomarkers, cardiovascular disease, obesity, genetic markers, serum markers . Introduction . . Overweight and obesityObesity and overweight have greatly become a stigma in most of the countries around the world since the middle of the past century, depending on the location, but it was not recognized as a disease until [ ]. Its presence and the difficulty to eradicate it, it is mainly due to the multifactorial nature of this trait that depends on genetic and environmental factors as well as stimuli, learning, reward, and representation of food processing at high centers of the nervous system, which results in an increase of energy intake and subsequently body "ody mass index "MI is a measure of weight adjusted to height and calculates weight as in kilograms divided by the square of height in meters kg/m . "lthough "MI is often considered an indicator of body fatness, it is a surrogate measure of body fat because it measures excess weight rather than excess fat. Despite this fact, studies have shown that "MI is correlated with more direct measures of body fat, such as underwater weighing and dualenergy X-ray absorptiometry. The clinical limitations of "MI should be considered. Factors such as age, sex, ethnicity, and muscle mass can influence the relationship between "MI and body fat [ ]. Considerable literature has grown up around the theme and suggests that other measures of body fat, such as skinfold thicknesses, bioelectrical impedance, and/or dual- Role of Biomarkers in Medicine 120energy X-ray absorption may be more accurate than "MI, for example, waist circumference sometimes divided by height is a simple measure of fat distribution. The main problem of standardization is that the cost of it tends to be highly overpriced, intrusive, not widely available, or difficult to standardize across observers or devices. Therefore, the procedures previously mentioned are considered not suitable for a regular physician exercise purpose. In addition, most of the literature concerning obesity health risks is based on several "MI studies and their outcomes, yet there are not enough standardized frames to calculate body fatness which may compromising the measurement of the fat amount that an indiv...

Total energy expenditure (TEE) has three components: basal expenditure, physical activity expenditure, and diet-induced thermogenesis (DIT). This last component, although represents 10% of TEE, if is altered, could have a long-term effect on body weight. Different factors have been shown to influence DIT, including diet composition. However, other factors such as feeding frequency and schedules have been studied for their role in altering DIT. This systematic review explores the research regarding the frequency and timing of feeding and its effect on DIT in humans. A search was made in the PubMed and Web of Science databases, which gave a total of 542 potential articles; 528 were excluded and 14 articles were used for this systematic review in accordance with the inclusion criteria. Although the results are still incipient, the effect of the circadian rhythms that influence the increase of the DIT in response to the morning meal when comparing it with night, as well as the increase in the DIT after the implementation of regular feeding frequencies and decreased DIT after the variable feeding frequencies, stand out. Finally, a tendency to increase in the DIT when the interprandial periods are equal to or greater than two hours and a decrease when these periods are less than two hours were also observed. These results point to a research field with therapeutic potential in the prevention and control of overweight and obesity.