Antioxidant Vitamin Intake in Dyslipidemic Overweight Individuals

Mailing Address: Gláucia Maria Moraes de Oliveira Rua João Lira – 128, 101. Postal Code 22.430-210, Leblon, Rio de Janeiro, RJ – Brazil E-mail: glauciamoraesoliveira@gmail.com Antioxidant Vitamin Intake in Dyslipidemic Overweight Individuals Mauara Scorsatto1, Glorimar Rosa2, Gláucia Maria Moraes de Oliveira1,2 Departamento de Medicina1, Universidade Federal do Rio de Janeiro; Instituto de Nutrição Josué de Castro2, Universidade Federal do Rio de Janeiro, RJ – Brazil


Introduction
It is estimated that 100 million inhabitants of 11 countries face the challenge of chronic non-transmissible diseases, which account for 57 million deaths per year, 80% of which occur in low-and intermediate-income countries, which have high prevalence of obesity, inappropriate nutrition and cardiovascular diseases (CVD).2][3] Currently the relationships of obesity and dyslipidemia with oxidative stress, longevity and reduction in mortality due to chronic diseases, especially CVD, are discussed. 4etary habit is considered an important strategy in CVD prevention.The intake of antioxidant vitamins, mainly vitamins A, C and E, promotes a reduction in the harmful effects of reactive oxygen species, reducing the incidence of CVD. 2 However, there is some evidence of the benefit of supplementation with antioxidants and vitamins for the treatment of chronic diseases, such as obesity and diabetes. 5rculating levels of carotenoids, vitamins A and C, zinc, magnesium and selenium were inversely correlated with obesity and body mass, being associated with visceral adiposity; the causality relationship, however, cannot be inferred from the intervention studies available. 6Vitamin E prevented the proliferation of lipid peroxidation, affecting the concentrations of F2-isoprostanes and reducing the extension of arterial wall lesions. 7e relationship between dietary intake, especially of fats and vitamins, and oxidative stress, measured via F2-isoprostanes, is still controversial, depending on the heterogeneity of the populations studied and the methods used. 8e present study aimed at assessing the dietary intake of antioxidant vitamins A, E and C, and of macronutrients, and at correlating them with anthropometric and biochemical markers in dyslipidemic obese or overweight individuals in the municipality of São Gonçalo, Rio de Janeiro state.

Population studied
A cross-sectional study was conducted with adults recruited via posters placed at health care centers in the municipality of São Gonçalo, Rio de Janeiro state.This study was approved by the Ethics Committee of the Clementino Fraga Filho university-affiliated hospital (Federal University of Rio de Janeiro/Brazil), n° 062/10.All study participants provided written informed consent.
This study included dyslipidemic individuals of both sexes, aged ≥20 years, with body mass index (BMI) ≥25 kg/m 2 and at least one of the following laboratory changes: low-density lipoprotein cholesterol (LDL-C) ≥160 mg/dL; triglycerides (TGs) ≥150 mg/dL; highdensity lipoprotein cholesterol (HDL-C: men < 40 mg/dL, women < 50 mg/dL). 9The following individuals were excluded: smokers, pregnant women, breastfeeding women, individuals on diets and/or anorectic drugs or on supplements of any nature.

Anthropometric assessment
Body mass was measured with an electronic scale (Welmy), 200 kg maximum capacity and 50 g accuracy.Height was measured with a 2.0 m stadiometer coupled to the scale.The BMI was calculated according to the World Health Organization recommendation. 9Waist circumference (WC) was measured with an inelastic tape, at the mid-point between the iliac crest and the lowest rib, 10 and body composition was assessed via bioimpedance (BIODYNAMICS 450, USA).

Biochemical analyses
Blood samples were collected after a 12-hour night fasting, in tubes with or without ethylenediaminetetraacetic acid (Vacutainer®, BectonDickinson, NJ).Serum and plasma aliquot portions were obtained by use of centrifugation at 4000 rpm for 15 minutes (Excelsa Baby I centrifuge; Fanem, São Paulo, Brazil) and stored at -80 °C until the analyses.The serum concentrations of total cholesterol, HDL-C and TGs were determined using an enzymatic colorimetric method in the LABMAX 240 automatic biochemical analyzer (Labtest Diagnóstica S.A, Brazil).The LDL-C concentrations were calculated with the Friedewald formula. 11The plasma concentrations of F2-isoprostane were determined by using ELISA with Cayman kit (USA).

Assessment of food intake
Usual food intake was assessed by using the food frequency questionnaire (FFQ). 12The household measurements of food were registered in the FFQ and converted into grams according to Pacheco (2006). 13The chemical composition of the diet was assessed by use of the Food Processor software, version 12.The daily energy requirement, as well as the appropriateness of each participant's intake, was calculated with the Dietary Reference Intake equations. 14.

Statistical analysis
Descriptive data analysis was performed.The normality of the variables was assessed with nonparametric Kolmogorov-Smirnov test and Spearman correlation.Data were expressed as mean ± standard deviation or median and percentile, as appropriate.Analyses were performed with the statistical software SPSS, version 18.The significance level adopted was p < 0.05.

Results
Of the 363 individuals selected, 79 were not dyslipidemic, being excluded.Therefore, this study included 284 individuals as follows: 264 women (93.1%) and 20 men (7.04%).Because of the small percentage of male participants, the results were not discriminated by sex.
The means of age, BMI and WC were 45.4 ± 11.2 years, 36.0 ± 5.8 kg/m 2 and 106.2 ± 12.7 cm, respectively.Regarding the educational level, 24% of the participants had elementary education (complete or incomplete), 45.4% had complete secondary education, and only 12.3% had complete higher education (Table 1).It is worth noting that the mean and median WC values in men, 112.7±8.1 cm and 112.0 cm (P25= 106.1 cm; P75= 117 cm), respectively, were higher than the values considered within the normal range.The same occurred with the HDL-C levels (mean= 37.2±8.3mg/dL; median= 35 mg/dL, P25= 33, P75= 39).
Table 2 shows the dietary data of the population studied.Added sugar intake was three times the maximum recommended value of 10% of the total energy value (TEV).The ratio between vitamin E and polyunsaturated FA intake was greater than 0.4 mg of alpha-tocopherol/g of polyunsaturated FA; however, that result was not necessarily positive, because both vitamin E and polyunsaturated FA intake was below 50% of appropriateness.Fiber intake, however, was above the daily value recommended, being an important protective finding.

Original Article
Table 3 shows Spearman correlation between anthropometric, dietary and biochemical variables and body composition.There was a significant correlation of total cholesterol and HDL-C with carbohydrates, proteins, polyunsaturated FA and dietary fibers.As expected, there was a positive correlation of BMI and WC with fat mass and fat-free mass; however, negative correlation was observed between the latter and total cholesterol and its fractions.There was a positive correlation between vitamin A and per capita income, and a negative correlation between vitamin E and total cholesterol and LDL-C.

Discussion
In this study, the mean refined sugar intake was three times that recommended, and the mean total fat intake was below that recommended; however, the saturated and trans FA intakes were greater than the recommended values.[17] In this study, 99.3% of the individuals had WC corresponding to the "increased risk" classification for men and women (mean and median, 106 cm).Fat accumulation in the abdominal region favors the prevalence of dyslipidemia, hypercholesterolemia and hypertriglyceridemia. 18 A study with obese individuals of both sexes undergoing a low-fat and hypocaloric diet or hypocaloric or low-carbohydrate Mediterranean diet (higher proportion of monounsaturated FA/saturated FA) without energy restriction, but avoiding trans FA, has concluded that a low-carbohydrate diet, but without fat and protein restriction, was the most beneficial one, because it enhanced the HDL-C/LDL-C ratio. 19Replacing saturated FA with polyunsaturated FA is considered the best choice, because it can reduce LDL-C, increase the HDL-C/LDL-C ratio, reduce the total cholesterol/HDL-C ratio, reduce the risk for CVD 20 and have a beneficial effect on ischemic heart disease; however, it can reduce HDL-C. 19Such results are similar to those of the present study, in which polyunsaturated FA intake correlated negatively with total cholesterol, LDL-C and HDL-C serum levels.In addition, the relatively low intake of polyunsaturated FA, in association with the relatively high intake of carbohydrates (65% of TEV), seems to lead to hypertriglyceridemia and low HDL-C concentrations, predisposing to cardiovascular events. 21 the treatment of hypercholesterolemia, dietary cholesterol seems to have little influence on cholesterol concentration and early atherosclerosis. 2Only around 30% of the population can benefit from the decrease in cholesterol intake, such a individuals with diabetes, whose mechanism of cholesterol transportation can have abnormalities. 2 In the present study, although the mean dietary cholesterol intake was above that recommended for dyslipidemic individuals, no positive correlation with serum cholesterol was observed.
Of the antioxidant vitamins, vitamins E and A are carried with LDL-C particles, preventing the modification of those particles by oxidation. 2Although the mean dietary intake of vitamin E in this study reached only 41% of the recommended values, it correlated negatively with the serum concentrations of total cholesterol and LDL-C.A well-established mechanism of action of alpha-tocopherol (vitamin E) is its reaction with the alkylperoxyl radical.Alpha-tocopherol interrupts the chain reaction of lipid peroxidation, stealing alkylperoxyl radicals. 22veral biomarkers have been proposed to measure lipid peroxidation, mainly F2-isoprostanes, whose levels would be high in vitamin E depletion.In the present study, however, the plasma levels of F2-isoprostanes were within the normal range of 5-50 pg/mL, which can be due to two reasons: first, several months of vitamin E depletion are required before any significant drop occurs in the concentration of circulating tocopherol; and second, F2-isoprostane is not a specific marker of vitamin E, and other antioxidants can have similar effects. 6 the present study, vitamin A correlated negatively with per capita income, considering that liver, milk fat and eggs are the major sources of vitamin A. Possibly, the lower the income, the higher the consumption of those foods, and, as the income increases, individuals have access to other foods, as observed in the ELSA-Brasil study. 16Vitamin C is the most versatile and effective hydrosoluble dietary antioxidant, because it can donate electrons to be stolen by a variety of oxidant and reactive species; in addition, it protects the organism against lipid peroxidation. 6 The study by Fernandes et al. 23 has shown high prevalence of inappropriate dietary intake among adults, especially of vitamins A, E and C.Those authors have concluded that their findings point to the need for an appropriate dietary planning, especially regarding those micronutrients, considering that lipid profile changes and high overweight/obesity prevalence are associated with an increase in oxidative stress, and, consequently, with higher use of antioxidant nutrients.
The assessment of antioxidant dietary intake and its association with the lipid profile of adults with BMI > 25 kg/m 2 has shown that the mean intake of vitamins C, E and A was below the recommended values (23.7%, 65.8% and 55.3%, respectively). 24In the present study, the dietary intake of vitamins A and C exceeded the recommended values.Only the vitamin E intake was below the recommendation, not reaching 50% of it.
It is worth emphasizing that many randomized studies with a large number of patients, and using antioxidants, such as vitamins A, C and E, have not shown benefits in the prevention of chronic diseases; therefore, their supplementation in the current therapeutic strategy is not recommended for all patients.However, antioxidants can be beneficial if the intervention is performed in specific subgroups. 25evertheless, it is worth noting the need for the implementation of a healthy lifestyle, such as the intake of several daily portions of vegetables and fruits combined with physical activity practice, to decrease the outcomes associated with chronic diseases. 26

Conclusion
The population studied showed inappropriate vitamin E intake, which correlated negatively with total cholesterol and LDL-C levels.The intakes of vitamins A and C were higher than the dietary recommendations, requiring an individualized approach to define treatment strategy, to improve the quality of life and reduce costs of several sectors.Rosa G. Statistical analysis: Scorsatto M, Oliveira GMM.Obtaining financing: Rosa G, Oliveira GMM.Writing of the manuscript: Scorsatto M, Oliveira GMM.Critical revision of the manuscript for intellectual content: Scorsatto M, Rosa G, Oliveira GMM.Submission: Oliveira GMM.

Potential Conflict of Interest
No potential conflict of interest relevant to this article was reported.

Sources of Funding
This study was funded by Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) e pela Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES).

Study Association
This article is part of the thesis of Doctoral submitted by Mauara Scorsatto, from Faculdade de Medicina da Universidade Federal do Rio de Janeiro.

Table 2 Percentiles and appropriateness of major dietary variables
* The parameters of the IV Brazilian Guideline on Dyslipidemias and Atherosclerosis Prevention (SBC) were used to calculate the % appropriateness, considering the following maximum values: protein ≤15% of TEV; carbohydrate 50-60% of TEV; dietary fiber 20-30 g; soluble fiber 6 g; sugar <10% of TEV; total fat 25-35% of TEV; saturated fatty acids (FA) ≤7%; monounsaturated FA ≤20% of TEV; polyunsaturated FA ≤10% of TEV; trans FA <1% of TEV; cholesterol ≤200 mg.The Dietary Reference Intakes (DRI) were used according to the Institute of Medicine ++ to calculate appropriateness: vitamin A 900 mcg; vitamin C 90 mg; vitamin E 15 mg.