1.Oxidative Stress in Early Life and Later Obesity Development
Loy SL ; Sirajudeen KNS ; Hamid Jan JM
Malaysian Journal of Nutrition 2013;19(3):383-399
Introduction: Critical time windows exert profound influences on foetal physiological and metabolic profiles, which predispose an individual to later diseases via a 'programming' effect. Obesity has been suggested to be 'programmed' during early life. Foetuses and infants who experience adverse growth are subjected to a higher risk of obesity. However, the key factors that link adverse foetal growth and obesity risk remain obscure. To date, there is considerable evidence showing that the overall balance between free radical damage and the antioxidative process being challenged occurs throughout gestation. With the view that pregnancy is a pro-inflammatory state confronted with enhanced oxidative stress, which possesses similar characteristics to obesity (a chronic inflammatory state with increased oxidative stress), oxidative stress is thus biologically plausibly be proposed as the underlying mechanism between this causal-disease relationship. Oxidative stress could act as a programming cue for the development of obesity by inducing complex functional and metabolic deregulations as well as inducing the alteration of the adipogenesis process. Thereby, oxidative stress promotes adipose tissue deposition from early life onwards. The enhancement of fat accumulation further exaggerates oxidative derangement and perpetuates the cycle of adiposity. This review focuses on the oxidative stress pathways in prenatal and early postnatal stages, from the aspects of various endogenous and exogenous oxidative insults. Because oxidative stress is a modifiable pathway, this modifiability suggests a potential therapeutic target to fight the obesity epidemic by understanding the causal factors of oxidant induction.
2.Development, Validity and Reproducibility of a Food Frequency Questionnaire in Pregnancy for the Universiti Sains Malaysia Birth Cohort Study
Loy SL ; Marhazlina M ; Nor Azwany Y ; Hamid Jan JM
Malaysian Journal of Nutrition 2011;17(1):1-18
Introduction: This study aimed to develop and examine the validity and
reproducibility of a semi-quantitative food frequency questionnaire (FFQ) among
Malay pregnant women in Kelantan, Malaysia. Methods: A total of 177 Malay
pregnant women participated in the validation study while 85 of them
participated in the reproducibility study which was carried out in the antenatal
clinic of Universiti Sains Malaysia Hospital. The newly developed FFQ was
validated against two 24-hour dietary recalls (DR). The FFQ was repeated 20 to
28 days apart. Results: Results showed that the FFQ moderately over estimated
the nutrient and food intakes compared to the DR. Spearman correlation
coefficients for nutrients ranged from 0.24 (fat) to 0.61 (calcium) and for foods,
ranged from 0.13 (organ meats, onion and garlic) to 0.57 (malt drink). For
nutrients, 72 to 85% of women were classified into the correct quartiles from the
FFQ and the DR while for foods, 67 to 85% of women were classified correctly.
Bland-Altman plot showed relatively good agreement between these two dietary
methods. The intra-class correlation (ICC) was used to estimate reproducibility.
It ranged from 0.75 (vitamin C) to 0.94 (phosphorus) for nutrients while it ranged
from 0.73 (confectionary) to 0.96 (coffee) for foods. Conclusion: On average, at
least 90% of pregnant women were correctly classified into the quartiles for
nutrients and foods from the two sets of the FFQ. The FFQ presented acceptable
reproducibility and appears to be a valid tool for categorising pregnant women
according to dietary intake.