Maternal energy requirements increase during pregnancy due to higher basal energy expenditure as well as energy deposition in maternal and fetal tissues. Basal metabolism of the mother is higher due to the increased work by the lungs and heart and because of the metabolism of the fetus and uterus. A longitudinal study by Butte et al. found that basal metabolic rate increased by 10.7 ± 5.4 kcal per week of gestation, mostly in the second and third trimesters. On average, the fetus requires approximately 168 kcal/day. The substantial variability in basal energy expenditure among individual women is caused mainly by differences in fat-free mass (including maternal skeletal muscle mass and fetal tissue). The cumulative increase in basal energy expenditure during pregnancy is positively correlated with maternal fatness and weight gain. Energy requirements for the thermic effect of feeding are not different from those of nonpregnant women, nor is there much change in the total energy cost of activity. Although the increasing body weight of the mother means that the energy cost of each activity is higher, the net effect is cancelled out by the fact that after approximately 25 weeks of gestation

Table 1 Recommended Dietary Allowances (RDAs) for nonpregnant and pregnant women and Estimated Average Requirements (EARs) and Upper Limits of nutrients for pregnant womena
How To Reduce Acne Scarring

How To Reduce Acne Scarring

Acne is a name that is famous in its own right, but for all of the wrong reasons. Most teenagers know, and dread, the very word, as it so prevalently wrecks havoc on their faces throughout their adolescent years.

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