Lecture 6 - Maternal Nutrition During Pregnancy Flashcards
pregnancy is considered a what state
anabolic state
during pregnancy, hormonal changes alter nutrient metabolism to support :
- fetal growth and development
- reproductive tissue accretion
- maternal homeostasis
what happens to basal energy expenditure (BEE) during pregnancy
increase over the non pregnant state due to added metabolism of uterus and fetus increased work of the maternal heart and lungs
what happens to the thermic effect of food during pregnancy
remains unchanged
what happens to the energy cost of physical activity during pregnancy
energy cost remains the same
what is equivalent to total energy expenditure
- basal energy expenditure
- thermic effect of food
- physical activity
what is the recommended energy intake during the first trimester of pregnancy
extra energy not required
what is the recommended energy intake during the second trimester of pregnancy
1,400kJ/day added to estimated energy requirement of non pregnant women
what is the recommended energy intake during the third trimester of pregnancy
1,900kJ/day added to estimated energy requirement of non pregnant women
what are linoleic (18:2n-6, LA) and a-linolenic acid (18:3n-3, LNA) and what are they used to make
essential fatty acids omega 3 and omega 6, used to make LCPUFA’s
what is desaturation of LCPUFAs
inserting of double bonds into the fatty acid chain
what are LCPUFAs
long chain polyunsaturated fatty acids
what is elongation of LCPUFAs
adding two carbon atoms onto the carboxyl end of the fatty acid chain
what is desaturation of LCPUFAs catalysed by
desaturase enzyme
what is elongation of LCPUFAs facilitated by
elongase enzyme
what are LCPUFAs essential for
for normal fetal development, particularly neural and visual function
endogenous synthesis of AA is far more effective than …
DHA
what is DHA (LCPUFAs)
a critical component of cell membranes, especially in the brain and retina
what is AA (LCPUFAs)
both a membrane component and a precursor to potent signalling molecules, the prostaglandins and leukotrienes (mediate inflammatory response)
how does n-3 fatty acid deposition in the developing fetal brain and retina occur
initially occurs fairly slowly and then rapidly accumulates during the last trimester
why is the fetus dependent on placental supply for both LCPUFAs and essential fatty acids
the fetus has active desaturases but limited ability to make LCPUFAs
what influences the cord blood concentrations of LCPUFAs
maternal diet
in NZ most of us get enough of what essential fatty acid but we get less of what one
most of us get enough of linoleic acid (omega 6) but we get less of a-linoleic acid (omega 3)
a rich supply of n-3 fatty acids during pregnancy is associated with what
reduced incidence of low birth weight
higher DHA and / or EPA intake during pregnancy increases
increases gestational age and heavier infants (better healthy weight)
why do maternal and fetal fatty acid requirements during pregnancy depend on maternal genetic variation in LCPUFA synthesis
because it was found FADS (homozygous minor allele) had shorter pregnancies and lighter infants
a meta-analysis found that omega-3 intake during pregnancy reduced risk of
peanut and egg allergy
what is monomethylmercury
occurs naturally in the environment and in industrial pollution accumulating in streams and seas
monomethylmercury is taken up by what
taken up by aquatic organisms and concentrated in fish