Docosahexaenoic acid (DHA) during pregnancy reduces childhood obesity

 

Babies born to mothers who eat the recommended quantity of  DHA during pregnancy are 32 percent less likely to have excessive body fat indicative of potential obesity1. That’s the latest results from a population based study just published in the American Journal of Clinical Nutrition highlighting the benefits of eating fish and omega -3 long chain polyunsaturated fatty acids (LC-PUFAs) such as DHA derived from fish oils.

The study included 1120 pregnant women whose fatty acid intake was measured mid-pregnancy.  At the time of birth, a portion of those women had their plasma concentration of fatty acids (n=227) and umbilical cord blood fatty acids (n=302) quantified.  The composition of cord blood is indicative of the infant’s status. After three years, their infant’s degree of adiposity (fat accumulation) was measured using a combination of subscapular (under the shoulder blade) and triceps (back of the arm) skinfold thickness and body mass index (BMI).  The risk of obesity was defined as a BMI of >/= 95th percentile for age and sex.  In addition, the infant’s blood leptin concentration was measures.  Leptin levels increase with increase in body fat accumulation.

The results showed that only 3% of the women consumed the recommended daily intake of 200 mg DHA during the last month of pregnancy – the time when the largest amount of DHA is being transferred from the mother to the fetus.  The likelihood of obesity was 2-4 times higher when cord blood had a high ratio of omega-6 to omega-3 LC-PUFAs.  The odds of obesity were 32% lower when maternal consumption of omega-3 LC-PUFAs was high or if the ratio of omega-3 to omega-6 LC-PUFAs was at close to recommended levels. However, higher maternal intake and cord blood concentrations of total omega-6 were generally not significantly associated with adiposity outcomes. Therefore, the increase in obesity risk was attributed to insufficient omega-3 intake rather than too much omega-6.

Low intake of omega-3 fatty acids derived primarily from fish in addition to the presence of a large amount of omega-6 fatty acids found in abundance in vegetable oils has been suggested to be a risk factor in the development of obesity. However, this study showed that body fat accumulation reflects a lower omega-3 LC-PUFA status and a lower ratio of omega-3 to omega-6 rather than a higher omega-6 LC-PUFA status.

Previous studies on the effects of omega-3 LC-PUFAs during pregnancy and/or while breast feeding on the infant have focused primarily on brain/eye development and function.  They have shown that higher maternal DHA status at birth is associated with enhanced attentional functioning in the toddlers during their first and second years of life3,4.  Earlier reports have shown that the concentration of DHA in umbilical cord blood is a good indicator of foetal exposure to that nutrient during the last trimester of pregnancy and that a higher concentration of DHA in infant cord blood increases gestation, improves visual acuity and intelligence at 6 months of age, and also increases mental and psychomotor development at 11 months of age5.  A trial including term infants showed the quality of movement was dependent on how high the infants DHA was at the time of birth and was independent of gender, cognitive performance, gestational age and age at measurement6.  Earlier in 2007, a similarly designed study showed that low infant blood levels of DHA predict the development of internalizing problem behaviour later in life7.  A 2009 study reported that babies born to mothers who took DHA during pregnancy and while breast feeding are 7.5 times less likely to develop food allergies and 3 times less likely to develop eczema.The largest clinical study ever providing DHA to 2,399 pregnant women reported a 60% reduction in slow developing cognitive and language skills in infants, a 35% reduction in the incidence of low birth weight babies and 50% reduction in the number of very early pre-term deliveries with no serious adverse effects for either the mother or infant9.

Other clinical studies have shown that maternal fish intake during pregnancy is associated with higher IQ in offspring8, and that pregnant mothers taking DHA rich fish oil supplements during the last trimester can maintain their DHA status.10 In addition, infants born to these mothers have also been shown to start life with higher DHA levels than those of mothers who were not supplemented.10 Infants with higher DHA status have enhanced sleep patterns suggesting greater central nervous system maturity11, enhanced attention and mental processing4, score better in mental processing tests12,  have higher IQs at four years of age13 and higher scores for language comprehension, average phrase length and vocabulary14.   All good reasons for a mother to ensure she is getting enough DHA during pregnancy.

References:

1. Donahue SMRifas-Shiman SLGold DRJouni ZEGillman MWOken E. Prenatal fatty acid status and child adiposity at age 3 y: results from a US pregnancy cohort.Am J Clin Nutr. 2011 Apr;93(4):780-8. Epub 2011 Feb 10.

2. Furuhjelm C, Warstedt K, Larsson J et al. Fish oil supplementation in pregnancy and lactation may decrease the risk of infant allergy. Acta Paediatr 2009 Jun 1 [Epub ahead of print]

3. Kannass KN, Colombo J, Carlson SE. Maternal DHA levels and toddler free-play attention. Dev Nauropsychol2009;34(2):159-74.

4. Colombo J, Kannass KN, Shaddy DJ, et al. Maternal DHA and the development of attention in infancy and toddlerhood. Child Dev. 2004;75(4):1254-67.

5. Jacobson JL, Jacobson SW, Muckle G, Kaplan-Estrin M, Ayotte P, Dewailly E. Beneficial effects of a polyunsaturated fatty acid on infant development evidence from the Inuit of Arctic Quebec. J Pediatr  2008;152:356-64.

6. Bakker EC, Hornstra G, Blanco CE, Vles JS. Relationship between long-chain polyunsaturated fatty acids at birth and motor function at 7 years of age. Eur J Clin Nutr. 2007 Dec 19; doi:10.1038/sj.ejcn.1602971.

7. Krabbendam L, Bakker E, Hornstra G, vanOs J. Relationship between DHA status at birth and child problem behavior at 7 years of age. Prostaglandins Leukot Essent Fatty Acids 2007;76:29-34.

8. Hibbeln JR, Davis JM, Steer C, Emmett P, Rogers I, Williams C, Golding J. Maternal seafood consumption in pregnancy and neurodevelopmental outcomes in childhood (ALSPAC study): an observational cohort study. Lancet 2007;369:578-585.

9. Makrides M, Gibson R, McPhee A, Yelland L, Quinlivan J et al. Effect of DHA supplementation during pregnancy on maternal depression and neurodevelopment of young children. JAMA  2010;304(15):1675-1683.

10. Van Houwelingen AC et al. EFA status in neonates after fish oil supplementation during late pregnancy. Br J Nutr 1995: 74(5):723- 31.

11. Cheruku et al. Higher maternal plasma DHA during pregnancy is associated with more mature neonatal sleep-state patterning. Amer J Clin Nutr 2002;76:608-13.

12. Decsi T and Koletzko B.  N-3 fatty acids and pregnancy outcomes. Curr Opin Clin Nutr Metab Care. 2005:8(2)161-6.

13. Helland et al. Maternal supplementation with very long chain n-3 fatty acids during pregnancy and lactation augments children’s IQ at 4 years of age. Pediatrics 2003 Jan;111(1):e39-44.

14. Dunstan J, Simmer K, Dixon G, Prescott S. Cognitive assessment of children at age 2.5 years after maternal fish oil supplementation in pregnancy: a randomized controlled trial. Archives of Disease in Childhood: published online ahead of print: 10.1136/adc.2006.099085.