Fish oil accelerates immune system maturation in infants
COPENHAGEN, DENMARK. Infants are born with an immature immune system. Important characteristics of the immature immune system are an inadequate ability to produce certain cytokines (hormones that activate the immune system), notably gamma-interferon and interleukin-2 (IL-2) and a preponderance of Th2 helper T-cells over Th1 helper cells. Th1 helper T-cells enhance the ability of the immune system to respond to virus, bacteria, fungi and parasites, while Th2 helper T-cells are involved in allergic reactions and, if overactive, can cause inflammation such as seen in rheumatoid arthritis. Th2 cells release interleukin-6 (IL-6), excessive amounts of which are associated with allergic reactions and autoimmune disorders such as wheezing and asthma.
Healthy maturation of the infant’s immune system would thus involve increased production of gamma-interferon and/or IL-2 and an increase in Th1 cells to improve the ratio of Th1 to Th2 cells. Researchers at Copenhagen University report that supplementation with fish oil at age 9 months helps accelerate maturation.
Their study involved 64 healthy Danish infants who were fed either formula or cows’ milk for a 3-month period following cessation of breast-feeding. Half the children were also given a teaspoon (5 mL) of fish oil daily providing 571 mg/day of eicosapentaenoic acid (EPA) and 381 mg/day of docosahexaenoic acid (DHA). The infants had blood samples drawn at the beginning and end of the trial. Analyses of red blood cells showed a 450% increase in EPA and a 40% increase in DHA among infants who had supplemented with fish oil; these increases were accompanied by decreases in linoleic acid and arachidonic acid of 15%.
Whole blood samples were cultured and stimulated with various agents to provoke an immune response. The researchers noted a substantial increase in the production of gamma-interferon and a reduced production of interleukin-10 (IL-10) in the infants supplemented with fish oils. A reduced IL-10 production would indicate a dampened Th2 response to immune system provocation. Fish oil supplementation did not affect other markers of innate immunity or general inflammation (C-reactive protein and immunoglobulin E). The researchers conclude that daily fish oil supplementation between the ages of 9 and 12 months accelerates the maturation of infants’ immune systems and may be helpful in avoiding the development of allergic disorders.
Damsgaard, CT, et al. Fish oil supplementation modulates immune function in healthy infants. Journal of Nutrition, Vol. 137, April 2007, pp. 1031-36
DHA transfer during breast-feeding
COPENHAGEN, DENMARK. Long-chain polyunsaturated fatty acids, specifically arachidonic acid and docosahexaenoic acid (DHA), a major component of fish oil, are accumulated in the brain of the fetus and infant during the last trimester of pregnancy and the first year of life. DHA, in particular, has been found to be important for the development of the infant’s central nervous system and visual acuity. Although infants can, to a limited extent, convert alpha-linolenic acid to eicosapentaenoic acid (EPA) and DHA, by far the majority of the infant’s need for DHA must be met through mother’s milk or fortified infant formula. Danish researchers suggest that the transfer of DHA from mother to infant via breast milk may significantly deplete the DHA status of the mother.
Their study involved 12 mother/infant pairs who were enrolled within 30 days of birth. The study participants (both mothers and infants) provided blood samples 1, 2, and 4 months after delivery and mothers also provided samples of breast milk. The researchers found that the DHA content of the mothers’ red blood cells decreased significantly over the 4-month period, while that of the infants increased. It is not clear whether this is due to preferential transfer of DHA, or to differences in the metabolism and utilization of polyunsaturated fatty acids.
Jorgensen, MH, et al. The composition of polyunsaturated fatty acids in erythrocytes of lactating mothers and their infants. Maternal and Child Nutrition, Vol. 2, 2006, pp. 29-39
DHA declines during breast-feeding
MAASTRICHT, THE NETHERLANDS. Docosahexaenoic acid (DHA), a main component of fish oil, is an extremely important nutrient in the development of the brain of the fetus and infant. It is therefore not surprising that nature has ordained that blood plasma and red blood cell (erythrocyte) levels of DHA increase during pregnancy, possibly due to an enhanced conversion of docosapentaenoic acid to DHA. What is not known is how long it takes for DHA concentrations to return to pre-pregnancy levels, and whether the change is different in breast-feeding women than in those who feed their infants formula. Researchers at Maastricht University now provide an answer to these questions.
Their study involved 57 healthy women (average age of 30 years) who were recruited into the study after 36-37 weeks of pregnancy. The women gave birth after an average 40 week of pregnancy and were than followed for 64 weeks post-partum. Twenty-two of the women exclusively bottle-fed their infants, while the remaining 35 breast-fed. The fatty acid composition of plasma and erythrocytes was analyzed at entry to the study and then at regular intervals post-partum. Dietary intakes of fatty acids were assessed 4 and 32 weeks post-partum via validated food frequency questionnaires.
The researchers found that the total fatty acid content of plasma and erythrocytes decreased significantly post-partum, while the percentages of omega-3 fatty acids increased with the exception of DHA. DHA decreased steadily post-partum in both lactating and non-lactating women, but the decrease was substantially greater in breast-feeding mothers. The average daily intake of DHA at 32 weeks post-partum was 55 mg/day in non-lactating women and 81 mg/day in lactating women. However, it is estimated that the daily transfer of DHA in breast milk is about 51 mg, thus leaving only 30 mg/day for the breast-feeding women, likely not enough to cover their basic needs for this important fatty acid.
Otto, SJ, et al. Comparison of the peripartum and postpartum phospholipid polyunsaturated fatty acid profiles of lactating and nonlactating women. American Journal of Clinical Nutrition, Vol. 73, June 2001, pp. 1074-79
Maternal milk and DHA supplementation
MUNICH, GERMANY. Docosahexaenoic acid (DHA) is vital for the proper development of an infant’s brain and retina. DHA must be supplied through mother’s milk or infant formula as the infant itself is unable to synthesize it from other dietary sources such as flax oil. The DHA content of human milk varies from 0.05% in vegetarian women to 1.40% in Inuit women. An average level in omnivorous women is about 0.3% by weight. It is assumed that a mother’s diet affects the composition of her breast milk, but no specific studies of the transfer of DHA to breast milk has been made so far.
Researchers at the Ludwig-Maximilian-Universitat now report that an increased dietary intake of DHA by a lactating woman results in a proportional increase in her breast milk. Their study involved 10 lactating women who between week 4 and 6 postpartum supplemented with either 200 mg of DHA per day or 200 mg of a corn/soy oil mixture (placebo oil). At the end of the 2 weeks the DHA content of the milk from the DHA-supplemented mothers had increased by 28% while the DHA content in the milk from the mothers in the placebo group had decreased by 25%. In other words, after 2 weeks the DHA content in the milk from DHA-supplemented mothers was almost twice as high as in the milk from the mothers in the placebo group. There were no significant differences in the amount of milk produced per day by the 2 groups. Editor’s note: Supplementation with DHA would be particularly important for lactating mothers who are vegetarian.
Fidler, Natasa, et al. Docosahexaenoic acid transfer into human milk after dietary supplementation: a randomized clinical trial. Journal of Lipid Research, Vol. 41, September 2000, pp. 1376-83
Formula-fed infants need DHA
TORONTO, CANADA. A team of researchers from Canada, Britain, and the USA emphasize the importance of ensuring that newborn infants get sufficient docosahexaenoic acid (DHA) in order to ensure optimal neural and visual development during the first 6 months of life. They point out that there is still controversy as to whether the required DHA can be synthesized by the infants themselves (from alpha- linolenic acid) or must be supplied by the diet – be it breast milk or infant formula.
The researchers reviewed numerous studies comparing the DHA status of breast-fed infants with that of formula-fed ones. They found that over the first 6 months of life DHA accumulates in the body of breast- fed infants at a rate of 10 mg/day with 48% of this accumulation occurring in the brain. They estimate that an intake of 20 mg/day of DHA is required to achieve this accumulation and point out that breast feeding supplies about 60 mg/day. They believe the seeming over-abundance of DHA in breast milk may be needed in order to provide for potentially increased losses during disease, infection, surgery, and other conditions adversely affecting the infants’ metabolism.
On the other hand, formula-fed infants would seem to develop a serious deficiency of DHA if they are fed a formula which has not been fortified with DHA (usually in combination with arachidonic acid). Standard infant formulas contribute about 390 mg/day of alpha-linolenic acid so about 5.2% of this would have to be converted to DHA in order to produce the needed 20 mg/day. The researchers point out that there is no evidence at all that infants are able to achieve this conversion rate and speculate that the rate may be as much as 20 times lower than required. This conclusion is amply supported by the fact that formula-fed infants actually lose 993 mg of DHA over the first 6 months of life while breast-fed babies gain an average of 1882 mg. The accumulation of DHA in the brain of formula-fed infants is only half of that observed in breast-fed infants and while the liver in breast-fed infants gains 24 mg of DHA during the first 6 months the liver in formula-fed ones actually loses 136 mg.
The researchers conclude that feeding infants with a non-fortified formula will not provide the DHA provided by breast milk. They urge further work to determine whether a formula containing at least 0.2% DHA (providing 60 mg/day of DHA) will provide equivalent DHA accumulation to that of breast-fed infants.
Cunnane, Stephen C., et al. Breast-fed infants achieve a higher rate of brain and whole body docosahexaenoate accumulation than formula-fed infants not consuming dietary docosahexaenoate. Lipids, Vol. 35, January 2000, pp. 105-11
Docosahexaenoic acid fortifies breast milk
HOUSTON, TEXAS. Docosahexaenoic acid (DHA) is an important component of brain cell membranes; a deficiency during infancy has been linked to poorer brain development and a decline in visual acuity. DHA occurs naturally in breast milk, but is absent in most infant formulas. Surveys have shown that the DHA content in breast milk from American women tends to be lower than that in milk from women in most other countries. Researchers at the Baylor College of Medicine now report that the DHA content of breast milk can be increased by supplementing with DHA and that this higher DHA content is transferred to breast-fed infants. The study involved 26 pregnant women who planned to breast feed exclusively for at least eight weeks after giving birth. The women were randomly assigned to one of four groups and given a daily DHA supplement or placebo from two weeks after giving birth to eight weeks after giving birth. Group 1 received an algae-produced triacylglycerol with a high DHA content (providing less than 230 mg/day of DHA); group 2 consumed two high DHA content eggs (providing 170 mg/day of DHA); group 3 took a low EPA, high DHA fish oil (providing 260 mg/day of DHA); and group 4 (the control group) consumed two regular eggs daily (providing less than 35 mg/day of DHA).
All three forms of DHA supplements produced significant increases in the DHA content of the women’s blood plasma (phospholipid phase) and breast milk. Consumption of two eggs per day over a six-week period was well tolerated by all participants and had no adverse effects on cholesterol or triglyceride levels. The DHA level in the blood plasma (phospholipid phase) of the breast-fed infants also increased significantly over the six-week supplementation period with the infants in groups 1 and 3 having the largest increases. NOTE: This study was supported by a grant from the Mead-Johnson Nutritional Group. [61 references]
Jensen, Craig L., et al. Effect of docosahexaenoic acid supplementation of lactating women on the fatty acid composition of breast milk lipids and maternal and infant plasma phospholipids. American Journal of Clinical Nutrition, Vol. 71 (suppl), January 2000, pp. 292S-99S
Infants need long-chain omega-3 fatty acids
KANSAS CITY, MISSOURI. It is well-established that human infants require an adequate supply of omega-3 and omega-6 long-chain polyunsaturated fatty acids for optimal growth and neural development. There is evidence that the need for omega-3 acids, particularly docosahexaenoic acid (DHA), is especially pronounced among pre-term infants. It has been suggested that these infants lack the ability to synthesize DHA from alpha-linolenic acid in sufficient amounts to ensure an adequate supply to the brain and retina. Several studies have shown that pre-term infants fed a formula with added DHA developed better visual acuity and retinal response to light and scored higher when evaluated for mental development. In term infants some studies, but not all, have found higher visual acuity and better problem-solving ability in infants fed a DHA-containing formula.
Dr. S.E. Carlson of the University of Missouri supports the idea of adding DHA to infant formulas, but cautions that his fortification should be balanced with an appropriate addition of long-chain omega-6 acids (arachidonic acid) in order to more closely approximate the composition of mother’s milk.
Carlson, S.E. Long-chain polyunsaturated fatty acids and development of human infants. Acta Paediatr Suppl, No. 430, 1999, pp. 72-7
Your brain needs DHA
NEW YORK, NY. Dr. Barbara Levine, Professor of Nutrition in Medicine at Cornell University, sounds the alarm concerning a totally inadequate intake of DHA (docosahexaenoic acid) by most Americans. DHA is the building block of human brain tissue and is particularly abundant in the grey matter of the brain and the retina. Low levels of DHA have recently been associated with depression, memory loss, dementia, and visual problems. DHA is particularly important for fetuses and infants; the DHA content of the infant’s brain triples during the first three months of life. Optimal levels of DHA are therefore crucial for pregnant and lactating mothers. Unfortunately, the average DHA content of breast milk in the United States is the lowest in the world, most likely because Americans eat comparatively little fish. Making matters worse is the fact that the United States is the only country in the world where infant formulas are not fortified with DHA. This despite a 1995 recommendation by the World Health Organization that all baby formulas should provide 40 mg of DHA per kilogram of infant body weight. Dr. Levine believes that postpartum depression, attention deficit hyperactivity disorder (ADHD), and low IQs are all linked to the dismally low DHA intake common in the United States. Dr. Levine also points out that low DHA levels have been linked to low brain serotonin levels which again are connected to an increased tendency to depression, suicide, and violence. DHA is abundant in marine phytoplankton and cold-water fish and nutritionists now recommend that people consume two to three servings of fish every week to maintain DHA levels. If this is not possible, Dr. Levine suggests supplementing with 100 mg/day of DHA.
Levine, Barbara S. Most frequently asked questions about DHA. Nutrition Today, Vol. 32, November/December 1997, pp. 248-49
Docosahexaenoic acid helps brain development
MILAN, ITALY. Researchers at the University of Milan report that infants whose formula contains long- chain polyunsaturated fatty acids [especially Docosahexaenoic acid (DHA)] have better brain development than children who do not receive DHA in their formula. The observation supports earlier findings that there is a direct correlation between the DHA concentration in the red blood cells of infants and their visual acuity. The researchers recommend that infants who are not breastfed be fed on a DHA- enriched formula. Breast milk already contains the fatty acids necessary for good brain development.
Agostoni, Carlo, et al. Docosahexaenoic acid status and developmental quotient of healthy term infants. The Lancet, Vol. 346, September 2, 1995, p. 638
Maternal fish oil supplementation
Maternal DHA supplementation helps infant’s problem solving
BATON ROUGE, LOUISIANA. Maternal intake of DHA (docosahexaenoic acid) in the US and Canada is generally far below the currently recommend amount of 300 mg/day. This could have serious implications for the neurologic development of infants. Researchers at the Louisiana State University completed a study to determine if regular consumption by pregnant women of a cereal bar fortified with DHA would improve the problem-solving ability of their infants.
The double-blind, placebo-controlled trial included 29 women who were randomized to receive 5 DHA-fortified cereal bars a week (providing 214 mg/day of DHA and 27 mg/day of EPA) or placebo bars (containing corn oil) from week 24 of gestation to delivery. The women in the DHA group tended to give birth 1 week later than those in the placebo group and there was also a trend for their infants to be slightly taller.
At 9 months of age the infants participating in the trial were exposed to a problem-solving test involving finding and retrieving a toy. The infants born to mothers who had supplemented with DHA scored significantly higher on this test than did infants born to mothers who had not supplemented. A recognition memory test was also administered, but no differences in results were observed between the two groups. The researchers conclude that DHA supplementation during pregnancy has a beneficial effect on the infant’s problem-solving skills at 9 months of age.
Judge, MP, et al. Maternal consumption of a docosahexaenoic acid-containing functional food during pregnancy. American Journal of Clinical Nutrition, Vol. 85, 2007, pp. 1572-77
Maternal fish oil supplementation benefits children
PERTH, AUSTRALIA. Normal neuronal and visual development of infants depends on the availability of large amounts of docosahexaenoic acid (DHA) and arachidonic acid (ARA). Several studies have shown that maternal supplementation with relatively low doses of fish oils improves attention and mental processing in young children. There is also evidence that term infants fed on DHA-enriched formula develop better visual acuity.
Supplementing with fish oils (DHA) is known to cause a reduction in the availability of arachidonic acid and, since ARA is also required for brain development, there is some concern that supplementation with large doses of fish oil may reduce ARA availability to such an extent as to be detrimental.
Researchers at the University of Western Australia addressed this concern in a clinical trial involving 83 pregnant women. The women were randomized to receive placebo (olive oil) or fish oil (providing 1.1 gram/day of EPA and 2.2 grams/day of DHA) from 20 weeks’ gestation until birth. An analysis of phospholipid fatty acids from erythrocytes (red blood cells) in cord blood of newborns found that infants born to fish oil supplemented mother had a 225% higher EPA (eicosapentaenoic acid) content in their blood than did those born to control mothers. DHA content was 39% higher and ARA content 15% lower.
The effects on infants’ growth and brain development were evaluated at age 2.5 years. No significant differences were found in height, weight, and head circumference between children born to mothers who had supplemented with fish oil and those born to mothers in the placebo group. There was, however, a difference in eye and hand coordination between the two groups with children born to supplemented mothers performing significantly better when measured using the Griffiths Mental Development Scale. The researchers also noted a significantly higher level of EPA and DHA (and a lower level of ARA) in the cord blood of children with superior eye and hand coordination. The researchers conclude that maternal fish oil supplementation during pregnancy is safe for the fetus and infant, and may have potentially beneficial effects on the child’s eye and hand coordination.
Dunstan, JA, et al. Cognitive assessment of children at age 2½ years after maternal fish oil supplementation in pregnancy. Archives of Disease in Childhood. Fetal and Neonatal Edition. 2006 December 21 [Epub ahead of print]
Fish oil supplementation during pregnancy is safe
ADELAIDE, AUSTRALIA. There is still considerable controversy regarding the role of long chain omega- 3 polyunsaturated fatty acids (PUFAs) in infant development and little attention has been paid to the requirements of mothers for these nutrients. Two researchers at the University of Adelaide have just released a review of existing research findings concerning these subjects. One clinical trial found that women who supplemented with fish oil (1.5 grams eicosapentaenoic acid [EPA] and 1 gram docosahexaenoic acid [DHA] daily) from their 30th week of pregnancy extended the pregnancy by 4 days and gave birth to infants weighing an average of 100 grams more that infants born to mothers supplementing with placebos (olive oil). Other studies have failed to confirm these effects. A recent study found that DHA levels decrease rapidly in women after giving birth independent of whether they are breastfeeding or not. There is speculation that this relative DHA deficiency could be a major factor in postpartum depression, but clinical trials are needed to confirm this. The deficiency can be completely eliminated by supplementing with 200 to 400 mg/day of DHA. The evidence concerning the benefits of maternal DHA supplementation on infant development is inconclusive. One study found that infants with an adequate DHA status at 3 months of age scored better on a mental development test at age 1 year, but not at 2 years of age. The researchers conclude that there is no evidence that maternal DHA supplementation is harmful and that it may have subtle benefits to both mother and infant. However, further clinical trials are needed to verify this.
Makrides, Maria and Gibson, Robert A. Long-chain polyunsaturated fatty acid requirements during pregnancy and lactation. American Journal of Clinical Nutrition, Vol. 71 (suppl), 2000, pp. 307S- 11S
Fish consumption during pregnancy
BETHESDA, MARYLAND. In 2004 the U.S. government issued guidelines regarding fish consumption for pregnant women. The advice was to limit the consumption of seafood to 340 g per week, the objective being to limit the intake of neurotoxins that might adversely affect the fetus. But optimum fetal neurodevelopment depends on specific nutrients derived from dietary sources and the essential omega-3 fatty acid docosahexaenoic acid (DHA) is not only one of the most critical, but seafood is the major source. A study has just appeared in the journal Lancet, which examines an important question, i.e. is the limitation of seafood intake to less than 340 g/week during pregnancy potentially detrimental to fetal neurodevelopment? In this study, Hibbein et al report on the results of follow-up study based in Bristol, UK. Over 14,500 pregnancies were involved and 13,988 children survived for at least 12 months. Questionnaires were used during pregnancy and the children were followed for 6 months to 8 years. The object was to assess developmental, behavioral and cognitive outcomes as they related to the level of seafood consumption during pregnancy. About 85% of the eligible expectant mothers participated. Questionnaires were used periodically to determine development and behavioral characteristics; the intelligence quotient (IQ) at age 8 was determined for 5449 children.
After adjustments for confounding, maternal seafood intake during pregnancy of less that 340 g/week was associated with increased risk of the children in question being in the lowest fifth for verbal IQ and in addition there was a significant trend to greater risk as the seafood consumption declined to zero. Low maternal seafood intake was also associated with increased risk of suboptimal outcomes for development in the areas of social behavior, as well as motor, communication and social development, and for each outcome the lower the fish intake the higher the risk for suboptimal development. The authors conclude that maternal seafood consumption of less than 340 g/week did not protect children from adverse neural development, and that in fact intake exceeding 340 g/week (12 oz or 3/4 lb) resulted in beneficial effects on child development. Thus the authors conclude that following the guidelines could actually be detrimental, and that the results suggest that the benefits from eating more than 340 g of seafood per week outweighed the risk of harm from exposure to trace contaminants.
Hibbein, J. R. et al. Maternal Seafood Consumption in Pregnancy and Neurodevelopmental Outcomes in Childhood (ALSPAS study): An Observational Cohort Study. Lancet, 2007, Vol. 369, Feb 17, pp. 579-84.
Fish oils improve IQ in children
OSLO, NORWAY. The human brain develops rapidly during the last trimester (13 weeks) of pregnancy and the first months following birth. This brain growth depends on an adequate supply of docosahexaenoic acid (DHA) and arachidonic acid. Norwegian researchers recently completed a study of the effect of maternal fish oil supplementation on IQ (intelligence quotient) in the child at 4 years of age.
A total of 341 pregnant women took part in the study. They were randomized to receive 2 teaspoons (10 ml) per day of cod liver oil or the same amount of corn oil from the 18th week of pregnancy to 3 months after delivery. To be accepted into the study, the women also had to declare their intention of breastfeeding their infant. The fish oil (cod liver oil) provided 1200 mg/day of DHA (docosahexaenoic acid) and 800 mg/day of EPA (eicosapentaenoic acid). The breast milk of mothers receiving the fish oil supplement contained almost 3 times as much DHA as did the breast milk of mothers receiving corn oil.
At 4 years of age, 84 children had their IQ tested using the Kaufman Assessment Battery for Children (K-ABC). The children whose mothers had supplemented with fish oil and who had been breastfeed for at least 3 months after birth scored an average of 4 points higher on the K-ABC scale. The researchers point out that this increase is highly significant in overall terms and would be difficult to attain through normal teaching procedures.
Helland, Ingrid B., 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, Vol. 111, January 2003, pp. 39-44
Fish consumption and pregnancy outcome
COPENHAGEN, DENMARK. Danish researchers report that women who consume fish or seafood once a week during the first 16 weeks of pregnancy have a 3.6 times lower risk of giving birth to a low birth weight (less than 2500 grams) or premature (born before 259 days) baby than do women who never consume fish or seafood. The study involved almost 9000 women who completed a food frequency questionnaire. The researchers found that women whose daily intake of fish was less than 15 grams, corresponding to a fish oil intake of 150 mg/day, were significantly more likely to give birth to a preterm or underweight baby than were women with higher intakes. They suggest that small amounts of fish oil may confer protection against preterm delivery and low birth weight.
Olsen, Sjurour Frooi and Secher, Niels Jorgen. Low consumption of seafood in early pregnancy as a risk factor for preterm delivery: prospective cohort study. British Medical Journal, Vol. 324, February 23, 2002, pp. 1-5
Mothers’ fish oil supplementation benefits infants
PORTLAND, OREGON. Animal experiments have shown that monkeys born by mothers with low blood levels of docosahexaenoic acid (DHA) develop impaired vision. There is also evidence that premature human infants fed standard infant formulas (very low in DHA) have impaired visual function which can be improved significantly by adding fish oils to their formulas. All this adds to the growing evidence that DHA is essential for the proper development of the brain and retina in the fetus and infant.
Researchers at the Oregon Health Sciences University recently set out to answer the question “Do high intakes of DHA by pregnant women increase the DHA level in their newborn infants?” Their clinical trial involved 31 healthy, pregnant women 15 of whom were assigned to receive 2.6 grams/day of omega-3 fatty acid from fish (1.01 grams DHA/day) from their 26th to their 35th week of pregnancy. The remaining women served as controls. The fish oil supplement was taken as a combination of tinned sardines and fish oil capsules; either 1 half tin of sardines plus 7 fish oil capsules per day, 1 tin of sardines (3 3/4 oz) plus 3 fish oil capsules per day or 10 fish oil capsules (10 grams) per day. Blood samples were collected from mothers at entry to the study, monthly after entry and at delivery, and from the infants at delivery. The level of DHA in the red blood cells of supplemented mothers rose from 4.69% (of total fatty acids) at entry to 7.15% at the end of week 34 and then declined (as expected) to 5.97% at delivery. DHA increases in the blood plasma paralleled the increase in the red blood cells, but at a lower level. DHA levels in newborn infants differed greatly depending on whether the mothers had supplemented or not. Red blood cell levels in infants born by supplementing mothers were 35.2% higher than in the control infants and blood plasma levels were 45.5% higher (5.05% vs. 3.47%).
The researchers believe that supplementing pregnant mothers with fish oil may benefit brain and retinal development in their offspring particularly if born prematurely. They point out that supplementing from mid-pregnancy to the 34th week is perfectly safe and may reduce the incidence of preeclampsia (pregnancy-related high blood pressure) as well.
Connor, William E., et al. Increased docosahexaenoic acid levels in human newborn infants by administration of sardines and fish oil during pregnancy. Lipids, Vol. 31 (suppl), 1996, pp. S183- S87
Pilot trial of fish oil for post-partum depression
TUCSON, ARIZONA. Post-partum depression (PPD) affects about 10-15% of mothers in the USA, usually within the first month following delivery. Children of affected mothers may experience impaired attachment and PPD may adversely affect their behavioral and cognitive development. Several studies have shown that mothers with PPD tend to be deficient in long-chain omega-3 fatty acids, specifically EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Other studies have found that women with an adequate intake of DHA (from seafood or supplements) tend to be less likely to develop PPD. Based on these observations researchers at the University of Arizona Medical School decided to evaluate if fish oil supplementation would diminish depression in women diagnosed with PPD.
Their 8-week pilot study involved 16 women with PPD. The extent of depression was evaluated using the Edinburgh Postnatal Depression Scale (EPDS) and the Hamilton Rating Scale for Depression (HRSD). The EPDS scores ranged from 15.3 to 19.0 at the start of the study (a score equal to or greater than 9.0 indicates depression). The HRSD scores ranged from 18 to 20.3 with a score equal to or greater than 15 signifying depression.
The study participants were randomized to receive placebo capsules (corn oil + 1% fish oil) or 0.5, 1.4 or 2.8 grams/day of a fish oil having an EPA:DHA ratio of 1.5:1 (EPAX 5500, Pronova, Lysker, Norway) for 8 weeks. The participants were followed up and checked for depression scores at weeks 1, 2, 4, 6, and 8. At week 8 the average EPDS score had decreased to 9.3 (a 51.5% reduction) and the HRSD score had fallen by 48.8% to an average of 10 in the fish oil groups. Improvement was most noticeable in the group receiving 1.4 grams/day of EPA + DHA and no advantage was seen by taking 2.8 grams/day. However, just 0.5 gram/day also was successful in reducing both EPDS scores and HRSD scores to normal (non-depressed) levels. The researchers conclude that fish oil supplementation in women with PPD is well tolerated and effective in reducing symptoms of depression.
Freeman, MP, et al. Randomized dose-ranging pilot trial of omega-3 fatty acids for postpartum depression. Acta Psychiatrica Scandinavica, Vol. 113, January 2006, pp. 31-35
Fatty acid status and post-partum depression
MAASTRICHT, THE NETHERLANDS. There is substantial evidence that major depression is associated with changes in the fatty acid composition of serum lipids. Researchers have noted that the ratio of omega-6 fatty acids (linoleic acid, arachidonic acid) to omega-3 fatty acids (linolenic acid, eicosapentaenoic acid, docosahexaenoic acid) is substantially higher in depressed patients than in normal controls. There is also evidence that omega-3 fatty acid levels and, more specifically, DHA (docosahexaenoic acid) levels are substantially lower in depressed patients. Researchers at Maastricht University have now extended these findings to include post-partum depression (PPD).
Their study included 48 healthy, pregnant women who had blood samples taken shortly after delivery. These blood samples were analyzed to determine the fatty acid profile in serum phospholipids (PL) and cholesteryl esters (CE). The women were also interviewed within 6 to 10 months after delivery to ascertain whether they suffered from PPD. Ten of the women (21%) had indeed developed PPD with most reporting depressive symptoms immediately following delivery. Analyses of the blood samples showed that DHA concentration and total omega-3 level were significantly lower in both the PL and CE fractions of blood serum taken from women who developed PPD.
The Dutch researchers speculate that the milder form of PPD, post-partum blues, also is related to a fatty acid imbalance and is currently investigating this in a separate study involving 98 women. They conclude that pregnant women at risk for developing PPD may benefit from preventive supplementation with DHA, perhaps in combination with its precursor docosapentaenoic acid.
De Vriese, SR, et al. Lowered serum n-3 polyunsaturated fatty acid (PUFA) levels predict the occurrence of postpartum depression: further evidence that lowered n-PUFAs are related to major depression. Life Sciences, Vol. 73, 2003, pp. 3181-87
Post-partum depression and functional DHA status
MAASTRICHT, THE NETHERLANDS. About 20% of Dutch women develop post-partum depression shortly after giving birth with the peak incidence reached about 32 weeks post-partum. There is growing evidence of an association between low blood levels of docosahexaenoic acid (DHA), a major component of fish oil, and post-partum depression (PPD). Dutch researchers report that it may not be DHA level per se that is the important factor, but rather the increase in DHA availability, or DHA functional status following birth. Availability is expressed as the ratio of DHA to DPA (docosapentaenoic acid). DPA is the intermediary step in the conversion of EPA (eicosapentaenoic acid) to DHA. DHA availability is reduced during pregnancy and normalizes following delivery; however, it this normalization is slow depression may result.
The Dutch study involved 112 pregnant women who had blood samples collected at week 36 of pregnancy, immediately following delivery, and 32 weeks post-partum. At week 32 post-delivery the women were assessed for the presence of PPD using the Edinburgh Postnatal Depression Scale (EPDS) questionnaire. Twenty-four of the women (21%) were found to suffer from depression (EPDS score equal to or greater than 10). Seventy-five percent of the depressed women rated themselves as “not healthy” in the months following delivery as compared to only 6% in the non-depressed group (EPDS score less than 10).
The researchers did not observe any statistically significant relationship between post-partum depression and DHA level as such; however, they did find a significant correlation between PPD and the increase in DHA:DPA ratio between delivery and 32 weeks post-partum. Women with a slower increase in this ratio had a 10% higher risk of PPD. There was no indication that breast-feeding increased the risk of PPD. The researchers recommend further studies, but suggest that women who have recently given birth increase their intake of DHA.
Otto, SJ, et al. Increased risk of postpartum depressive symptoms is associated with slower normalization after pregnancy of the functional docosahexaenoic acid status. Prostaglandins, Leukotrienes and Essential Fatty Acids, Vol. 69, 2003, pp. 237-43
Post-partum depression linked to DHA deficiency
ROCKVILLE, MARYLAND. Mothers selectively transfer docosahexaenoic acid (DHA) to their fetus during pregnancy to support optimal neurological development. If the dietary intake of DHA is insufficient to meet the needs of both mother and fetus, then the needs of the fetus are met first. This may result in the mother becoming deficient and the subsequent development of major depression and other affective disorders. Dr. Joseph Hibbeln of the US National Institutes of Health report that the incidence of post-partum depression (PPD) is clearly linked to DHA status and seafood consumption.
Dr. Hibbeln evaluated the results of 41 relevant studies involving over 14,000 women located in 23 different countries. He compared the incidence of post-partum depression in new mothers in each country with the average seafood consumption and average DHA concentration in the mothers’ milk in the country. The results were remarkable. Dr. Hibbeln found a clear correlation between the incidence of PPD and seafood consumption. The highest incidence of PPD (24.5%) was found in South Africa, which also reported the lowest seafood intake at 8.6 lb/person/year. In comparison, Japan reported a PPD incidence of only 2% and an average seafood consumption of 147.7 lb/person/year. In the United States average seafood intake amounted to 48.1 lb/person/year with a corresponding PPD incidence of 11.5%. Numbers for Canada were similar at 50.7 lb/person/year seafood consumption and 12.7% PPD.
Analyses of fatty acid content of mothers’ milk were available for 16 countries. While there was no correlation between PPD and the content of arachidonic acid and eicosapentaenoic acid, there was a clear correlation between PPD and low DHA level. South Africa reported the lowest DHA content (0.15% of total fats in mothers’ milk) and the highest PPD incidence at 24.5%. The average DHA level in mothers’ milk in Japan was 0.81% versus a PPD incidence of 2%. Average DHA level in the USA was 0.17% (PPD incidence of 11.5%).
Although there are clearly other factors predisposing to post-partum depression, Dr. Hibbeln found that the effects of low socioeconomic status, young maternal age, no partner, and poor education were minor when compared to the effect of seafood consumption and low DHA status. He points out that numerous studies have shown that DHA status can be safely and effectively improved by supplementation with fish oil. Specifically, studies have found that supplementation with 1.1 gram/day of DHA will increase breast milk concentration to 0.8% without any adverse effects. A level of 0.8% is equivalent to the average level observed in Japan and is associated with a low 2.0% risk of PPD.
Hibbeln, J. Seafood consumption, the DHA content of mothers’ milk and prevalence rates of postpartum depression: a cross-national, ecological analysis. Journal of Affective Disorders, Vol. 69, 2002, pp. 15-29
Conclusion: Supplementation with DHA appears necessary for optimal development of the brain and eyes of formula-fed infants.
Conclusion: There was no improvement in growth or visual function in healthy term infants feed formula supplemented with DHA for 12 months.
Conclusion: DHA-supplemented formula increases information processing speed in preterm infants.
Conclusion: Preterm babies fed DHA-enriched formula had more rapid information processing.
Conclusion: Breast-fed infants have higher DHA levels in their cortex than do formula-fed infants.
Conclusion: Fish oil-fortified formula improves visual acuity in preterm infants.
Conclusion: Fish oil-fortified formula improves visual and cortical function in preterm infants.
Conclusion: Formula for preterm infants should be supplemented with omega-3 fatty acids including fish oils.
Conclusion: Fish oil-fortified formula improves visual acuity in preterm infants.