BF: Dietary Factors, Breast Milk and Infant Outcomes (2008)


Helland IB, Saugstad OD, Saarem K, Van Houwelingen AC, Nylander G, Drevon CA. Supplementation of n-3 fatty acids during pregnancy and lactation reduces maternal plasma lipid levels and provides DHA to the infants. J of Maternal-Fetal and Neonatal Medicine. July 2006; 19 (7): 397-406.

PubMed ID: 16923694
Study Design:
Randomized Controlled Trial
A - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:

To examine the effect of maternal supplementation with very long chain PUFAs on the fatty acid patterns in maternal and infant plasma and umbilical tissue, along with maternal and infant concentrations of TAGs and cholesterol.

Inclusion Criteria:
  • Healthy women with singleton pregnancy
  • 19 years to 35 years of age
  • Nulli- or primiparous
  • Intend to breastfeed their infants' no supplementation of n-3 fatty acids during pregnancy.
Exclusion Criteria:

Premature births, birth asphyxia, infections and anomalies in infants that required special attention.

Description of Study Protocol:
  • Recruitment: Not reported. Enrollment at first routine ultrasound scan exam at week 17 to 19 of pregnancy.
  • Design: Double-blind, randomized controlled supplementation trial
  • Intervention: Random assignment to receive either 10ml per day cod liver oil or 10ml per day corn oil (Petter Möller, Avd Orkla ASA, Oslo, Norway) or corn oil. Women consumed supplements until three months after delivery.
  • Statistical analysis:  Two-tailed student's T-test to examine differences between supplementation groups for continuous variables; Chi-square test used for categorical variables. P<0.05 as significant.
Data Collection Summary:

Timing of Measurements

  • Week 18 of pregnancy: Subject enrollment, begin supplementation, blood sample taken; FFQ
  • Week 35 of pregnancy: Blood sample taken; FFQ
  • Upon delivery: Blood sample taken from umbilical cord
  • Four weeks and 13 weeks post-delivery: Blood sample taken from infants; milk samples collected from morning feed
  • Three months post delivery: Infant diet questionnaire.

Dependent Variables

  • Plasma and breast milk FA (GLC)
  • FA composition of phospholipids (umbilical and venous, total lipid extraction, GLC)
  • ALAT, gamma GT, creatinine, TAGs, cholesterol, HDL-cholesterol (clinical chemistry).

Independent Variables

Supplementation with cod liver oil or corn oil.

Control Variables

Timing of measurements, RCT.

Description of Actual Data Sample:

Initial N

N=175 in cod liver oil and N=166 in corn oil groups.

Attrition (final N)

  • 160 in the cod liver group at week 35
  • 154 in the corn oil group at week 35
  • 137 in the cod liver group at three months postpartum
  • 121 in the corn oil group at three months postpartum.

Other relevant demographics

No differences in baseline maternal or infant birth characteristics between groups.


Oslo, Norway.

Summary of Results:

At 35 weeks of pregnancy, there was a higher concentration of TAGs and a lower concentration of HDL-cholesterol in the corn oil group than in the cod liver oil group. 

Variables Cod Live Oil (N=160) Corn Oil (N=154) Statistical Significance of Group Difference
TAGS 2.7±1.0 3.1±0.9 P<0.001 (time, oil, time *oil)
Cholesterol 7.1±1.3 7.4±1.3 P<0.001 (time only)
HDL-cholesterol 1.9±0.4 1.7±0.4 P<0.001 time and time *oil P<0.01 oil

Concentration of n-3 very long chain PUFAs and the ration of n-3 to n-6 in umbilical plasma phospholipids were higher in cod liver oil compared to corn oil group. Significant differences between arteries and veins were found for all reported FAs, except EPA and DHA

Concentrations of n-3 VLC PUFAs were higher in breast milk and in infant plasma phospholipids from cod liver oil group, whereas n-6 was higher in corn oil group. 


Author Conclusion:

Compared to supplementation with corn oil (n-6 long-chain PUFAs), maternal supplementation with cod liver oil (n-3 very long chain PUFAs) increases the supply of DHA to the fetus and newborn infant. Maternal plasma TAGs decrease and HDL-cholesterol increases.

Funding Source:
Peter Moller, Avd Orkla ASA, Aktieselskabet Freia Chocoladefabriks Medicinske Fond
Food Company:
University/Hospital: Throne Holst Fond for Ernaeringsforskning
Foundation associated with industry:
Reviewer Comments:

Refer to Helland et al, 2001 for trial specifics. This particular publication focused on the effect of the supplementation on maternal and infant FA patterns and on TAGs and cholesterol.

Quality Criteria Checklist: Primary Research
Relevance Questions
  1. Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies) Yes
  2. Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about? Yes
  3. Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice? Yes
  4. Is the intervention or procedure feasible? (NA for some epidemiological studies) Yes
Validity Questions
1. Was the research question clearly stated? Yes
  1.1. Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified? Yes
  1.2. Was (were) the outcome(s) [dependent variable(s)] clearly indicated? Yes
  1.3. Were the target population and setting specified? Yes
2. Was the selection of study subjects/patients free from bias? Yes
  2.1. Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study? Yes
  2.2. Were criteria applied equally to all study groups? Yes
  2.3. Were health, demographics, and other characteristics of subjects described? Yes
  2.4. Were the subjects/patients a representative sample of the relevant population? Yes
3. Were study groups comparable? Yes
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) Yes
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? Yes
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) Yes
  3.4. If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis? N/A
  3.5. If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.) N/A
  3.6. If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")? N/A
4. Was method of handling withdrawals described? Yes
  4.1. Were follow-up methods described and the same for all groups? Yes
  4.2. Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.) Yes
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? Yes
  4.4. Were reasons for withdrawals similar across groups? N/A
  4.5. If diagnostic test, was decision to perform reference test not dependent on results of test under study? N/A
5. Was blinding used to prevent introduction of bias? Yes
  5.1. In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? Yes
  5.2. Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.) Yes
  5.3. In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded? N/A
  5.4. In case control study, was case definition explicit and case ascertainment not influenced by exposure status? N/A
  5.5. In diagnostic study, were test results blinded to patient history and other test results? N/A
6. Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described? Yes
  6.1. In RCT or other intervention trial, were protocols described for all regimens studied? Yes
  6.2. In observational study, were interventions, study settings, and clinicians/provider described? N/A
  6.3. Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect? Yes
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured? Yes
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? N/A
  6.6. Were extra or unplanned treatments described? N/A
  6.7. Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups? Yes
  6.8. In diagnostic study, were details of test administration and replication sufficient? Yes
7. Were outcomes clearly defined and the measurements valid and reliable? Yes
  7.1. Were primary and secondary endpoints described and relevant to the question? Yes
  7.2. Were nutrition measures appropriate to question and outcomes of concern? Yes
  7.3. Was the period of follow-up long enough for important outcome(s) to occur? Yes
  7.4. Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures? Yes
  7.5. Was the measurement of effect at an appropriate level of precision? Yes
  7.6. Were other factors accounted for (measured) that could affect outcomes? Yes
  7.7. Were the measurements conducted consistently across groups? Yes
8. Was the statistical analysis appropriate for the study design and type of outcome indicators? Yes
  8.1. Were statistical analyses adequately described and the results reported appropriately? Yes
  8.2. Were correct statistical tests used and assumptions of test not violated? Yes
  8.3. Were statistics reported with levels of significance and/or confidence intervals? Yes
  8.4. Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)? N/A
  8.5. Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? Yes
  8.6. Was clinical significance as well as statistical significance reported? N/A
  8.7. If negative findings, was a power calculation reported to address type 2 error? N/A
9. Are conclusions supported by results with biases and limitations taken into consideration? Yes
  9.1. Is there a discussion of findings? Yes
  9.2. Are biases and study limitations identified and discussed? Yes
10. Is bias due to study's funding or sponsorship unlikely? Yes
  10.1. Were sources of funding and investigators' affiliations described? Yes
  10.2. Was the study free from apparent conflict of interest? Yes