Karen Harris

Karen Harris is a professional writer and editor with more than two decades of experience in research-driven nonfiction writing. With a background in journalism and a Master's degree in English, she brings a meticulous approach to fact-finding, source evaluation, and clear communication of complex topics. Her work spans health, lifestyle, and consumer education, always with a focus on accuracy and readability.

Context

Palmitic acid (PA) is the dominant saturated fatty acid in human milk, where 60–80% is esterified at the SN-2 position of triglycerides. This structural position makes PA readily absorbable: intestinal lipase cleaves at the SN-1 and SN-3 positions, leaving PA in a water-soluble monoglyceride form. Palm oil - widely used in infant formula to match human milk palmitic acid levels - carries PA predominantly at the SN-1,3 positions instead. When SN-1,3-bound PA is released as a free fatty acid, it binds calcium in the gut to form insoluble calcium-palmitate soaps, which are excreted in stool, potentially reducing calcium and fat absorption and increasing stool hardness. Some formulas now replace palm oil partly or fully with a SN-2-enriched fat blend (beta-palmitate, e.g. Betapol, INFAT) to more closely mimic human milk triglyceride structure. This ESPGHAN Committee on Nutrition position paper systematically reviewed the available clinical evidence on health effects of both palm oil and SN-2-palmitate in infant formula.

Study Overview

Design: Systematic review of RCTs and large observational studies + expert consensus position paper (ESPGHAN Committee on Nutrition)


Database searched: PubMed/Medline and Cochrane Database of Systematic Reviews (up to November 2017)


Studies included: 12 studies on palm oil/palm olein (PO/POL); 21 studies on SN-2-palmitate


Population: Healthy term infants (majority); some studies included preterm infants


Funding: ESPGHAN (professional society); the majority of included studies were industry-funded or conducted by formula company employees. Multiple committee members report conflicts of interest with Nestlé, Nutricia, Danone, Abbott, and others


Evidence Certainty (GRADE): Not formally GRADE-rated; described as variable quality, inconsistent, and insufficient for definitive conclusions across most outcomes


Outcomes reviewed: Stool composition and consistency, infantile colic, bone health and growth, lipid metabolism, fecal microbiota, and long-term disease markers.

Key Findings

Palm Oil / Palm Olein (PO/POL) - 12 studies:

  • Fat and calcium absorption: All 5 relevant RCTs consistently found lower fat and calcium absorption in infants fed PO/POL-based formula compared to PO-free formula. Lower LC-PUFA absorption also reported in one study.
  • Stool consistency: Two studies (one large observational, one RCT) reported less frequent stools and harder stool consistency in infants fed POL-containing formula. A meta-analysis of RCTs confirmed significantly harder stools in POL-predominant versus POL-free formulas (p < 0.001), though stool frequency was not different.
  • Bone health: Two of three RCTs found lower bone mineral content (BMC) in infants fed PO/POL formula versus PO-free formula. One retrospective study at 4 years of age found no significant differences in BMC or BMD between feeding groups. A systematic review concluded consistently lower calcium and fat absorption and lower BMC in PO-fed infants.
  • Growth: All three bone health RCTs reported no difference in anthropometric measurements between PO/POL and PO-free groups.
  • Lipid metabolism: Two RCTs; mixed and inconclusive results.
  • Infantile colic: No relevant studies identified.
  • Process contaminants: Palm oil contains glycerol-based process contaminants (glycidyl esters, 3-MCPD), which EFSA has flagged as a potential genotoxic/carcinogenic concern - particularly for exclusively formula-fed infants, whose exposure slightly exceeds the stipulated tolerable daily intake. Industry mitigation strategies have substantially reduced levels in recent years.

SN-2-Palmitate / Beta-Palmitate - 21 studies:

  • Fat and calcium absorption: 7 of 8 RCTs consistently showed improved calcium and fat absorption with higher SN-2-palmitate content. One congress abstract showed no effect.
  • Stool consistency: Three RCTs showed a trend toward softer stools with SN-2-palmitate formula; effects were enhanced when prebiotic oligosaccharides were added. Notably, some mothers reported concern about runny stools in the SN-2 group.
  • Infantile colic: Two RCTs and one large uncontrolled observational study showed reduction in crying episodes/colic frequency. However, most studies used multiple simultaneous interventions (hydrolyzed protein, prebiotics), making it difficult to attribute effects specifically to SN-2-palmitate.
  • Bone health: Two RCTs showed short-term positive effects on bone mineral content at 12 weeks. However, an open-label follow-up of part of one cohort at 10 years of age showed no persistent long-term effect. Clinical significance is uncertain as breastfed infants have BMC values below both formula groups yet are considered the reference standard.
  • Growth: No difference in anthropometric outcomes between SN-2-palmitate and control formula in any study.
  • Fecal microbiota: One study found higher Lactobacillus and Bifidobacterium counts in the high SN-2-palmitate group. Evidence otherwise very limited.
  • Lipid metabolism: Two studies; results are preliminary and no clinically meaningful conclusions possible.
  • Long-term disease markers (CVD, T2DM, obesity, cancer): No studies published.

Limitations

  • The majority of included studies were industry-funded or conducted by formula company employees, introducing substantial risk of bias across the evidence base.
  • Studies have highly variable methodology, differing intervention formulas, population characteristics, and outcome measures, making direct comparison difficult.
  • Many studies tested multiple simultaneous formula modifications (SN-2-palmitate combined with prebiotics, hydrolyzed protein, altered mineral content), making it impossible to isolate the effect of fat positioning alone.
  • Several studies were underpowered for their primary outcomes.
  • No studies examined long-term health outcomes (cardiovascular disease, obesity, diabetes, cancer).
  • Evidence base for colic, microbiota, and lipid metabolism outcomes remains very sparse.
  • Literature search cutoff was November 2017; studies published since are not included.
  • EFSA rejected two health claim petitions for beta-palmitate in 2011 and 2014 based on insufficient evidence.

Neutral Interpretation

This ESPGHAN position paper provides a thorough overview of an area where the underlying biochemistry is well understood but the clinical evidence remains limited and methodologically heterogeneous. Palm oil use in formula is associated with harder stools and short-term reductions in calcium and fat absorption - effects with a clear mechanistic explanation - but these do not appear to translate into significant growth differences or confirmed long-term harm. SN-2-palmitate formulas improve fat and calcium absorption and may soften stools, but cannot be considered clinically essential based on current evidence. Notably, even high-SN-2 formulas remain below breastfed infants in several parameters, and no long-term outcome data exist for either intervention. The pervasive industry funding of included studies warrants caution in interpreting the full body of evidence.

ESPGHAN Recommendations (verbatim conclusions)

  1. Inclusion of high SN-2-palmitate fat blend in infant formulas may have short-term effects on stool consistency but cannot be considered essential.
  2. There is insufficient evidence to suggest that palm oil should be avoided as a source of fat in infant formulas for health reasons.
  3. All formula producers should take measures to minimize glycerol-based process contaminants (glycidyl esters, 3-MCPD) in infant formulas.

Full Citation

Bronsky J, Campoy C, Embleton N, et al.; ESPGHAN Committee on Nutrition. Palm Oil and Beta-palmitate in Infant Formula: A Position Paper by the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) Committee on Nutrition. J Pediatr Gastroenterol Nutr. 2019;68(5):742–760. 

PMID: 31022096. 

Available at: https://pubmed.ncbi.nlm.nih.gov/31022096/

Disclosure

This summary is based on the published full-text position paper. It is provided for informational purposes only and does not constitute medical advice.