(1109) Proinflammatory Omega-6 and Arachidonic Acid are Increased in Breast Milk of Mothers with Overweight/Obesity

Friday, January 31, 2025

4:00 PM – 6:00 PM

Submitting Author and Presenting Author(s)

Michael G. Ross, MD, MPH

Distinguished Professor
The Lundquist Institute at Harbor-UCLA Medical Center
Torrance, California, United States

Coauthor(s)

MC

MacKenzie Cervantes, MS

The Lundquist Institute at Harbor-UCLA Medical Center
Torrance, California, United States
GH

Guang Han, MD

The Lundquist Institute at Harbor-UCLA Medical Center
Torrance, California, United States
LB

Lihiri Bora, MD

The Lundquist Institute at Harbor-UCLA Medical Center
Torrance, California, United States
Mina Desai, MSc, PhD

Associate Professor
The Lundquist Institute at Harbor-UCLA Medical Center
Torrance, CA, United States

Objective: Human milk composition varies depending on maternal diet, duration of nursing, time of day and maternal body habitus. Among the critical milk components, essential polyunsaturated fatty acids (PUFA omega-6 and omega-3) must be supplied to the newborn for brain growth and development. Western diets have led to an increase in maternal consumption of omega-6 linoleic acid (LA) and a decrease in omega-3 α-linolenic acid (ALA) PUFA. Through the elongation and desaturation process, LA is converted to arachidonic acid (AA) and ALA to docosahexaenoic acid (DHA). While AA and DHA are important for brain development, an excessive amount of total omega-6 (ω6), AA and a higher AA/DHA ratio are associated with accelerated weight gain in infants, increased oxidative stress, inflammation and cognitive impairment. As women with OW/OB have increased total milk fat content, we sought to determine the influence of maternal body mass index (BMI) on specific PUFA levels.

Study Design: We studied women who delivered singleton, term neonates and were exclusive breastfeeding at 7-9 weeks postpartum. Among both normal weight (BMI 18.5-24.9 kg/m²) and women with overweight and obesity (OW/OB; BMI≥25 kg/m²), continuous milk samples (10ml) from foremilk to hindmilk were obtained via pump until the breast was emptied. First and last pumped milk samples were analyzed. Milk and maternal plasma lipidomics were undertaken (Lipidyzer Platform).

Results: In women with OW/OB, breast milk total ω6, LA and AA levels were significantly increased in both the first (foremilk) and last (hindmilk) samples as compared to normal weight (Fig 1). Importantly, the AA/DHA ratio was significantly increased in foremilk and hindmilk of women with OW/OB (Fig 2).

Conclusion: The increased ω6, LA and AA levels including an increased AA/DHA ratio in the breast milk of women with OW/OB has a potential risk for infant obesity, inflammation and adverse cognitive/behavioral outcomes. Novel strategies to optimize milk AA/DHA are urgently needed during pregnancy and lactation, particularly in women with obesity.