Interesterified fat or palm oil as substitutes for partially hydrogenated fat in maternal diet can predispose obesity in adult male offspring.

BACKGROUND & AIMS: Palm oil (PO) and interesterified fat (IF) have been used to replace partially hydrogenated fat (PHF), which is rich in trans isomers, in processed foods. The purpose of this study was to investigate whether normolipidic diets containing PHF, IF, or PO consumed during pregnancy and lactation affect total body adiposity and adipose tissue morphology of adult offspring mice.

METHODS

Four groups of female C57BL/6 mice were fed, during pregnancy and lactation, a control diet (control group, CG), a PHF diet (trans group, TG), a PO diet (PG group), or an IF diet (IG group). After weaning (at 21 days), male pups received the control diet for 70 days. Food intake and body weight were monitored in all groups throughout the experimental period. At 3 months of age, mice were sacrificed and the inguinal (IWAT), epididymal (EWAT), retroperitoneal (RPWAT), and mesenteric (MWAT) adipose fat pads were removed and weighed. Adiposity was quantified by micro computed tomography (micro-CT), and adipocyte areas and cell number were analyzed by histology.

RESULTS

PG and IG offspring gained more weight than CG and TG groups (p < 0.01) during the first 10 weeks after weaning, resulting in higher final body weights (p < 0.05). IG mice and PG mice had respectively heavier EWAT and IWAT than TG and CG mice. Micro-CT scanning revealed that the total volumes of internal, external, and total fat depots were greater in IG animals, as compared to the other groups. Larger adipocyte areas were observed in EWAT and IWAT in IG and TG, respectively, in comparison to CG and PG mice. PG mice showed increased adipocyte numbers in IWAT.

CONCLUSIONS

Maternal intake of IF and/or PO during pregnancy and lactation predisposes the offspring to the development of obesity in adult life in mice.