Little information exists on how perception of the food (or “energetic”) environment affects body composition and reproductive investment. Therefore, Dr. Tonia S. Schwartz, a James S. McDonnell post-doctoral fellow in the office of energetics, and Dr. David B. Allison, distinguished professor and director of the Nutrition Obesity Research Center and office of energetics, at the University of Alabama at Birmingham, tested the hypothesis that female mice — who are themselves consuming standard chow diets but are exposed to conspecifics eating a rich “cafeteria diet,” which allows for free access to junk foods — will exhibit altered weight gain and reproductive investment. Co-investigators in the study are Ms. Renee Gainer, animal behaviorist/environmental enrichment coordinator, and Dr. Erik D. Dohm, senior clinical veterinarian, at UAB’s Animal Resources Program; Dr. Maria S. Johnson, research associate in the department of nutrition sciences; and Dr. J. Michael Wyss, professor in the department of cell, developmental, and integrative biology.
Female C57BL/6 mice, commonly used in laboratories, were raised on a cafeteria diet. At maturity, the subjects were switched to a standard chow diet, and their cage-mates were assigned to consume either a cafeteria diet (treatment, n = 20) or standard chow (control, n = 20). Subjects were mated and the pups were raised to weaning; subjects and pups were then analyzed for body composition.
The researchers found that treatment (cage-mate consuming a “cafeteria diet” had no discernable effect on dam body weight or composition, but it caused her pups to have lower body weight (P = 0.036) and less fat mass (P = 0.041). Additionally, the treatment had a nearly significant effect on failed first pregnancies, (14/19 versus 8/19, P = 0.099). They concluded that these data indicate that perceived food environment (independent of the diet actually consumed) can produce small pups with less body fat as well as possibly induce difficulties in pregnancy for dams. The team recommends that replication and mechanistic studies should follow.
“Second-Hand Eating? Maternal Perception of the Food Environment Affects Reproductive Investment in Mice” was published in April in the journal Obesity.