February 19, 2020

Interpretive Summary: High and low protein diets during gestation in the rat

Interpretive Summary: Effect of low- and high-protein maternal diets during gestation on reproductive outcomes in the rat: a systematic review and meta-analysis

By: Anne Wallace

Health problems like metabolic syndrome, cardiovascular disease and obesity may develop in offspring whose gestational period involved poor maternal nutrition. This phenomenon includes both over- and under-nutrition and is consistently observed across multiple types of animals, including humans. However, the effects of maternal over- or under-nutrition with dietary proteins (but not other nutrients) on the health of their offspring are not well studied. 

In this study published in the Journal of Animal Science (January 2020 issue), researchers conducted a systematic review and meta-analysis to investigate how protein modification of maternal diets during the gestational period impacted gestational feed intake, gestational weight gain, litter size, and litter weight, in rats.

Thirty-two randomized studies between 1972 and 2019 were identified that met the authors’ strict criteria. Both high- and low-protein diets were found to produce detrimental effects. Low-protein diets reduced gestational weight gain, feed intake, and litter weight, but had no effect on litter size. High-protein diets reduced gestational feed intake but had no effect on litter size or weight (maternal or offspring).

Overall, the results of this study suggest that a low-protein diet during the gestational period is detrimental to offspring litter weights, in rats. The effect of high protein diets reduced gestational feed intake, with unknown impacts. More studies looking at how an excess or lack of other macronutrients during the gestational period may have on the health of offspring may be warranted.