Is dietary macronutrient composition during pregnancy associated with offspring birth weight? An observational study - Volume 119 Issue 3
From Lily Nichols RDN on Facebook:
Research: Is dietary macronutrient composition during #pregnancy associated w/ offspring birth weight?
The results of this observational study mirror exactly what I've observed in clinical practice for years and continue to hear from people who follow my real food approach to pregnancy and gestational diabetes.
In short, higher carbohydrate intake was associated with higher birth weight while higher fat intake was associated with lower birthweight. I'd suspect that blood sugar and insulin play a role in this, but there could be other mechanisms at play (such as the microbiome).
From the research: "[E]ach additional 10 g/d CHO consumption was associated with an increase of 4 g (95 % CI 1, 7; P=0·003) in birth weight. Conversely, an additional 10 g/d fat intake was associated with a lower birth weight of 8 g (95 % CI 0, 16; P=0·04) when we accounted for energy contributing macronutrients in each model, and maternal height, weight, parity, ethnicity, gestational age at delivery and sex of the baby. There was no evidence of an association between protein intake and birth weight."
I'm not holding my breath for official prenatal nutrition policy to change, but if you are at higher risk for having big babies (family history, prediabetes/gestational diabetes, etc.), take note. It's safe to say your diet should NOT be 45-65% carbohydrates or be restricted in fat, as the guidelines suggest.
