Jennifer Hudson's and Megan Fox's respective Paleo and Atkins meal plans work in similar ways.
But the new study suggests that women like Jennifer, Megan and Kim - whose third child, a healthy baby girl named Chicago, was born on January 15 and carried by a surrogate - might want to put their diets on pause for pregnancy.
The study by the University of North Carolina at Chapel Hill was first to evaluate the relationship between low carbohydrate intake and having children with neural tube defects.
Research assistant professor Dr Tania Desrosiers said: "We already know that maternal diet before and during early pregnancy plays a significant role in foetal development.
"What is new about this study is its suggestion that low carbohydrate intake could increase the risk of having a baby with a neural tube defect by 30 per cent.
"This is concerning because low carbohydrate diets are fairly popular," she said.
"This finding reinforces the importance for women who may become pregnant to talk to their health care provider about any special diets or eating behaviors they routinely practice."
The study, published in the journal Birth Defects Research, analyzed data from the National Birth Defects Prevention Study, which spanned 1998 to 2011 and included 11,285 pregnant women from Arkansas, California, Georgia, Iowa, Massachusetts, New York, North Carolina, Texas and Utah.
Of these women, 1,740 had infants, stillbirths or terminations with anencephaly or spina bifida while 9,545 had live born infants without birth defects.
It was found the dietary intake of folic acid among women with restricted carbohydrate intake was less than half of other women.
It is estimated a fifth of US women have blood folate concentrations below the recommended level to reduce risk of neural tube defects.
For this reason, in 1998 the Food and Drug Administration began requiring that folic acid be added to enriched grain products.
While women are urged to take folic acid supplements, up to half of pregnancies are unplanned and many do not start until they found out when a neural tube defect may have already occurred.
This makes fortified foods an important source of folic acid for women who may become pregnant.
Folic acid also known as vitamin B9 is an essential nutrient that minimizes the risk of neural tube defects.
The Department of Health recommends that women should take a daily supplement of 400 micrograms of folic acid while they are trying to conceive, and should continue taking this dose for the first 12 weeks of pregnancy, when the baby's spine is developing.
Rich sources include green, leafy vegetables, brown rice, granary bread, and breakfast cereals fortified with folic acid.