Low carb, high protein diets improve fertility


The results of a study examining the effects of a low carbohydrate, high protein diet on fertility were announced at the Annual Clinical Meeting of The American College of Obstetricians and Gynecologists in New Orleans. Dr. Jeffrey B. Russell headed the research at the Delaware Institute for Reproductive Medicine (DIRM) in Newark. An evaluation of women being treated with in vitro fertilization (IVF) found that those who maintained a low carbohydrate, high protein diet had better quality ova and embryos. Dr. Russell stated that the research also provided evidence that a diet consisting of 25 percent or more protein and less than 40 percent carbohydrates improved pregnancy rates four times over women that consumed more carbohydrates and less protein.

An assisted reproduction therapy program was offered at DIRM between January 2010 and December 2011. The 120 participants were asked to complete a three day nutritional log prior to receiving an embryo transfer. An evaluation of the logs found that 48 patients consumed a daily average of 25 percent or more protein while the diets of 72 percent were composed of less. Observations of the developing embryos found that after five days, increased blastocyst formation had occurred in 54.3 percent of patients with a protein intake of 25 percent or greater. Those with lower protein consumption experienced 38 percent blastocyst formation.

Dr. Russell alluded to the common credence that the body mass index (BMI) is often implicated in poor infertility. His observations were that poor quality embryos occurred among both thin and healthy women. The study was initiated to determine the nutritional effects on fertility and the developing embryo. As a result of the study, Dr. Russell now requires patients to maintain a diet of 25 percent or more protein and less than 40 percent carbohydrates for three month prior to beginning in vitro fertilization treatment.

Dr. Kathy Hoeger, Director of the Strong Fertility Center at the University of Rochester, N.Y., stated that there were other factors that may have affected the results of the low carbohydrate, high protein diet fertility study. Dr. Hoeger explained that reliable scientific evidence on the connection between diet and fertility is limited. Much of the research has been deduced from animal studies, and the processes linking diet to the quality of ova are not thoroughly understood. She said that dietary intake is important and shouldn’t be dismissed, but there isn’t enough conclusive evidence to claim that a diet of a specific amount of protein or carbohydrates should be followed. It is clear that dietary extremes may be harmful.

One of the most meticulous studies relating carbohydrate intake to fertility was performed at Harvard University in 2007. Researchers evaluated data from over 18,000 women who took part in the Nurses’ Health Study. It was one of the lengthiest studies of women’s health to ever take place in the United States. The results were published in the highly publicized book, “The Fertility Diet”. Harvard researchers concluded that a diet low in trans fats and high in fiber provides the best nutrition to enhance fertility. They stated that women should concentrate on the quality of the carbohydrates consumed rather than restricting them. The study also noted that women who consumed whole full fat dairy products had fewer problems conceiving than those who used skim or low-fat alternatives. The Harvard study, like the new study, also has limitations. Although it was extensive, it was purely observational and researchers drew conclusions from the data. They had no means of testing their theories.

While most experts warn against narrowly interpreting the results of the study, they did agree that it does demonstrate the importance of proper nutrition in conceiving. They caution against women with fertility problems consuming large amounts of steak eggs and high protein snacks since dietary extremes have been found to be unhealthy. Dr. James Grifo, program director at the NYU Fertility Center in New York City, said that he thought the study exemplified the necessity of eating healthy during fertility treatments. He stated that while there were many things that were beyond the patient’s control, eating properly was within their capabilities. He also advised against “over interpreting” the results.

The study’s findings are considered preliminary until published in a peer reviewed journal. Dr. Grifo noted that the subject group of the study was limited. The study also did not conclude why the women who consumed higher amounts of protein had a higher in vitro fertilization rate. He said one probable explanation could be that women who included more protein in their diet consumed fewer empty calories from processed foods. Processed foods frequently contain large amounts of simple sugars. In theory, simple sugars can affect the production of insulin and other hormones and hamper the ability to conceive.

Kim Ross, a nutritionist at NYU Fertility Center said she found the results of the new study interesting. She also feels the study emphasizes the need for proper nutrition while fertility treatment is being administered. She added that she doesn’t want patients to interpret the study to mean that they should consume large amounts of animal products and high protein snacks. Ross says the outcome of the research at DIRM may have been due to the fact that the women with a higher protein diet also consumed more whole foods. The American diet usually consists of a large percentage of processed foods. Most processed foods have poor nutritional value.

Other studies also support the idea that a well-balanced, nutritious diet promotes fertility. Researchers recently reported that those who followed the Mediterranean diet had a higher probability of conceiving than those who consumed the standard Western diet, in both women being treated with in vitro fertilization and those attempting to conceive naturally. The customary Mediterranean diet consists of very little red meat, dairy and processed foods. It is comprised mainly of fresh fruits and vegetables, fish, olive oil and whole grains. Ross and Grifo pointed out that monounsaturated and polyunsaturated fats found in vegetable oils as well as fruits and vegetables are essential to a healthy diet for everyone, especially women undergoing fertility treatments. Ross stated that although the current research concentrated on women, diet also affects the sperm quality of men. Therefore, she counsels both men and women seeking infertility treatment.