New evidence shows that a plant-based diet may be the most beneficial to reproductive health. Specifically, a high-carb diet rich in whole grains and soy may increase pregnancy and live birth rates, according to a new study published in the medical journal Reproductive toxicology.
The study aimed to review the current evidence supporting the role of nutrition as a modifiable risk factor for female infertility and poor in vitro fertilization (IVF) outcomes.
Current estimates indicate that 15 to 20 percent of couples suffer from infertility, which is defined as the inability to conceive after 12 months of trying. Rising infertility rates have led researchers to become increasingly interested in identifying modifiable lifestyle and environmental factors that may affect reproductive health.
The potential impact of certain dietary patterns, such as the Mediterranean and Western diets, and specific foods on infertility has also been extensively studied.
How foods affect fertility
In this new study, researchers looked at the complex relationship between nutrition and fertility, with a focus on carbohydrates, proteins and fatty acids.
The study found that higher intake of whole grains was associated with higher pregnancy and birth rates. Similarly, eating more vegetables has been shown to improve embryo quality after intracytoplasmic sperm injection (when a single sperm is injected into each egg using a microscopic needle).
Carbohydrate intake and breakdown also appear to regulate ovarian function. In fact, the risk of ovulatory infertility was about 80 percent higher among women who consumed the most carbohydrates than those with the lowest carbohydrate intake in the 2009 Nurses’ Health Study II.
Additionally, a diet with less than 45% of total energy intake from carbohydrates has been shown to improve symptoms of polycystic ovarian syndrome (PCOS) by increasing levels of follicle-stimulating hormone and sex hormone-binding globulin, reducing testosterone and insulin at the same time. levels.
This correlates with low weight in overweight or obese PCOS patients, according to the study. Women with PCOS may not ovulate, have high androgen levels, and have many small cysts on their ovaries.
With a diet in which half of the daily calories come from carbohydrates, more eggs were retrieved and higher rates of clinical pregnancy and live births were recorded in infertile and obese women during IVF.
However, the consumption of sugary soda was also weakly linked to fewer retrieved eggs and embryos obtained from ovarian stimulation cycles, as well as a reduced birth rate.
Animal proteins linked to ovulatory disorders
The study found that animal protein intake was positively linked to ovulatory disorders compared to plant protein. In fact, 5% of energy intake from plant proteins rather than animal proteins has been shown to reduce the risk of ovulatory disorders by more than 50%.
Additionally, soy consumption has been related to better outcomes during IVF.
“There is stronger evidence that animal-based proteins affect female fertility than those [from] plant based [sources]suggesting that the protein source may be an important determinant of reproductive success,” the study says.
The study found no definitive evidence of the impact of omega-3 and omega-6 fatty acids on IVF outcomes. However, better pregnancy odds appear to be related to increased consumption of omega-3 fatty acids, which are found in plant-based foods such as walnuts, flaxseeds, soybeans and canola oil, and are also found in the fish and other seafood.
The study authors note that more research is needed to examine how nutrition is related to increased exposure to endocrine-disrupting chemicals and at what levels to better understand its impact on reproductive function.
“Overall, nutrition appears to represent a modifiable factor that may play a significant role in the context of female reproduction and IVF outcomes, but the limited number of studies and discrepancies between available data warrant further research in the area” says the study. concludes.
Plant-based diet prevents endometriosis
In addition to diet influencing pregnancy rates and outcomes, researchers have looked at how foods affect the female reproductive system in other ways. A study published earlier this year in the medical journal Frontiers of nutrition have found that following a plant-based diet, along with other nutritional interventions such as avoiding meat and consuming seaweed, can help prevent and treat endometriosis.
“Eating meat and fatty foods can lead to an excess of estrogen in the body, which can cause endometriosis pain to flare up, while fiber, found only in fruits, vegetables, grains and beans, can help reduce pain.” eliminating excess estrogen from the body.” Hana Kahleova, MD, PhD, director of clinical research at the nonprofit Physicians’ Committee on Responsible Medicine, said in a statement.
Meanwhile, previous research has noted the benefits of a plant-based diet on women’s menstrual cycles. An analysis of studies that was presented at the North American Menopause Society’s annual meeting last year suggested that diet may be a key factor in menstrual pain (also called dysmenorrhea).
This research has shown that while diets high in inflammatory foods such as meat, oil, sugar, salt and coffee can make pain worse, vegan eating has been shown to tame pain by reducing the inflammation that contributes to it.
Previous research has also found benefits of the plant-based diet on women’s health, such as its ability to reduce menopausal hot flashes. A study published in the journal Menopause from the North American Menopause Society found that a plant-based diet rich in whole soybeans reduced moderate to severe hot flashes by 84%.