Eating fast food doubles the risk of infertility for women compared to those who eat a lot of fruit, and lengthens by one month the time needed to get pregnant, according to a new study published in the journal Human Reproduction. This work was conducted by midwifery researchers in Australia, New Zealand, the United Kingdom and Ireland on 5,598 women.
Many factors related to parents’ lifestyles have been linked to reductions in fertility, including smoking, excessive alcohol consumption, recreational drug use, and maternal and paternal obesity. Some of them are related to diet, but the specific impacts of maternal diet before conception on fertility remain little studied. Thus, previous studies that found a favorable and significant impact of a healthier diet on fertility examined only infertile women and not the general population.
Fast food consumers have a risk of infertility of 16%, compared to 8% for fruit eaters
For this new study, researchers questioned a heterogeneous population of more than 5,000 women on their diet when trying to get pregnant with their first child. The women who ate the most fruits were defined as consuming at least 3 fruits per day in the month prior to conception. The big fast-food consumers ate hamburgers, pizzas, fried chicken and fries at least four times a week. The researchers found that among women who consumed the least fruit, the risk of infertility (defined as taking more than a year to conceive) increased from 8% to 12%. Among those who ate fast food four times a week, the risk of infertility rose from 8% to 16% compared to fruit eaters. In addition, compared to fruit eaters, other women took 2 more weeks to become pregnant. At the same time, women who ate fast food four or more times a week took almost one month longer than others to become pregnant. “This confirms the protective effect of fruit,” commented the authors in the publication, who on the other hand “found no association with green leafy vegetables or fish.”
An excess of saturated fats toxic to the ovaries
For the authors, the explanation lies mainly in the substances contained in fruits and vegetables, a range of antioxidants and phytochemicals that can have a beneficial effect on fertility. In contrast, fast food contains large amounts of saturated fat, sodium and sugar. According to the authors, studies in mice have shown that excessive intake of dietary fats increases the lipid content of ovarian cells to induce their cell death (apoptosis) by lipotoxicity.
Claire Roberts, a research professor at the University of Adelaide, Australia, said in a statement: “These results demonstrate that a quality diet that includes fruit and minimizes fast food consumption improves fertility and reduces waiting time to get pregnant for women.
” We recommend that women who wish to become pregnant adjust their dietary intake to national dietary recommendations for pregnancy,” said Dr. Jessica Grieger, lead author of the publication and postdoctoral researcher at the University of Adelaide.
A major flaw in the study is its retrospective nature, since women had to remember what they had consumed the month before conception. “For any assessment of dietary intake, caution should be exercised as to whether the recall of participants is an accurate reflection of dietary intake,” commented Dr. Grieger, “However, given that many women do not change diet before pregnancy, we believe that their diet a month before pregnancy is likely to be reasonably accurate.
Finally, the study focused only on a limited range of foods and did not take into account the diet. A recent study cited by the authors of the publication concluded that “higher consumption of fruit and vegetables was associated with increased sperm motility, while higher consumption of foods and sweets high in fat could reduce sperm quality “.