Wow, we’re already at the fifth part of my Foods for Fertility series! And it’s time to put down that donut because in this article I’ll tell you about carbohydrates -or carbs- and how they relate to your fertility.
Part 1. The Ultimate Fertility Diet: What To Eat When Trying to Conceive
Part 2. Meat, Poultry, Fish, Tofu: Which Protein is Best and Which is Worst for Fertility?
Part 3. Definitive Guide to Fats That HELP Fertility: Omega-3 and Other Fatty Acids
Part 4. Definitive Guide to Fats That HURT Fertility: Saturated Fats and Other Fats
Part 5. Sugar and Other Carbs Suck When Trying to Conceive
Part 6. Artificial Sweeteners When Trying to Conceive or Pregnant: Bad Idea?
Part 7. Two Reasons Coffee is Bad When Trying For a Baby
Part 8. Can I Drink Alcohol When Trying to get Pregnant?
Part 9. Dairy Can Help You Get Pregnant – Everything You Need to Know
First things first
Before we dive into the specifics of how carbs suck for your fertility, I want to share a bit of background on how it is that scientists can know which foods are good or bad for your fertility.
It’s all, well almost all, thanks to one big study. One of the greatest resources of information on diet and fertility comes from a women’s health study that was started back in the 1970s, the so-called Nurses’ Health Study. Thousands of women participated in this study throughout the years, and a huge part was dedicated to studying the dietary patterns of women who were trying to conceive.
Every two years all these women received a questionnaire about dietary patterns where they were asked whether they were trying to get pregnant and if they had trouble conceiving.
Pretty cool, right? So let’s talk about carbs and fertility :).
The food pyramid
Carbs get a bad rap. I’m sure you’ve heard of low-carb diet as a way of losing weight, but actually, carbs are a really important part of a healthy diet!
Your body converts carbs to glucose, the fuel that gives your body the energy it needs to run (and that’s a good thing!). When your blood sugar is elevated, the hormone insulin is secreted from your pancreas, which in turn helps regulate that elevated blood sugar and keep everything in balance.
Unfortunately, long-term blood sugar elevation can result in what is called insulin resistance, a condition where your bodies’ cells no longer respond well to insulin, even though the pancreas keeps releasing more and more of the stuff. At the end of this cycle, blood sugar levels and insulin levels continue to be high.
Have you ever seen the famous “food pyramid”? Depending on who you ask, carbs are usually somewhere near the bottom. Bread, cereals, oatmeal, sugar, starchy vegetables, beans to name all contain lots of carbohydrates. In other words, most people’s diets are pretty high in carbs. But is that something to be worried about when it comes to fertility, and are all carbs created equally?
Fertility & pastries, snacks, and other yummy carbs
To answer that question, we need to look at how foods rank on the glycemic index. This is a rating system of how foods impact your blood glucose levels. Intake of glucose (sugar) is set to a glycemic index value of 100. And foods are then rated on high much lower or higher they make your blood sugar levels compared to glucose. maybe you’ve heard of glycemic load and not glycemic index, but the idea is the same.
The reason I’m talking about glucose and blood sugar is that there is convincing evidence that women who eat more carbohydrates, especially carbohydrates that are high on the glycemic index (simple carbs) and therefore cause insulin to spike, have an increased risk of infertility due to anovulation.1
The biggest source of added sugars to the average American diet is soda, energy, and sports drinks. Over one-third (34%) of American’s sugar intake, comes from such drinks.2 And a few studies have looked at women’s sugary drink consumption and fertility. And let me tell you, the news isn’t good!
In a 2018 study from Denmark, couples who were trying to get pregnant were followed for 4 years and researchers tracked when women became pregnant.3 Well, it turns out that drinking only sugary 1 soda per day was linked to a 20% lower chance of becoming pregnant. Ouch!
And in an IVF study, women who drank at least one cup of soda per day had 16% lower odds of becoming pregnant.4 It appears that drinking sugary soda pop is associated with have fewer good quality eggs!
There’s one more interesting tidbit that I can share with you: artificially sweetened drinks, such as diet soda, do not seem to impact female fertility! So it seems like you don’t have to completely give up your soda addiction just yet!
But when it comes to fertility, sugar is best avoided or at least limited!
The benefits of eating whole grains
On the other hand, whole grains, such as quinoa, rye, whole-grain bread, brown rice, whole grain pasta, and oatmeal, contain nutrients such as vitamin E and selenium which are good for you because of their antioxidant properties.5
In addition, whole grains can help regulate glucose metabolism and decrease insulin resistance as well.6 In other words, the consumption of whole grains can actually boost your fertility by modulating insulin resistance and reducing oxidative damage of the developing egg, even though whole grains are considered carbohydrates!
A recent study put this to the test and found that among women undergoing IVF, those with higher whole grain intake had a thicker endometrium, the area where the embryo settles and grows, and had lower odds of miscarriage!5
What makes whole grains special
Scientists also found that the beneficial effects of whole grains on getting pregnant are probably driven by just one “component” of the grain.5
So a whole grain consists of several parts. The bran is the tough outer shell of grain and is very high in fiber content. The other parts of whole grains are called the germ (part of the grain which can sprout into a new plant), and the endosperm, which is the energy source of the grain.
Research tells us that it’s eating higher levels of bran is very much associated with better embryo implantation, higher odds of getting pregnant, and better odds of delivering a baby. So if you’re TTC’ing, it’s a really good idea to add oat bran to smoothies, yogurt, or fresh-baked bread.
Carbs, Fertility, and PCOS
I also want to quickly mention something about PCOS, or polycystic ovarian syndrome, which is the most common cause of anovulation. Most women with PCOS have small cysts on the ovaries, higher than normal levels of male hormones called androgens, and insulin resistance. And it’s a known fact that when you have PCOS, getting pregnant is more difficult.
Now, several studies show that for whatever reason the reason may be, women with PCOS tend to eat more high glycemic index foods than women without PCOS.5,7,8,9
So if you know you have PCOS, or you suspect you might have PCOS, you should definitely keep an eye on your simple carb intake, and consider switching to a low glycemic index diet.
Why? Because weight loss through a low-glycemic diet can: increase menstrual regularity, boost fertility, improve insulin sensitivity, and even decrease male hormone levels (androgens)!10,11,12 You see? With PCOS, it’s really important to eat more whole grains and less sugary snacks!
1 Chavarro, J.E., Rich-Edwards, J.W., Rosner, B.A. (2009). Eur J Clin Nutrition. 63(1), 78–86.
2. Drewnowski, A., & Rehm, C.D. (2014). Am J of Clin Nutrition, 100(3), 901–907.
3. Hatch, E.E., Wesselink, A.K., Hahn, et al. (2018). Epidemiology. 29(3), 369–378.
4. Machtinger, R., Gaskins, A.J., Mansur, A. et al. (2017). Fertility and Sterility, 108(6), 1026–1033.
5. Gaskins, A.J., Chiu, Y.H., Williams, P.L. et al. (2016). Fertility and Sterility, 105(6), 1503–1510.e4.
6. Liese, A.D., Roach, A.K., Sparks, K.C. et al. (2003). Am Jo of Clin Nutrition, 78(5), 965–971.
7. Douglas, C.C., Norris, L.E., Oster, R.A., et al. (2006). Fertility and Sterility, 86(2), 411–417.
8. Eslamian, G., Baghestani, A.R., Eghtesad, et al. (2017). J of Human Nutrition and Dietetics, 30(1), 90–97.
9. Altieri, P., Cavazza, C., Pasqui, F. et al. (2013). Clinical Endocrinology, 78(1), 52–59.
10. Moran, L.J., Ko, H., Misso, M. et al. (2013). Human Reproduction Update, 19(5), 432.
11. Gower, B.A., Chandler-Laney, P.C., Ovalle, F. et al. (2013). Clinical Endocrinology, 79(4), 550–557.
12. Mehrabani, H.H., Salehpour, S., Amiri, Z., et al. (2012). J Am College of Nutrition, 31(2), 117–125.