Can Specific Foods Harm Fertility?
As a reproductive endocrinologist helping people build families for over 15 years, I’m answering questions about food and lifestyle daily. The healthier we are, the more our body is focused on reproduction. If you’re wondering what foods you should avoid to maximize fertility, read on.
Foods to avoid for fertility
If you’re like most of my patients, you’re wondering, “What foods should I avoid if I want to be fertile?”
There are four big groups to consider:
Fast food or highly processed foods
Foods with a high glycemic index or high glycemic carbohydrates
High intake of animal protein
Trans fats
Before I get into the details, I want to emphasize that I’m a proponent of finding balance. I do not think fertility (or how we live life) is black and white. I don’t like labeling a food category as “good” or “bad.” In fact, I think it’s okay to enjoy these foods every once in a while as it’s sometimes part of enjoying life.
However, it is essential to focus on the big picture. Choose foods that will be healthy for you most of the time. The healthier you are, the more fertile you'll be.
Fast food
Fast food is highly processed. Its high sodium and fat content is part of what makes it taste great.
But, the data suggest that fast food is generally not good for us—particularly if you’re trying to conceive. A 2018 study published in Australia looked at over 5,000 women who recorded their diets while trying to conceive. Here were the takeaways:
Women who ate a high amount of fast food in their diet took longer to conceive
Women who ate four or more fast food meals per week had a 41% higher chance of being infertile
Fast food has also proven to affect sperm, and a 2015 study concluded that highly processed food is associated with poor sperm parameters.
There are several theories about why fast food is associated with lower fertility rates in both men and women. Food processing (to create “fast food”) often involves removing nutrients. Beyond that, fast food is often high in sodium and sugar, which throws off our metabolisms and insulin levels.
From a preparation standpoint, fast food’s plastic packaging is often full of endocrine disrupters, such as BPA phthalates. (I’ve got some great videos on YouTube that provide detail about endocrine disruptors and their impact on fertility if you’re interested in more information.) If you’re having fast food or takeout, try to remove your food from the packaging as soon as possible to avoid endocrine disruptor absorption.
High glycemic index foods
These foods are typically carbohydrates with refined sugars. The very refined grains cause spikes in our blood sugar, which then spikes our insulin levels, and it’s difficult for our body to quickly recover.
Some foods with a high glycemic index can be white rice, white bread, and instant oatmeal. Corn and some potatoes can have a high glycemic index as well.
On the fertility front, a Nurses’ Health Study found that a higher intake of high glycemic index carbohydrates was associated with difficulty conceiving and, sometimes, ovulatory dysfunction.
You don't necessarily have to cut out carbs completely, but instead, I recommend choosing brown rice, whole grain bread, or steel cut oats. Think about spinach or leafy vegetables as opposed to corn as a side for your dinner.
Every once in a while, these foods are great to enjoy, but when you have the choice, opt for carbohydrates with a lower glycemic index. After all, a 2006 study found that a diet lower in processed carbohydrates could improve sperm parameters.
High intake of animal protein
Studies suggest that a higher intake of animal protein can affect fertility. A study from 2014 showed poor sperm parameters in men whose diets were heavy in red meat. Another study concluded that women who eat a high percentage of red meat as part of their diet have a stronger risk of endometriosis.
There’s more data to suggest reining in protein consumption for improved fertility:
A 2007 study observed the dietary patterns of individuals trying to conceive. People who ate a lot of meat (specifically red meat) took a longer time to conceive and experienced more infertility. The study noticed that ovulatory infertility was lowered by more than 50% when 5% of total calories came from a vegetable protein instead of animal.
Essentially, if you have more vegetable sources for your protein, you’ll have a higher chance of regular menstrual and ovulation cycles, which gives you more opportunity to get pregnant if you're trying to conceive. Non-animal sources of proteins can be vegetables, lentils, nuts, and beans.
I don’t want to take red meat away from everyone’s diets, but thinking about your dietary choices to optimize your fertility can be empowering. Animal protein, specifically red meat, can be heavily processed, contain added hormones or antibiotics, and be stored in endocrine disruptor-heavy packaging. It’s not clear cut, but it’s worth thinking about.
Trans fats
Trans fats are formed when manufacturers use a process called hydrogenation, which turns liquid fats into solid fats to increase a food’s shelf life and stabilize its flavor. So many foods can have trans fats—margarine, cookies, crackers, candies, salad dressing, fried food, granola, bars, and cereals to name a few. Beware of trans fats foods in disguise. Some foods are marketed as healthy, soread the labels.
In a 2007 study, a diet higher in trans fats was associated with ovulatory dysfunction and infertility in a cohort of over 17,000 women followed for 8 years. Increased intake of trans fats has been associated with poor sperm parameters and male factor infertility. Endometriosis is also associated with women who have diets high in trans fats.
My recommendations on foods to avoid
I don’t want to take away the food you enjoy. I think life is for living, and I believe in the power of modifying. My goal is to educate you on healthier choices for your fertility based on evidence. I hope you learned something from this article. If you have any questions or comments, please visit my associated YouTube video.
