Can Artificial Sweeteners Negatively Impact Your Reproductive Health and Fertility Outcomes?

Feeling good about that swap to diet soda, right? 

It has zero added sugar, no calories, and it tastes good. Sweet!

But then the voice in the back of your head kicks in and you begin to wonder whether the artificial sweetener in your diet soda is harming your fertility and overall health. 

Do the benefits of consuming fewer sugar calories outweigh the risk of artificial ingredients?

Let’s find out and take a look at whether artificial sweeteners are safe for your fertility.

We know, we know… It’s not exactly breaking news that sugar isn’t considered a health food. 

However, the USDA estimates that the average American consumes almost 60 pounds of added sugar per year — that translates to 13 teaspoons of extra sugar per day, which is equivalent to FIVE glazed donuts. 

Notice we singled out ADDED sugar. 

When it comes to your overall health, we are not as concerned about the naturally occurring sugars found in antioxidant-rich foods like blueberries and your other favorite fruits – assuming you don’t eat a pound of them each day. 

When it comes to added sugar, one of the biggest sources in the standard American diet is high-fructose corn syrup, which is commonly found in soft drinks and fruit juices as well as ketchup, salad dressings, and other unexpected places. If you haven’t stumbled upon any of the work by Dr. Robert Lusting on the evils of high-fructose corn syrup, make sure to check it out. 

As we discussed in our post on carbohydrates and fertility, sugar is a simple carbohydrate that creates a quick and momentary spike in blood sugar and insulin levels. Over time, this pattern can lead to: 

And when it comes to your reproductive health, persistently elevated insulin levels have been associated with:

On top of all this, sugar is also addicting… Ever have a sugar craving? Especially when you’re stressed? That’s because sugar provides your body with an immediate source of energy and serotonin (one of the feel-good chemicals in your brain). 

Okay, we think you get it – that extra sugar intake is not such a good thing for your health.

Now let’s turn our attention to artificial sweeteners…

When it comes to artificial sweeteners, you don’t have to search long or hard for different choices…. Just take a look at the dish of multi-colored packets on the table next time you go out to eat:

The reason that there are so many different artificial sweeteners is that the food industry has tried to appeal to our desire to enjoy sweet foods and drinks without the extra calories. Many had even hoped that these sugar substitutes would have resulted in weight loss while helping address the obesity epidemic.  

Unfortunately, cutting the calories from sweeteners may not provide us with the free pass that we were hoping to enjoy. 

For quite some time, artificial sweeteners have gotten a bad wrap.

Initial scrutiny dates back to the 1970s when studies linked the artificial sweetener saccharin to bladder cancer in laboratory rats. This resulted in a somewhat frightening warning label to be applied to artificial sweetener packets for many years. 

Even though the Food and Drug Administration has declared many artificial sweeteners to be “generally recognized as safe” (GRAS), there is still some concern about what impact they may have on our health. 

Other potential health concerns with artificial sweeteners include an increased risk for:

As with most things in the scientific literature, there are other studies that would suggest no clear differences exist between people who use artificial sweeteners and those who do not. Of course, they also come with the disclaimer that “potential harm could not be excluded”. 

If you’re not starting to take pause over artificial sweeteners, let’s switch gears slightly and look at their impact on reproductive health.

We should be upfront in saying that there are not a significant number of clinical studies available for review on PubMed when evaluating the impact of artificial sweeteners on reproductive health and fertility outcomes.  

As with many areas of emerging research, our initial knowledge has emerged from animal studies. Some of the outcomes of artificial sweetener exposure in animal models include:

Even though they are worth mentioning, these studies must be interpreted with caution. As you know, laboratory research does not always translate well from animals to humans. Moreover, many of the animal studies used significantly higher amounts of artificial sweeteners than any of us would ever consider adding to our diets. 

Moving our attention away from animal studies, there have been a handful of human clinical trials that have evaluated the impact of artificial sweeteners on reproductive outcomes. 

One preliminary study published in Fertility & Sterility by Dr. Halpern and associated has received some attention over the past few years. This study looked at the impact of artificial sweeteners on oocyte quality in 524 women undergoing infertility treatment with in-vitro fertilization (IVF) + intracytoplasmic sperm injection (ICSI). The researchers found that women who consumed beverages with artificial sweeteners had:

There was also a negative correlation when looking at implantation and pregnancy rates, although these results were not statistically significant.

Admittedly, there are some limitations to this interesting study including a lack of information related to the amount of artificial sweeteners consumed by these women, their overall diet quality, or other health factors impacting their fertility (e.g., PCOS, endometriosis, etc.).

In contrast, the PRESTO study, which we discussed in our Decoding the Fertility Diet series, actually found little association between diet soda consumption and time to pregnancy among 3828 women trying to conceive.  

Looking beyond fertility outcomes, artificial sweetener consumption has also been evaluated with respect to preterm birth risk in 2 large studies. 

The Danish National Birth Control investigated artificial sweeteners and preterm birth intake in more than 59,000 women. Compared to no intake, consumption of 1-4 drinks with artificial sweeteners increased the risk of preterm delivery, regardless of body weight, smoking status, or education level (other factors that are associated with preterm birth). 

Similarly, the Norwegian Mother and Child Cohort Study involving more than 60,000 women found that consuming 4 artificial sweetened beverages per day was associated with a significantly higher risk of preterm delivery after controlling for similar confounding factors.

As with most things in medicine, more research is needed on this topic, but there is certainly some information out there to suggest that artificial sweeteners might not be completely harmless when it comes to your reproductive health and efforts to conceive. 

Scientific studies aside, there’s no need to get confused or overwhelmed when it comes to satisfying your sweet tooth. 

Your safest bet when it comes to sweeteners is to choose a natural sweetener in moderation. 

Yes, that pesky, at times not so fun word – moderation!

In all seriousness, why risk your reproductive health by using artificial sweeteners when you can enjoy natural alternatives in a variety of recipes instead? 

Next time you’re in the kitchen, give one of these natural sweeteners a try:

After reading this post, you might not be ready to completely eliminate artificial sweeteners from your diet, especially if you’re a big fan of diet soft drinks.  

With that said, we encourage you to minimize your intake of these additives, the same as you would when it comes to added sugar. And even if present or future nutrition research does not demonstrate definitive harm, artificial sweeteners certainly aren’t helping your fertility. 

Whatever you decide, be mindful of your choices and enjoy what you eat!