If you’re over 35 and trying to conceive, you’ve probably come across a never-ending list of fertility “rules”—one of the most controversial being whether or not you can drink diet soda. Some claim it’s the worst thing you can consume, while others insist a little won’t hurt.

So, what’s the truth? Is diet soda really a fertility killer, or is it just another overblown myth?

Spoiler alert: Moderation is key.

If you love a fizzy, refreshing diet soda, here’s why you don’t have to banish it completely from your fertility journey. I certainly didn’t!

🚫 The “Diet Soda Will Ruin Your Fertility” Myth

There’s a lot of fear surrounding artificial sweeteners and fertility, but the truth is:
🔹 Most studies linking diet soda to infertility are inconclusive or based on excessive intake.
🔹 One can of diet soda here and there isn’t going to stop you from conceiving.
🔹 Stress about avoiding “bad” foods is often worse than the food itself.

Sure, some artificial sweeteners may not be ideal in large amounts, but an occasional diet soda won’t erase all the other positive steps you’re taking for fertility.

🍹 Why Diet Soda Isn’t the Enemy of Fertility

1️⃣ It Can Help Reduce Sugar Intake

When trying to conceive over 35, managing blood sugar is key—especially if you have conditions like PCOS or insulin resistance.

🔹 Regular soda spikes insulin and increases inflammation—both bad for fertility.
🔹 Diet soda has zero sugar and won’t send blood sugar levels on a rollercoaster.
🔹 Avoiding sugar crashes helps support hormone balance and egg quality.

If diet soda helps you cut back on sugar without feeling deprived, it can actually be a better option than sugary drinks.

2️⃣ Caffeine in Moderation Is Totally Fine

Many diet sodas contain caffeine, and while excessive caffeine may not be ideal for fertility, research shows that moderate caffeine intake (under 200mg/day) is safe while trying to conceive.

🔹 A can of diet soda has around 35-50mg of caffeine—far below the recommended limit.
🔹 If it helps you cut back on high-sugar coffee drinks, it might be a better choice.
🔹 Caffeine only becomes a concern in excess (think 4+ cups of coffee daily).

So, if your one can of Diet Coke gets you through the afternoon without wrecking your fertility, don’t stress about it!

Besides, there are plenty of caffeine-free varieties to choose from if that’s a concern.

3️⃣ It Can Be a Helpful Swap for Sugary Cravings

If you’re trying to eat a balanced fertility diet, you might find that cravings for something sweet and fizzy hit hard. Instead of grabbing a sugary soda, juice, or processed snack, a diet soda can be a calorie-free way to satisfy that craving.

🔹 No need to feel deprived or “perfect” 24/7.
🔹 If it helps you stick to an overall nutrient-dense diet, it’s not the enemy.
🔹 Enjoying a treat without guilt is better than obsessing over “clean eating.”

Balance matters more than perfection.

⚠️ When to Be Mindful About Diet Soda

Of course, just because diet soda isn’t evil, that doesn’t mean you should drink a six-pack a day.

A few things to keep in mind:
🚫 Skip diet sodas with aspartame if you have PKU (a rare genetic condition).
🚫 Obviously, we all know that diet soda is not a replacement for water — hydration is key for cervical mucus, egg health, and overall well-being!

✔ The best approach? If you love diet soda, enjoy it in moderation alongside a healthy fertility diet—just like you would with coffee, dark chocolate, or anything else you enjoy.

🌟 The Verdict: Diet Soda in Moderation Won’t Ruin Your Fertility

At the end of the day, diet soda is not the enemy.

✔ If it helps you cut back on sugar, that’s a win.
✔ If it keeps you from feeling deprived, that’s a win.
✔ If it’s part of an overall balanced approach to fertility, that’s a win.

The real fertility killers? Chronic stress, obsessing over “perfect” eating, and believing you have to eliminate everything you love to conceive.

I had diet soda daily, and my baby girl is healthy, happy, and here 🙂

So, if you want to enjoy an occasional diet soda guilt-free, go for it (unless your healthcare provider says otherwise). 

Your fertility won’t crumble over a can of Coke Zero.

🥤 Are you team diet soda, or do you avoid it while TTC? Let’s chat in the comments!