If you’ve been reaching for diet soda thinking it’s the better choice for your blood sugar, new research may make you think twice, especially if you’re living with PCOS.
A large Australian study just found that drinking one can of an artificially sweetened beverage a day was linked to a 38% higher risk of developing type 2 diabetes. That’s an even bigger risk than regular sugar-sweetened drinks.
When it comes to PCOS, one of the biggest longterm health concerns is insulin resistance, the same metabolic imbalance at the heart of type 2 diabetes (T2DM). That’s why many of us swap sugary sodas for their calorie-free, artificially sweetened cousins.
On the surface, it makes sense: less sugar means less impact on blood glucose… right?
But here’s where the science gets interesting. A new study of over 36,000 Australian adults followed for 14 years found that those who drank one can of a diet soda per day had a significantly higher risk of developing T2DM – even after adjusting for body weight.
In other words, the link wasn’t just about weight gain. And for those with PCOS who already have a higher baseline risk of insulin resistance, this finding might be especially important.
In this post, we’ll unpack what new research has found about artificially sweetened drinks, why this matters if you have PCOS, explore possible reasons diet drinks could affect blood sugar and hormones, and share easy drink swaps along with practical tips to protect your health.
The goal isn’t to create fear around every can of diet soda – it’s to empower you with the science so you can make choices that truly support your hormones, energy, and longterm health.
Let’s dive in!
What the New Study Found
In July 2025, researchers from Monash University in Australia published a long-term study that caught a lot of attention in the nutrition world. They followed more than 36,000 adults aged 40–69 for an average of 14 years, tracking their beverage habits and who went on to develop type 2 diabetes (T2DM).
Here’s the headline:
People who drank one can (about 375 ml) of an artificially sweetened beverage per day – think diet soda, sugar-free energy drinks, or “zero” soft drinks – had a 38% higher risk of developing T2DM compared to people who rarely drank them.
For comparison, those who drank one can of a sugar-sweetened beverage per day had a 23% higher risk.
Even more surprising? The higher risk from diet drinks remained significant after adjusting for body weight. That means it wasn’t just that people who drank more diet soda were more likely to have a higher BMI – something else might be going on metabolically.
The researchers aren’t saying diet drinks cause diabetes – this was an observational study, so it can only show an association. But when you combine these results with other studies (including big reviews of multiple
studies), a pattern starts to emerge: artificially sweetened drinks may not be as harmless as we once thought.
Why This Matters for PCOS
If you have PCOS, your body is already more prone to insulin resistance, meaning your cells don’t respond as well to insulin’s “unlocking” signal.
Over time, this can lead to higher blood sugar levels, more insulin circulating in your system, and greater risk of developing type 2 diabetes.
So if something as simple as our beverage choice might add to that risk, it’s worth paying attention.
That doesn’t mean you need to panic over an occasional diet soda – but it’s a good reason to understand the potential link and explore more hormone supportive go-to drinks.
How Diet Drinks Might Affect Blood Sugar and Hormones
On the surface, artificially sweetened drinks seem like the perfect solution – no sugar, no calories, no spike in blood sugar… right?
But our bodies respond to more than just calories and carbs. Researchers are still piecing together the puzzle, but here are some of the leading ideas about how these drinks could impact metabolism, hormones, and cravings – especially for those with PCOS.
1. They Might Confuse Your Body’s Response to Sweetness
When you taste something sweet, your body starts getting ready to process sugar – even before it actually arrives in your bloodstream.
This is called the cephalic phase insulin response. It’s your body’s way of being proactive: insulin is released to help move the expected sugar into your cells.
The twist? With diet drinks, the sweetness comes without the sugar. Over time, this “false alarm” may confuse your body’s blood sugar regulation system.
Some scientists think this mismatch could lead to less effective insulin signaling – something that’s already a challenge for many people with PCOS. It’s like ringing the dinner bell every day but never serving food – eventually, no one responds to the bell the same way.
2. They May Change Your Gut Microbiome
Your gut is home to trillions of bacteria and other microbes – collectively called the microbiome – that influences digestion, blood sugar, and even hormone balance.
Some artificial sweeteners, such as saccharin and sucralose, have been shown in lab studies to possibly shift the types and balance of bacteria in the gut.
These shifts can make it harder for your body to maintain healthy blood sugar levels and may even promote more inflammation – another factor that can worsen PCOS symptoms.
While not every sweetener affects the gut in the same way, the potential link is worth paying attention to, especially if you already have digestive issues or chronic bloating.
3. They Could Keep Cravings Alive
Sweet tastes light up the reward centers in our brain, making us want more. Even if there’s no sugar involved, regularly sipping something sweet can keep that craving loop active.
For some people, this means they’re more likely to reach for dessert, sweet snacks, or extra portions later in the day.
If you’re working on managing sugar cravings with PCOS, replacing regular soda with diet soda might not solve the root problem – it could just keep the “sweet tooth” switched on in the background.
4. They’re Often Part of an Processed Diet
Diet drinks don’t typically show up alongside balanced, homecooked meals.
They’re often paired with fast food, packaged snacks, or other ultra-processed foods that can raise blood sugar, promote inflammation, and work against hormone balance.
Even if you’re careful with the rest of your diet, drinking diet sodas daily can still be a reminder of old habits – like grabbing lunch on the go or skipping nutrient-dense drinks like water, herbal tea, or homemade smoothies that support your PCOS goals.
Bottom line: None of this means you must swear off diet drinks forever. But if they’re part of your daily routine, it may be worth experimenting with alternatives that better support blood sugar balance, reduce cravings, and protect your longterm metabolic health with PCOS.
PCOS-Friendly Drink Swaps
If you’re starting to wonder whether diet drinks are truly helping you meet your hormone and blood sugar goals, you’re not alone.
The research is still evolving, and it’s okay to have mixed feelings – especially if you’ve relied on artificially sweetened drinks as an alternative to sugar.
This article isn’t here to tell you what you should or shouldn’t drink. Instead, it’s here to give you options – simple, satisfying, and PCOS‑supportive drinks that you can lean on when you’re looking for something refreshing and nourishing.
Whether you’re trying to cut back, explore new routines, or just want a little variety, these swaps are a great place to start.
1. Sparkling Water With a Twist
Sparkling water is a way to the get the bubbles and refreshing feel of soda without the blood sugar confusion or artificial sweeteners.
How to make it fun:
- Add a squeeze of fresh lemon, lime, or orange
- Drop in a few slices of cucumber for a spa day vibe
- Toss in fresh berries or pomegranate seeds for a pop of color and flavor
- Try naturally flavored sparkling waters (look for ones with no added sweeteners – just “carbonated water + natural flavors” on the label)
2. Infused Still Water
Infusing water with fruits, herbs, or veggies can make plain water exciting and help you drink more without added sugars.
Flavor ideas:
- Strawberry + basil
- Pineapple + mint
- Watermelon + cucumber
- Apple slices + cinnamon sticks (amazing in fall!)
3. Unsweetened Iced Tea or Herbal Tea
Tea is rich in antioxidants that can help lower inflammation – something many people with PCOS are working on. Herbal teas are naturally caffeine-free, and you can enjoy them hot or iced.
Fun combos:
- Hibiscus tea with a squeeze of lime (tart and refreshing)
- Peppermint tea for a cooling effect on hot days
- Rooibos tea for a naturally sweet, caffeine-free option
- Green tea with lemon for an antioxidant boost
4. Homemade Electrolyte Drinks
Perfect after a workout or on hot days, without the artificial colors and sweeteners of store bought sports drinks.
Simple recipe:
- 2 cups water
- A pinch of sea salt
- A splash of 100% fruit juice (like orange, pineapple, or tart cherry)
- Optional: a squeeze of lemon or lime
5. Lightly Sweetened Alternatives (When You Need a Treat)
Sometimes you want something sweet, and that’s okay. Choosing natural sweeteners in small amounts can be a good middle ground.
Options:
- Homemade lemonade sweetened with a little honey or maple syrup
- Unsweetened almond milk blended with cocoa powder, cinnamon, and a touch of date
- syrup for a healthy “chocolate milk”
- Smoothies made with lowGI fruits (berries, cherries, kiwi) plus protein and healthy fats for blood sugar balance
6. Bonus: The Mindset Shift
Remember, it’s not about never having a diet drink again – it’s about finding daily go-to beverages that nourish you instead of just filling a craving.
Even swapping one diet soda a day for one of the options above can give your body a break from the constant sweet signal and help your hormones feel more balanced over time.
PCOS Plate Tip: Keep your fridge stocked with at least one premade option (like a pitcher of fruit-infused water or a jug of homemade iced tea) so that when the craving for something fizzy or flavourful hits, you’ve got a hormone-friendly option ready to go.
Bringing It All Together
If there’s one thing I hope you take from this, it’s that you have more power than you think when it comes to supporting your hormones and protecting your longterm health with PCOS.
The goal isn’t perfection, and it’s certainly not about never having a diet soda again – it’s about making choices that help you feel your best most of the time. Small swaps really do add up.
Choosing sparkling water with fresh lemon instead of a diet cola, or sipping herbal tea in the afternoon instead of a sugarfree energy drink, might seem minor in the moment – but over weeks, months, and years, those choices help you create an environment where your body can thrive.
You don’t have to overhaul everything at once. Start with one change. One swap. One little step toward the version of you who feels more energetic, balanced, and in control of your PCOS – not the other way around.
And remember – you’re not doing this alone. Here at The PCOS Plate, I’m all about giving you the science in a way that makes sense for real life, and helping you turn it into practical, doable habits.
If you want simple, evidence-based strategies (and plenty of delicious, hormone-friendly recipes), my ebook The PCOS Plate: Your Guide to Thriving with Polycystic Ovary Syndrome is a great place to start.
Madison is a Registered Dietitian and Certified Diabetes Educator passionate about helping women with PCOS navigate nutrition with confidence. Through science-backed nutrition and lifestyle strategies, she shares practical, sustainable approaches to support hormone health, blood sugar balance, and a healthier relationship with food — one meal at a time.