I’ll never forget the moment I flipped over my water bottle and actually noticed that tiny little number on the bottom.
You know the one…
That small triangle with a number inside it that most of us have seen a hundred times—but never really paid attention to.
For years, I thought it was just a recycling symbol.
But the more I learned, the more I realized…
That tiny number can tell you a whole lot about what might be coming into contact with your water.
And once I understood it, I started looking at every bottle in my house a little differently.

Before we go any further, grab a plastic water bottle nearby.
Flip it over and look at the bottom.
You should see:
- A small triangle made of arrows
- A number inside (1–7)
Sometimes it’s faint. Sometimes it’s tiny. But it’s almost always there.
That number tells you what kind of plastic you’re using.
And some of them… are better than others.
Where to Find the Number (Most People Miss This)

Let’s Talk About BPA (The Part That Made Me Pause)
When I first heard about BPA, I’ll be honest—I didn’t think much of it.
But then I started digging a little deeper.
BPA (Bisphenol A) is a chemical that’s been used in plastics to make them stronger and more durable.
But here’s what made me stop and think…
BPA is known as an endocrine disruptor, meaning it can interfere with your body’s natural hormones.
Some research has linked it to things like:
- Hormonal imbalances
- Fertility concerns
- Other long-term health effects
Now, I’m not here to scare you.
I’m here to help you be aware—because awareness gives you the power to choose.

What Those Numbers Actually Mean
Here’s the simple breakdown I wish someone had given me years ago:
Better Plastic Choices
- #1 (PET) – Common water bottles (okay for single use, not great for reuse)
- #2 (HDPE) – Milk jugs, sturdy and more stable
- #4 (LDPE) – Softer plastics, generally lower risk
- #5 (PP) – My personal go-to if I’m using plastic
#5 (Polypropylene) stands out because:
- It’s more heat resistant
- It’s less likely to leach chemicals
- It does NOT contain BPA
- It’s commonly used in reusable food containers and bottles
If I had to choose a plastic, I’d reach for a #5 every time.
Use With Caution
- #3 (PVC) – Can contain harmful chemicals
- #6 (PS) – Styrofoam; may leach when heated
The One That Raises Questions
- #7 (Other) – A mixed category
This is where BPA has traditionally shown up most often.
The Truth About “BPA-Free”
Here’s something that really surprised me…
Just because something says “BPA-free” doesn’t always mean it’s completely harmless.
Some manufacturers replace BPA with similar chemicals like BPS or BPF—and we’re still learning how those behave in the body.
So instead of relying on the label alone, I’ve learned to:
Check the number
Avoid heating plastic
Replace containers when they get scratched or worn

What I’m Doing in My Own Home
I’m not about perfection—I’m about progress.
Here’s what that looks like for me:
- I reach for #5 plastics if I’m using plastic
- I’ve started switching to glass and stainless steel when I can
- I never microwave plastic
- I don’t reuse single-use bottles
- I pay attention to wear and tear
It’s not all-or-nothing.
It’s just small, intentional steps.
A Little Food for Thought
It’s kind of wild…
Something as simple as a water bottle can carry so much hidden information.
But once you know what to look for, you’re not just grabbing whatever’s convenient anymore…
You’re making a choice.
And those small choices? They add up over time.
Save This for Later
Next time you grab a bottle of water…
Flip it over.
Check that number.
And just pause for a second—you might be surprised at what you find.
“I always encourage doing your own research—here are a few trusted sources I used while putting this together.”
BPA-Free” Tip
Just because a product says BPA-free doesn’t mean it’s completely free of hormone-disrupting chemicals. Some replacements, like BPS and BPF, may behave in similar ways—so it’s still wise to be mindful of how you use plastic.
What About BPA Replacements Like BPS and BPF?
When I first started paying attention to BPA, I felt relieved anytime I saw the words “BPA-free” on a label.
It sounded like a safer choice.
But then I learned something that made me pause…
Sometimes, when BPA is removed, it’s replaced with similar chemicals like BPS (Bisphenol S) or BPF (Bisphenol F).
And here’s the part that surprised me:
These chemicals are structurally very similar to BPA—which means they can behave in similar ways inside the body.
Why That Matters
BPA became a concern because of how it interacts with our hormones.
It can mimic estrogen and disrupt the body’s natural balance.
And researchers have found that:
- BPS and BPF may also act as endocrine disruptors
- They can interact with hormone receptors in similar ways to BPA
- Some studies suggest they may have comparable biological effects
In other words…
👉 Just removing BPA doesn’t always remove the concern.
What Research Is Showing (In Simple Terms)
Scientists are still studying these replacements, but here’s the general takeaway so far:
- BPS has been shown to affect hormone signaling, even at low levels
- BPF may have similar estrogen-like activity
- These chemicals can still leach from plastic into food or drinks, especially when heated or worn
Now, that doesn’t mean every “BPA-free” product is harmful…
But it does mean the label isn’t the full story.
What I Take From This (And What You Can Do)
For me, this isn’t about fear—it’s about awareness.
Instead of relying on labels alone, I’ve learned to:
✔ Pay attention to the type of plastic (those numbers matter!)
✔ Avoid heating plastic whenever possible
✔ Replace containers that are scratched or worn
✔ Choose glass or stainless steel when I can
And when I do use plastic?
👉 I reach for #5 (polypropylene)—because it’s one of the more stable options and doesn’t contain BPA.
Sources & Research
- National Institute of Environmental Health Sciences (NIEHS) – Bisphenol A (BPA)
https://www.niehs.nih.gov/health/topics/agents/sya-bpa
Explains what BPA is and how it may affect the body as an endocrine disruptor. - U.S. Food & Drug Administration (FDA) – Bisphenol A (BPA): Use in Food Contact Applications
https://www.fda.gov/food/food-additives-petitions/bisphenol-bpa-use-food-contact-applications
Overview of BPA safety, current regulations, and usage in food packaging. - Environmental Protection Agency (EPA) – Bisphenol A Action Plan
https://www.epa.gov/assessing-and-managing-chemicals-under-tsca/bisphenol-bpa-action-plan
Discusses potential risks and environmental impact of BPA. - Harvard T.H. Chan School of Public Health – BPA and Health
https://www.hsph.harvard.edu/ceh/ehs/bpa/
Covers research on BPA exposure and possible links to health concerns. - National Library of Medicine (NIH) – Endocrine Disruptors Overview
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2726844/
Scientific explanation of how endocrine disruptors interact with the body. - Consumer Reports – Is BPA-Free Plastic Safe?
https://www.consumerreports.org/health/food-safety/is-bpa-free-plastic-safe/
Explains concerns about BPA substitutes like BPS and BPF. - Centers for Disease Control and Prevention (CDC) – Bisphenol A (BPA) Facts
https://www.cdc.gov/biomonitoring/BisphenolA_FactSheet.html
Provides data on human exposure and presence of BPA in the population.
So… What Should You Use Instead?
Once you understand what that little number means, you’ll never look at plastic the same way again.
Safer Water Bottle Picks