Should I Use Fluoride for My Baby or Toddler? What the Science Says
Fluoride can be a hot topic for parents especially when your baby’s first little tooth appears and you're standing in the toothpaste aisle wondering what’s best. Should you go natural? Do babies even need fluoride? Is it safe?
In this post, we’ll break it all down: what fluoride actually does, how it protects little teeth, what the current science says about safety, and the latest New Zealand guidelines. You’ll leave with clarity, confidence, and some great toothpaste recommendations too. And if you're a parent using tank water, you’ll also learn how to ensure your little one is still getting the dental protection they need.
What Is Fluoride and Why Does It Matter?
Fluoride is a naturally occurring mineral found in water, soil, and some foods. It plays a key role in strengthening tooth enamel and preventing decay. For little ones, fluoride is especially important because it protects baby teeth and good oral health in childhood lays the foundation for lifelong health.
Fluoride works by helping to repair early signs of decay, making enamel more resistant to acid, and reducing the growth of harmful bacteria in the mouth. And because baby teeth have thinner enamel than adult teeth, they’re more vulnerable to decay making early protection critical.
In fact, research shows:
Children in fluoridated areas experience up to 40% fewer cavities.
Using a fluoride toothpaste reduces the risk of tooth decay by about 24%, even in areas without fluoridated water.
Communities with access to fluoridated water have better oral health outcomes, especially in low-income populations where access to dental care may be limited.
So yes fluoride matters. It’s one of the most effective and affordable tools we have for protecting teeth, and it starts working from the very first brush.
Is Fluoride Safe for Babies and Toddlers?
Absolutely when used correctly. It’s natural to be cautious, especially when something is going into your baby’s mouth every day. Let’s take a closer look at the most common concerns and what the research actually says:
Dental Fluorosis
This is a common concern. It causes faint white streaks on adult teeth if a child swallows too much fluoride under the age of 5. It doesn’t harm baby teeth and is purely cosmetic. Prevent it by using the right amount:
A tiny smear (about a grain of rice) under 3 years
A pea-sized amount from age 3–5
Being consistent with the amount and supervising brushing makes fluorosis very unlikely.
Fluoride Toxicity
Swallowing an entire tube of toothpaste could be dangerous but with proper supervision and storage, fluoride toxicity is extremely unlikely. The good news is that the small amounts used for brushing are very safe and beneficial.
Brain Development
Some concerns have been raised about high fluoride levels affecting IQ but this is from areas with 2–4x higher fluoride levels than what we have in New Zealand. Our water supply is carefully regulated (0.7–1.0 mg/L), and NZ’s Ministry of Health confirms it is safe. Large scale research consistently shows no adverse cognitive outcomes from community water fluoridation.
So in short: when used as recommended, fluoride is both safe and incredibly effective.
What the New Zealand Guidelines Say
Fluoride in water has been used here since the 1950s. In 2022, the Director-General of Health gained authority to require local councils to fluoridate water supplies backed by strong research showing significant benefits for children’s oral health.
The Ministry of Health recommends:
Brushing with fluoride toothpaste (at least 1000ppm) from the first tooth
Avoiding low-fluoride toothpastes—they don’t offer enough protection
For families on tank water, fluoride toothpaste is especially important
These recommendations are part of a broader effort to reduce dental health inequities and support better outcomes for all New Zealand children.
Daily Fluoride Tips for Parents
Here’s how to keep things safe and effective:
Start brushing when that first tooth pops through (around 6 months)
Use a grain-of-rice-sized smear under age 3
Switch to a pea-sized amount from age 3
Supervise brushing until at least 8 years old
Don’t rinse with water just spit out the excess to keep some fluoride on the teeth
Store toothpaste out of reach to avoid accidental ingestion
Make brushing a part of your daily routine after breakfast and before bed
Tip: Singing a song, using a sticker chart, or letting your child choose their toothbrush can help make brushing more fun and consistent.
Great Toothpastes for Kiwi Kids
Not all kids’ toothpastes are created equal. Look for at least 1000ppm fluoride. Here are some trusted options:
Grin Kids with Fluoride – Natural, NZ-made, gentle flavours and free from SLS
Red Seal Kids with Fluoride – Berry-flavoured and free from harsh chemicals
Colgate Kids – Trusted brand with kid-friendly appeal and full fluoride protection
Avoid fluoride-free or low-fluoride options unless advised by a health professional. While they may be marketed as “natural,” they don’t provide the proven cavity protection fluoride offers.
What About Tank Water?
If your family uses rainwater or tank water, there’s no fluoride in your supply. This means your child may be at higher risk of cavities, and using fluoride toothpaste becomes even more essential.
Families on tank water may also want to:
Ask your dentist about fluoride treatments
Avoid relying on low-fluoride products
Monitor your child’s oral health closely
If you’re concerned, talk to your GP or dentist.
Summary: What Parents Need to Know
Fluoride is safe and effective when used correctly.
It reduces cavities and strengthens enamel even in babies.
New Zealand guidelines recommend fluoride toothpaste from first tooth.
Choose toothpastes with at least 1000ppm fluoride.
Brush twice a day, supervise, and make brushing fun and routine.
Tank water families should be extra mindful of using fluoride toothpaste.
Final Thoughts
As a mum and a dietitian, I know how overwhelming the early years can be especially when it feels like there’s a new decision to make every day. But fluoride doesn’t need to be one of them. The science is strong, the guidelines are clear, and the benefits are lasting.
You’re doing an amazing job. And brushing with fluoride? That’s just one more way you’re setting your little one up for a healthy, happy future.
Looking for more baby and toddler feeding tips? Come say hi on Instagram @juliascott_dietitian or check out more resources on juliascott.co.nz.