Pros & Cons of Stainless Steel Baby Bottles (VS. Glass or Plastic)

With many parents searching for plastic-free baby bottle alternatives, stainless steel baby bottles are quickly becoming a new trend in bottle feeding. Contrary to plastic bottles that can leach various harmful chemicals and particulate matter into baby’s milk (bisphenol A – BPA is not the only concern with plastic!), stainless steel seems to have a good reputation. Unlike a glass bottle, stainless steel feeding bottle is more durable and won’t shatter on impact.

Is stainless steel bottle the perfect baby bottle? What are the pros and cons of stainless steel baby bottles, and what are the best stainless steel baby bottles on the market? Find out below!

In this article:

• Pros and cons of stainless steel baby bottles
• Does stainless steel leach any toxins?
• Best stainless steel baby bottles
• Summary: Is stainless steel feeding bottle the right bottle for you?

This website uses referral links. Please read our disclosure policy for more information.

Pros and cons of stainless steel baby bottles

The main advantage of stainless steel baby bottles is that they combine some of the positives of glass and plastic.

There is a low likelihood of leaching when used with water, formula milk, or breast milk, and no risk of microparticle shedding with stainless steel, all of which are common issues with plastic bottles. But, stainless steel isn’t completely inert and can leach the metals it consists of, which can sometimes create problems (more on that later).

Unlike glass baby bottles, stainless steel baby bottles are virtually unbreakable and there is no risk of shattering on impact, making them safe for baby’s little hands and your home. Although dropping them can cause dents in the bottle, which can make for an unsightly look and affect accurate measurements if the dent is large enough. (If you’re using an insulated stainless steel baby bottle, a hard drop on the ground can also damage the inner wall and render the bottle useless.)

In addition, similar to glass bottles, stainless steel keeps stink and contaminants at bay since there are no pores on the surface to harbor any sort of outside elements such as bacteria or debris, and it’s easy to keep the bottles clean as stainless steel is tolerant of high heat without any risk of structural damage to the bottle or increased risk of leaching with just heat alone. Most stainless steel baby bottles are dishwasher-safe, except for insulated bottles.

Stainless steel baby bottles are among the highest priced baby bottles on the market (although some glass or silicone bottles are comparable in price), so you’ll have to carefully balance all of the pros and cons and decide if you are willing to pay premium for them. There are definitely some surprising elements to owning stainless steel baby bottles that not all parents are aware of when purchasing the bottles, as discussed below.

Know before you buy:

Some special care will be required with your stainless steel baby bottles. Stainless steel is slow to rust but not rust-proof. Check your bottles often for interior rust marks and discard the bottle if you see signs of corrosion. To prevent rusting, always aim to allow bottles to dry completely after washing.

The biggest downside of stainless steel baby bottles is that the walls of the bottle are opaque, so you can’t see inside the bottle. The measurement lines are etched onto the bottle’s interior. It requires a little more attention to prepare a bottle if you’re using a metal one (not all that fun during the night or early morning hours!), and you won’t know immediately how much is left in the bottle after each feeding. If you need to closely monitor the amount of milk your baby drinks, stainless steel baby bottles may not be the best bottles for you.

HEADS UP! Stainless steel, being a metal, should never be heated in the microwave! Not only does metal reflects microwaves so the heat won’t reach the bottle’s contents, warming stainless steel in the microwave can result in sparking and become a potential fire hazard.

Additional features will depend on whether the bottle is insulated or not.

Insulated VS. non-insulated stainless steel baby bottles: which type is better?

Non-insulated stainless steel baby bottles are lightweight, easy to hold, and won’t add much weight to your diaper bag. They’re fast to warm up but not suitable for use with hot liquids without a silicone sleeve as the metal will instantly become too hot to handle safely. A typical non-insulated stainless steel bottle is dishwasher-safe as long as no special finishes or decorative paint has been used. Generally, smaller bottles (4oz) almost always have no insulation.

An insulated stainless steel baby bottle is constructed with a hermetically sealed inner canister that’s separate from the outer wall. This helps keep the liquids inside the bottle hot or cold for extended periods of time. You will find that some larger metal baby bottles (8z or larger) are offered in both versions, insulated and without insulation. Insulated stainless steel bottles tend to require hand washing since the high heat of the dishwasher could potentially damage the insulation within.

Does stainless steel leach toxins?

Studies show that stainless steel is considerably safer than plastic although not completely inert.

Metal leaching from stainless steel:

Stainless steel is an iron-based metal with added elements such as chromium and nickel, all of which can leach from stainless steel under certain conditions or through regular use.

Out of all metals present in stainless steel, nickel is the most problematic. Nickel is a common allergen, and some nickel compounds have been identified as carcinogenic to humans. Both chromium and iron are beneficial in certain amounts, but excess intake can be problematic.

Studies show that stainless steel cookware can readily leach nickel into acidic foods and drinks, both hot and cold, so it’s best to refrain from adding fruit juices and similarly acidic drinks into stainless steel bottles to minimize exposure to nickel. Brand-new stainless steel seems to be more likely to leach.

That said, stainless steel baby bottles are most likely safe for use with formula milk or breast milk as no leaching of nickel has been observed into these types of liquids. Some chromium will transfer into the milk, but the amounts are very low.

Insider tip: Some recommend boiling new stainless steel bottles in a solution of white vinegar/water (50/50) for several hours to help release some of the surface metals. Just make sure to give the bottle a good rinse afterwards.

Metal leaching relative to stainless steel grades:

Stainless steel comes in various grades. Each grade is classified by its series number and assigned a numerical grade which refers to the amount of chromium and nickel used.

The most widely used is a 300 series, namely grades 304 and 316.

• 304 stainless steel contains a minimum of 18% chromium and 8% nickel (grade 304 18/8). Resulting in great strength and good corrosion resistance, this grade is a popular choice for a wide variety of applications from machinery parts to food processing equipment, kitchen appliances, and utensils.
• 316 stainless steel contains less chromium than grade 304 (around 16%), more nickel (around 10%), and adds molybdenum (2%).
• Stainless steel grades with very little nickel do exist, such as grade 430 which contains less than 1% of nickel. The exclusion of nickel makes 430 stainless steel cheaper to make but also much less resistant to corrosion compared with grades 304 and 316.

Following a review of several brands of stainless steel feeding bottles, all seem to be made with grade 304.

Beware of LEAD!!

Stainless steel is recognized as one of the safest materials for baby feeding accessories that doesn’t leach toxic chemical into baby’s food.

HOWEVER, some *insulated* stainless steel water bottles have been found to contain lead in the welding point at the base of the bottle (the solder between the inner tank and the outer body). Many times these bottles were labeled lead-free.

Lead is a very potent neurotoxin that can irreversibly harm a baby’s health. No level of exposure is safe for babies and small children who are prone to mouthing objects they interact with.

The area of concern on the bottle is normally sealed off from contact with the user, but the solder point can become exposed if the structure of the bottle is compromised, for example after being dropped. Worse yet, with some bottles, based on customer reviews alone, the bottom can reportedly pop off with little force.

Don’t miss: The Best Natural & Non-Toxic Baby Products (2022 Ultimate Guide!)

Again, this issue is only relative to insulated stainless steel bottles. Ordinary stainless steel bottles that aren’t insulated do NOT contain lead components and are perfectly safe to use and for baby to hold.

You are safe using an insulated stainless steel bottle with a lead solder point for the purposes to keep water at an optimal temperature for preparing formula on-the-go. Contamination of the liquids inside is not an issue. As a precaution, check the integrity of the bottle’s base often if you are using insulated stainless steel bottles in your household, and only allow your baby to handle such bottles under close supervision.

Best stainless steel baby bottles

After weighing the pros and cons of stainless steel feeding bottles, perhaps you’ve decided to give them a try. Which stainless steel baby bottles are the best?

Below are the 2 best stainless steel baby bottles I have found that are consistently receiving some of the most positive feedback that you can probably get with a stainless steel bottle (considering the inevitable shortcomings of stainless steel).

Pura Kiki

Buy: Amazon
Cost: $18-28 depending on size and insulation

• Made from 304 (18/8) grade stainless steel
• 100% plastic-free baby bottle!
• Insulated/non-insulated options
• Silicone sleeve included

Admittedly, Pura Kiki is one of the best-known brands for stainless steel baby bottles. Their bottles come in three sizes – 5 oz, 9 oz, and 11 oz. Both insulated and non-insulated options are available, but not across all sizes (the 5 oz and 11 oz bottles have no insulation; the 9 oz bottle is insulated).

Pura Kiki Stainless steel baby bottles are made without any plastic whatsoever! The collar is stainless steel, and the cap is silicone. To my knowledge, this is the only 100% plastic-free baby bottle on the market today. Included is a removable silicone sleeve for a better grip (color options are available).

The nipple is made of medical-grade silicone and features an anti-colic valve to minimize swallowed air. For your reference, the 5 oz bottle comes with a slow flow nipple, and both 9 oz and 11 oz are equipped with a medium flow nipple. As an added benefit, when your baby no longer strictly feeds from a bottle, with the right attachments this baby bottle easily doubles up as a sippy cup, straw cup, or sport/water bottle.

The feedback on these bottles is average, but please understand that stainless steel bottles in general are not rated as highly as other baby bottle types because many parents and parents-to-be buy them not realizing the drawbacks of stainless steel (such as, the volume markings not being readily visible).

Although, in all fairness, there are a few valid functional concerns with Pura Kiki Bottles, such as the smaller bottles (5 oz) having markings up to 3 oz only (instead of 4 oz). If dropped enough times, leaks can develop since the bottle is all-around stainless steel, collar included. The lip of the metal collar is prone to developing rust marks where water gets trapped after washing, as is the bottle itself.

With the insulated bottle you’re also risking exposing your baby to lead if the base detaches and the solder point becomes exposed. Insulated Pura Kiki stainless steel bottles have previously tested positive for lead at the soldering on the inner base.

Thinkbaby

Buy: Amazon
Cost: $13 per bottle on average

• Made from 304 (18/8) grade stainless steel
• Non-insulated
• Dishwasher-safe

Thinkbaby is another popular baby bottle brand for parents with a preference for metal bottles. The bottle is only available in a 9-oz size and comes with a stage A anti-colic nipple made of medical grade silicone (stage B nipples with a faster flow can be purchased separately). Other than that, the cap and collar are plastic.

Again, the most common complaint is that the measurements are hard to see. Thinkbaby bottles are designed with a gentle curve for an easier grip, so some of the lower markings can be even harder to read due to the bottle shape compared with other metal bottles. It may be difficult to track how much milk your baby has consumed if you need to monitor that information. Also, the plastic collar isn’t the sturdiest, and according to many reviewers, the bottle seems to be prone to rusting on the inside shortly after purchasing.

Other options for stainless steel baby bottles that are rated significantly lower include Klean Kanteen and Lifefactory (both non-insulated), or Pacific baby bottle (insulated). All come with silicone nipples.

Final words: Is stainless steel feeding bottle the right bottle for you?

The advantages of using stainless steel baby bottles are clear – they are a safer alternative for your baby than plastic and won’t shatter if dropped like a glass bottle could. If you’re looking for a non-toxic baby bottle without the risk of leaching and want to steer clear of glass, then stainless steel is a great option to consider.

The disadvantages of stainless steel baby bottles include the placement of the volume markings which are embossed into the metal inside the bottle and hard to see compared with other baby bottle materials. There is a chance of denting if the bottle is dropped on a hard surface which can affect the bottle’s stability and/or volume accuracy, and the possibility of rusting if the bottle isn’t allowed to completely dry between uses.

Stainless steel baby bottles are among the safest choices in bottle feeding (although a glass bottle is almost always the safest option!), but keep the following in mind:

• Stainless steel baby bottles are safe for use with water, breast milk, or formula milk. When used with acidic liquids such as fruit juice, metal leaching can occur.
• Closely supervise any contact your baby has with insulated stainless steel bottles (any type) to avoid exposure to lead.
• Stainless steel baby bottles can be safely used with hot water. High temperatures alone do not increase the possibility of the metals leaching into baby’s milk.

Still undecided on which bottles to buy and whether stainless steel is the best baby bottle for your new baby?

Here are other baby bottle options to consider, each with its own set of pros and cons:

• Plastic baby bottles
• Glass baby bottles
• Silicone baby bottles

Hopefully this list of the pros and cons of stainless steel baby bottles helps you decide whether metal baby bottles are the right option for your family.

If you have a question or a concern I haven’t addressed or would like to share your experience with metal baby bottles for other moms and dads to see, feel free to do so in the comment section below.