Whats in a Bowl?

As raw and natural feeders, our primary concern is obviously what we put in our dog’s bowls. But have you ever stopped to consider the bowl itself? Are some bowls better than others? Can bowls have an impact on your dog’s health? And how do you choose the right bowl for your dog? 

In this blog article, we'll aim to answer all these questions. To do this we’ll complete a detailed assessment of the three most common types of feeding bowl – being: plastic, ceramic and stainless steel. We’ll also briefly discuss the following less common alternatives: glass, silicone, bamboo, melamine and aluminium.

Key factors to consider when selecting a dog bowl

To ensure a balanced and consistent evaluation of each bowl type, we’ll assess each against the following eight factors:

1. Toxic impact: Is there a risk that the bowl contains toxic chemicals that could leach into food/water?
2. Safety: Does the bowl pose any form of physical safety risk (such as breaking or choking)?
3. Allergies: Is there a risk that the material of the bowl might cause allergic reaction?
4. Hygiene & ease of cleaning: Is the bowl easy to clean? And can mould and bacteria easily grow on its surface?
5. Durability: Is the bowl tough wearing and long-lasting?
6. Affordability: Is the bowl budget friendly?
7. Weight: Is the bowl light or heavy weight (noting that both can be advantageous – depending on intended use)?
8. Variety and aesthetics: Is the bowl available in different sizes, shapes and colours?

To complete an assessment, we’ll provide a rating of good (2 points), ok (1 point) or poor (0 points) against each of the eight factors. This will then allow us to provide an overall rating out of 16 (being the maximum possible number of available points). The best bowl will be the one with the highest number of points.

Plastic dog bowls

Plastics are derived from organic materials such as crude oil, natural gas, salt and coal. These ingredients are made into plastic via a process called polymerisation. There are many different types of polymer plastics, all of which have different properties and characteristics. Because they are cost effective and come in a range of sizes, shapes and colours, plastic dog bowls are popular and widely used.

• Toxic impact – poor: Many plastics contain harmful chemicals such as Bisphenol A (BPA). BPA is a xenoestrogen, which means it disrupts the endocrine (hormone) system and can contribute toward the development of diseases such as diabetes, cancer and neurological problems (in both animals and humans alike). And to make it worse, studies have found that even BPA-free plastics can contain other forms of hormone disrupting xenoestrogens (1).
• Allergies – poor (potentially): Some dogs are allergic to plastic. A plastic allergy can result in conditions such as Contact Dermatitis or Plastic Dish Nasal Dermatitis. Where the symptoms of Contact Dermatitis are bumps, blisters, raised itchy bumps and red skin (which will usually appear on the nose, mouth and chin). And the key symptom of Plastic Dish Nasal Dermatitis is loss of pigmentation around the nose and mouth (i.e. a black nose gets pink patches)(5).
• Safety - poor: Plastic can be easily chewed. If your dog chews and swallows pieces of hard plastic, they are at risk of internal damage and/or obstruction.
• Hygiene - poor: If not cleaned well, scratches and cracks can harbour harmful bacteria such as E. Coli and salmonella. In certain quantities, these bacteria can make your dog very ill.
• Durability - poor: Plastic bowls are not long lasting as they are prone to scratching and cracking (especially if left outdoors). 
• Affordability - ok: Plastic bowls are generally low cost, but keep in mind that you’ll need to replace them more frequently, which makes them less cost effective in the long run.
• Weight - good (if you want lightweight): Plastic is lightweight, making it easy to transport and move around.
• Variety & aesthetics - good: Plastic bowls come in a wide range of sizes, shapes, colours and designs.

Overall rating = 5/16

Overall, the risks associated with plastic feeding bowls outweigh the benefits. But if you are considering a plastic bowl, make sure you choose food grade plastic and avoid recycled plastic. You will also need to thoroughly wash and dry the bowl after each use and check it regularly for scratches and cracks. Never heat the bowl. If the bowl becomes damaged in any way or has a strange or unpleasant smell, ditch it, and get a new one.

Ceramic dog bowls

Ceramic bowls are generally made from a mixture of clay, earthen elements, powders and water. They are shaped and then hardened by the application of heat. To prevent them from absorbing moisture, most ceramics are sealed with some form of glaze. Like plastic dog bowls, ceramic bowls are aesthetically appealing as they can be made into a wide range of shapes, sizes and colours.

• Toxic impact – ok (depends): Some ceramics are sealed with lead-based glaze. If ingested, lead substitutes itself for calcium and zinc in the body (which are both essential minerals for normal cell function) and lead poisoning can occur. Lead poisoning is characterised by gastrointestinal upset, neurological changes, blood abnormalities, immunosuppression, infertility and kidney disease(2).
• Allergies - ok: Apart from the lead issue, the risk of allergies arising from ceramics is low.  
• Safety - ok: While your dog is unlikely to attempt chewing a ceramic bowl, ceramic bowls can shatter if dropped. This poses a risk if your dog decides to run off with a piece of bowl in his mouth or to jump on a sharp piece of broken ceramic.
• Hygiene - poor: Most ceramics are dishwasher safe, which makes them easier to clean. But they can retain odour of not cleaned properly. And like plastic bowls, ceramics can develop hairline cracks that harbour bacteria and mould. In fact, a study done by Hartpury University found ceramics to be the worst offenders when it comes to growth of harmful bacteria in dogs’ water bowls(4).  
• Durability - ok: Ceramic bowls are moderately robust and long lasting, but they can crack; and they are likely to shatter if dropped. 
• Affordability - good: While usually more expensive than plastic, ceramic bowls are generally ‘middle of the range’ when it comes to cost.  
• Weight - good (if you want heavyweight): Ceramic is heavyweight, making it a good option for dogs that eat vigorously and try to push or flip their bowls.
• Variety & aesthetics - good: Ceramic bowls come in a wide range of sizes, shapes, colours and designs.

Overall rating = 10/16

Overall, ceramic bowls provide a budget friendly, heavyweight and easy-to-clean option. They could be an option to consider if your dog is a vigorous eater and ‘bowl flipper’. However, ceramics can crack and shatter, and there is a risk of exposing your dog to lead. If you decide to go for a ceramic bowl, make sure it’s lead free. Look for non-toxic, dishwasher safe and microwave safe labels. You’ll also need to frequently check the bowl for cracks and damage.

Stainless steel dog bowls

Stainless steel is made from iron, carbon, and alloying elements such as chromium and nickel (where the addition of alloying elements provide resistance to corrosion). Stainless steel dog bowls are known for their durability and hygiene.

• Toxic impact - good: High grade stainless steel is a non-toxic material. Just make sure you choose a ‘food grade’ stainless steel (which are the 200 and 300 series).
• Allergies - good: The risk of allergies arising from stainless steel is extremely low. However, some dogs can be allergic to nickel and/or chromium. Hairless breeds are most susceptible. The symptoms of nickel and/or chromium allergy include skin lesions & bumps, irritation & redness; loss of fur; and change in skin pigmentation (colour)(3).
• Safety - good: Stainless steel is chew, scratch, crack and shatter proof.
• Hygiene - good: Stainless steel is extremely hygienic. All food grade stainless steel bowls are dishwasher safe. And because stainless steel doesn’t scratch, crack, corrode or rust, bacteria and mould cannot easily grow on its surface.
• Durability - good: Stainless steel is highly durable and long lasting.   
• Affordability - ok: Price varies according to the type of bowl. Basic single layer stainless steel bowls are generally well priced. Double insulated non-slip bowls tend to be more expensive.  
• Weight - good (depends on style and intended use): As mentioned above, there are different styles of bowl. The basic single layer style is lightweight – making it ideal for travel or less vigorous eaters. Double insulated bowls are heavier, wider and usually have a non-slip ring on the bottom – making them suitable for vigorous eaters and ‘bowl flippers’.  
• Variety & aesthetics - ok: There are less colour and design options for stainless steel – but there are still many attractive options available.

Overall rating = 14/16

Overall, stainless steel bowls rate highest as they’re non-toxic, safe, hygienic and highly durable. If you decide to go for a stainless steel dog bowl, make sure it’s food grade quality (200 or 300 grade series) and dishwasher safe. Be sceptical of any brands that don’t provide their stainless steel grade or if they’re labelled as ‘hand wash only’ or ‘for pet use only’.

Alternative types of dog bowl

For completeness, we’ve included a brief discussion on the following less common bowl alternatives: glass, silicone, bamboo, melamine and aluminium.

• Glass – glass bowls are non-porous, easy to clean, hygienic and hypoallergenic. However, as they’re easy to break, they pose a safety risk – especially for highly active dogs and vigorous eaters. Glass bowls are a good option for small, less active and/or allergy prone dogs.
• Silicone – food grade silicone is dishwasher safe, non-toxic and can safely withstand high temperatures. However, given its soft and pliable texture, silicone can be easily chewed and is not practical for everyday use. Silicone bowls are ideal for occasional use whilst travelling.
• Bamboo – bamboo bowls are durable, non-toxic, have natural anti-bacterial properties and are generally dishwasher safe. Bamboo bowls are however lightweight, not always readily available and tend to be more expensive. Bamboo bowls are a good choice for non-vigorous eaters.
• Melamine – melamine is an alternative to plastic (used in kitchen and restaurant ware). It is durable and virtually unbreakable. However, melamine releases toxic chemicals if heated, it needs to be handwashed and is usually expensive. On balance, the risks outweigh the benefits; and with numerous better options available, melamine bowls are probably best avoided.
• Aluminium – aluminium bowls are durable and easy to clean. However, some bowls are ‘untreated’, which means your dog will be exposed to toxic levels of aluminium. And if the bowl has been treated (or anodised), it is less durable and not dishwasher safe. Much like melamine, aluminium bowls are best avoided.

What about bowl shape and size?

When choosing bowl size and shape, you should also consider the following factors:

• Physical characteristics: Different dogs have different physical characteristics that may impact how they eat. For example: giant/large breeds may benefit from elevated bowls to help the flow of food and water down their oesophagus. And flat-faced breeds benefit from wide and shallow bowls so that their breathing is not further constricted.
• Behaviour: Some dogs are prone to scoffing their food at such speed that they make themselves sick! Such dogs benefit from ‘slow feeder’ bowls or ‘lick mats’ (just note that most of these bowls and mats are made from plastic, so select carefully). Other dogs get so enthused about their dinner that they push their bowl from one side of the room or flip it over. These dogs may benefit from heavier bowls (ceramic) or those that incorporate some form of non-slip base (often stainless steel).
• Portion size: Most bowls come in a range of sizes, but choosing the right size helps to manage portion size, thus promoting healthy eating habits and preventing overeating. But if you want to be sure - weighing and measuring your dog’s food is the most reliable way to manage his/her portion size.

Conclusion

If you put your dog’s health and wellbeing ahead of all else (including cost) and you want a highly durable, non-toxic, hygienic, safe and ‘easy to manage’ bowl – food grade stainless steel is the clear choice. Bamboo is also a contender, but as a relatively new product, is not yet well tested or backed with substantial evidence/research. Glass is a great option if the risk of breakage is low, and you’re not worried about limited variety and aesthetics. And silicone is a good choice for travel but isn’t practical for everyday use.

On the basis that risks outweigh the benefits, especially when it comes to health & safety – plastic, ceramic, melamine and aluminium bowls are probably best avoided (unless you can be sure of quality and follow careful cleaning and maintenance procedures).

If you’re looking for a food grade (304 grade) stainless steel bowls in a range of sizes and modern colours – check out the Led & Collared Dog Feeding Bowls.

We also love these... Dog Feeding Mat | Led & Collared NZ (ledandcollared.co.nz)

References:

1. Barry R. Blakley, DVM, PhD, Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan.
2. Peter Dobias, DVM. https://peterdobias.com/
3. Wag Walking. https://wagwalking.com/
4. Aisling, C. (2019). Microbiological Assessment of Canine Drinking Water and the Impact of Bowl Construction Material. Department of Animal and Agriculture, Hartpury University.
5. Animal Wellness Magazine. https://animalwellnessmagazine.com/

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