Moisture content is the percentage of water in a pet food product. It appears on the label as part of the "typical analysis" or "guaranteed analysis" and directly affects how you should read every other nutritional figure on the pack. When moisture is high -as it is in wet and raw foods -the percentages of protein, fat and fibre will look lower than in a dry food, even if the actual nutrient levels are very similar. That's why the numbers don't always add up to 100% in the way you might expect.
Key takeaways
- Moisture content is simply the water percentage in a pet food -and it varies enormously between wet, raw and dry products.
- A higher moisture percentage means the other figures (protein, fat, fibre) will appear smaller on the label, even if the food is nutritionally rich.
- To compare foods fairly, nutritionists use a method called "dry matter basis" -stripping out the water so the nutrients sit on a level playing field.
- Adequate hydration matters for both dogs and cats, and the moisture in food can contribute to your pet's daily water intake. If you have any concerns about your pet's hydration or diet, speak to your vet.
Why doesn't pet food moisture add up to 100%?
Look at the back of most pet food packaging and you'll see a typical analysis listing moisture, protein, fat, crude fibre and ash. Add those figures together and, more often than not, you won't reach 100%. People assume something must be wrong -but nothing is.
The explanation is straightforward. Those listed nutrients are measured independently, and the remaining percentage is made up of items that aren't always declared separately: carbohydrates (often referred to as nitrogen-free extract, or NFE), plus any unmeasured trace components. In other words, the "missing" percentage is simply what's left once the listed figures are accounted for.
According to FEDIAF (the European Pet Food Industry Federation), pet food labelling requirements specify which nutrients must be declared, but manufacturers are not required to list everything in the formulation. So the label is never a complete accounting of every ingredient by weight -it's a regulatory snapshot of the key nutritional markers.
What counts as a "good" moisture percentage in pet food?
There isn't a single correct number -it depends entirely on the format of the food.
|
Food type |
Typical moisture range |
|
Dry kibble |
6–12% |
|
Semi-moist / soft dry |
25–35% |
|
Wet food (tins, trays, pouches) |
70–85% |
|
Raw / fresh food |
60–80% |
These ranges are widely cited by UK Pet Food (formerly the Pet Food Manufacturers' Association), the trade body representing the UK pet food industry.
Each format has its own role, and none is inherently superior to another -what matters is whether the food, as a whole, meets your pet's nutritional requirements.
What you should be cautious about is a moisture percentage that seems out of place for the food format. Very high moisture in a product marketed as semi-moist, for example, might indicate a product that's mostly water with limited nutritional density. Always look at the moisture figure alongside the protein and fat percentages, not in isolation.
Why does moisture content make it hard to compare pet foods?
This is one of the most practical reasons to understand moisture, and it catches a lot of pet owners out.
Say you're weighing up a wet food with 80% moisture against a dry kibble with 10% moisture. The wet food might show 9% protein on the label; the dry food might show 28%. At first glance the dry food looks considerably higher in protein -but that comparison isn't really fair, because the wet food is mostly water.
To put both foods on an equal footing, nutritionists use what's called the "dry matter basis" calculation. It removes the water content entirely so you can see what percentage of the actual food -the solid matter -is made up of each nutrient.
The calculation works like this:
- Take the nutrient percentage from the label (e.g. 9% protein in a wet food with 80% moisture).
- Subtract the moisture percentage from 100% to find the dry matter: 100 -80 = 20%.
- Divide the nutrient percentage by the dry matter percentage: 9 ÷ 20 = 0.45.
- Multiply by 100 to get the dry matter percentage: 45% protein on a dry matter basis.
That 9% protein in the wet food is actually 45% protein on a dry matter basis -considerably more than you might have assumed, and potentially comparable to or higher than the dry kibble.
This is the calculation FEDIAF recommends when comparing foods across different moisture levels, and it's worth keeping in mind whenever you're reading labels.
Does moisture content in pet food actually matter for my pet's health?
It can -though how much it matters depends on your individual pet and what else they're eating and drinking.
For cats, moisture content is particularly worth thinking about. Cats evolved as desert animals and have a naturally low thirst drive. They're physiologically adapted to get much of their fluid intake from food. A dry-only diet means a cat is relying heavily on drinking water to meet their hydration needs, which many cats don't do instinctively. Some vets and feline nutrition researchers note that cats fed exclusively on dry food may have lower overall fluid intake, though this isn't universally agreed upon and individual cats vary enormously.
For dogs, hydration is still important, but dogs tend to be more reliable drinkers and are somewhat better adapted to seeking out water when they need it.
Neither wet nor dry food is automatically better. Many owners feed a combination of both -sometimes called "mixed feeding" -to balance palatability, convenience and moisture intake. There's no single rule that works for every animal, and it's always worth discussing your pet's specific needs with your vet.
Where does Naturo natural pet food sit on moisture content?
Naturo's wet food recipes -available for both dogs and cats -are formulated as high-moisture products, in line with other quality wet foods. This means the water content you see on the label is high (typically in the 75–82% range), which is entirely normal and expected for a tray or pouch format.
What that means in practice is that the protein, fat and fibre percentages shown on the label will look lower than you'd see on a dry kibble pack. That's not a reflection of nutritional quality -it's simply the effect of high moisture content on how figures appear. Once you apply the dry matter basis calculation, Naturo's recipes compare favourably with many other wet food options on the market.
Naturo uses natural ingredients without artificial colours, flavours or preservatives, and its recipes are produced to meet the nutritional requirements set out by FEDIAF guidelines for complete pet foods.
A quick note on "complete" versus "complementary" foods
Moisture content aside, there's another label term worth knowing when you're comparing pet foods: whether the product is labelled as "complete" or "complementary."
A complete food must, by law, provide all the nutrients your pet needs in the right proportions. A complementary food is designed to be fed alongside something else. This distinction appears on UK pet food labels as a regulatory requirement, as set out by UK Pet Food guidance.
Moisture content doesn't determine which category a food falls into -but knowing the difference matters when you're putting together your pet's overall diet.
