How to Choose Dog Food: Reading the Label Without the Marketing

A bag of dry food is covered in words designed to sell it: “premium,” “grain-free,” “made with real meat.” What actually determines quality is a specific set of figures the manufacturer is legally required to print on the label. Learning to read them is the only real defence against the marketing copy wrapped around them.

Ingredients: listed by weight, not by quality

Manufacturers must list ingredients in descending order by weight as they went into the mix, that is, before cooking and drying. That single detail trips up most dog owners.

Why “chicken first” doesn’t always mean the most chicken

Fresh chicken is roughly 60 to 70 percent water. It’s listed at its full pre-drying weight, so it easily outweighs dried chicken meal on paper, even though only a fraction of that fresh weight survives once the water evaporates during extrusion. Chicken (or other) meal, by contrast, already sits around 10 percent moisture, so its declared weight is a much closer match to what actually ends up in the finished kibble.

The practical result: a food with two or three meat sources, fresh meat, meat meal, perhaps a named by-product, in the first four ingredients usually delivers more real animal protein than a food where fresh meat sits alone at the top of the list with grains making up the rest.

Here’s the arithmetic. 25 kg (55 lb) of fresh chicken at 70 percent moisture leaves only about 7.5 kg (16.5 lb) of dry matter once the water is gone. If a manufacturer used 25 kg (55 lb) of chicken meal at 10 percent moisture instead, that would contribute about 22.5 kg (50 lb) of dry matter to the finished food, roughly three times as much real protein for the same declared weight. That’s why a food listing “chicken meal” in second or third place isn’t automatically worse than one listing “fresh chicken” first.

Split ingredients

Another trick for pushing a less appealing ingredient further down the list is splitting it into several sub-forms. Instead of one entry for “corn,” the label lists corn gluten, corn flour, and corn bran separately, each with a lower individual weight, so they slot in below the meat even though their combined weight might outweigh it. Add up similar-sounding ingredients yourself before deciding what actually dominates a recipe.

Naming rules tied to ingredient proportion

In Europe and the UK, labelling follows FEDIAF-aligned rules; in the United States, AAFCO’s model regulations serve the same purpose. Both tie the wording on the front of the bag to how much of the named ingredient the recipe must actually contain:

• A bare name such as “Chicken for Dogs” (AAFCO’s so-called 95% rule) requires the named ingredient to make up the large majority of the product.
• “Chicken Dinner,” “Chicken Formula,” or “Chicken Recipe” (AAFCO’s 25% rule) allows a substantially lower proportion, roughly a quarter of the recipe.
• “Dog Food with Chicken” (the 3% rule) requires only a small percentage.
• “Chicken Flavor” requires no set minimum, just enough for the taste to be detectable.

Exact thresholds vary slightly between interpretations and aren’t always printed on the bag, but the general rule holds on both sides of the Atlantic: the closer the wording sits to the plain ingredient name, the higher the required proportion. Read the actual wording on the front of the pack, not just the picture of a chicken.

Analytical constituents: what the numbers actually mean

Below the ingredient list sits a table of analytical constituents, required by law. At a minimum it lists:

Constituent	What it shows
Crude protein	The main building and energy source; digestibility matters just as much, and the table doesn’t show that
Crude fat (oils and fats)	The most concentrated energy source, drives calorie density
Crude fibre	Supports digestion; a high level can be a sign the food is bulked out with a cheap filler
Crude ash	Mineral residue; a high value in a fish-based food isn’t necessarily a problem
Moisture	Usually 8 to 10 percent in dry food, 70 to 80 percent in canned

Notice, too, whether a value is listed as “min” or “max.” Protein and fat are usually declared as a minimum, since they’re desirable and the manufacturer is guaranteeing at least that much is present. Fibre, ash, and moisture are declared as a maximum, an upper limit the food won’t exceed. Actual content can therefore differ slightly from the printed number, generally in the dog’s favor.

Why compare on a dry matter basis

The constituents table shows percentages as fed, including moisture. That means you can’t directly compare a dry kibble at 10 percent moisture with a canned food at 78 percent moisture. The fix is to convert both to a dry matter basis:

% dry matter = (% as fed ÷ (100 − % moisture)) × 100

Example: a kibble lists 22 percent protein and 10 percent moisture. On a dry matter basis that’s 22 ÷ 90 × 100 = 24.4 percent. A canned food with the same 22 percent protein but 78 percent moisture works out to 22 ÷ 22 × 100 = 100 percent on a dry matter basis, which shows how misleading a comparison would be without the conversion. Run this calculation every time you compare a dry food with a wet one, or two dry foods with different moisture levels.

Metabolizable energy and cost per feeding day, not per kilogram

Foods vary widely in energy density, typically from around 300 to over 400 kcal per 100 g. If you’re only comparing price per kilogram of bag, you’re comparing the wrong thing. A cheaper food with lower energy density means you need more of it each day, so the bag runs out faster.

The correct method:

1. Find the metabolizable energy (ME) on the label, in kcal per 100 g. If it isn’t printed, the manufacturer has to know it to calculate feeding guidelines and will provide it on request.
2. Work out the cost per 1,000 kcal: bag price ÷ (bag weight in kg × ME per kg ÷ 1,000).
3. Compare that figure between products, not the price per kilogram.

A food at $5.50 per kg (about $2.50 per lb) with a density of 400 kcal/100 g often ends up cheaper per feeding day than a food at $4.30 per kg (about $1.95 per lb) with a density of 300 kcal/100 g, because you need noticeably less of it. Our food portions calculator works out the exact daily amount in grams for your dog.

Formulas by age and size

Life-stage foods

Puppies, adults, and seniors have different nutritional needs, mainly in the ratio of energy, protein, and minerals. A food labelled “for all life stages” has to meet the stricter requirements of a growing puppy, which means it easily delivers more energy than a low-activity adult dog actually needs.

Large breeds and calcium control

For puppies of large and giant breeds (over 25 to 30 kg, or 55 to 66 lb, as adults), controlled calcium is critical, typically 1 to 1.5 percent on a dry matter basis, with a calcium-to-phosphorus ratio of around 1.2 to 1.5:1. Excess calcium during the rapid growth phase raises the risk of bone and joint development problems, including hip dysplasia. A generic “puppy food” that doesn’t distinguish by size often skips this control and is really intended for small and medium breeds. You’ll find breed-specific detail in our breed profiles.

Grain-free food and the DCM question

The grain-free trend rests on the idea that grains harm dogs, or that grain-free is closer to a wolf’s “natural” diet. Physiologically, that doesn’t hold up: dogs carry more copies of the amylase gene, which breaks down starch, than wolves do, and they digest grains well as a rule. True gluten intolerance in dogs is rare, documented almost exclusively in Irish Setters.

What matters more is what happened between 2018 and 2023, when the FDA investigated reports of increased dilated cardiomyopathy (DCM) in dogs fed grain-free diets long-term, where legumes (peas, lentils, chickpeas) made up most of the protein and starch. The investigation found a statistical association in some cases but did not confirm a direct cause or mechanism. Even so, as a precaution it’s reasonable to:

• avoid formulas as a long-term staple where legumes dominate the first few ingredients,
• talk to your vet about food choice for breeds with a higher genetic risk of DCM, such as Dobermanns, Boxers, and Giant Schnauzers,
• avoid choosing a food based on the “grain-free” trend alone, unless your dog has a specific medical reason for it.

Red flags in the ingredient list

• Vague terms like “meat and animal derivatives” or “meat and meat products” without naming the species. It’s legal, but it stops you judging the quality or digestibility of the source, and it complicates managing a food allergy.
• Added sugar, caramel, or syrups, which in dry food only improve palatability; they add nothing nutritionally.
• Artificial colouring. Dogs don’t perceive the colour of kibble; it’s there purely to appeal to the owner.
• A heavy share of “filler” ingredients high in fibre with no clear purpose, other than lowering calorie density in a genuine weight-management diet.

How to switch foods and know it’s working

Make any food switch gradual, over 7 to 10 days, increasing the new food’s share of the daily ration as you go. A fast switch raises the risk of diarrhoea and vomiting even with a high-quality food, because the gut microbiome needs time to adjust.

You’ll know a food agrees with your dog after 4 to 6 weeks, by:

• formed, regular stools of a reasonable volume,
• a glossy coat without excessive flaking,
• stable body condition that matches the plan, growth in a puppy, steady weight in an adult,
• no itching, recurring ear infections, or excessive gas.

No food is objectively “best” for every dog. It’s always a combination of the formula, how well that individual dog digests it, and feeding the right amount for their age, size, and activity level.