Senior dog nutrition: how calorie needs change after 7

By Josh · Reviewed and updated: 2026-09-17

A senior dog needs fewer calories than it did as an adult — but the size of that reduction depends on how active it still is, not on how old it is. The figure you will read most often is “15 to 25% fewer”. That range is correct, and it is doing more work than it looks: it is really two different answers for two different dogs. This page separates them, and gives you the amount for each.

What actually changes

Ageing reduces energy requirement through the same three channels it always uses, in reverse:

What does not change is the formula. A senior dog is still 70 × kg0.75 at rest, and then a multiplier — it is only the multiplier that moves.

Where the reduction comes from

This is the part most feeding charts simplify away, and it is worth being precise about, because the site's numbers come from it. The energy multipliers in the NRC Nutrient Requirements of Dogs and Cats (2006) are published in kcal per kg0.75, not as plain multipliers. Two of them apply to older dogs:

NRC 2006 groupkcal / kg0.75Expressed as a multiplier
Older active dogs1051.5× resting energy
Inactive / senior dogs951.35× resting energy

Divided by the resting-energy coefficient of 70, which is how this site converts NRC's figures into its own two-step form. This is the one place where the calculator uses the NRC multipliers directly — see where each factor comes from.

Those two numbers are eleven percent apart, and they point in opposite directions. It is the difference between a dog that still goes for a proper walk and a dog that mostly does not. Treating all seniors as one group — which is what a single “senior” setting does — means feeding the active one less than it needs and the sedentary one more.

“15 to 25% fewer” is not a vague range — it is two precise answers

That is the part most feeding charts simplify away, and it is the reason a range gets quoted where a single number would be more satisfying. The range is not hedging. It is two separate answers for two different dogs, and the variable that decides which one applies to yours is activity.

The important thing about the table below is that each column compares like with like — adult and senior at the same activity level. Figures are engine-calculated at 370 kcal per cup and 110 g per cup, the same basis as the dog feeding chart.

Body weight Typical activity Active
AdultSeniorChange AdultSeniorChange
10 kg187 g158 g15.6%234 g176 g25.0%
20 kg315 g266 g15.6%394 g295 g25.0%
30 kg427 g360 g15.6%534 g400 g25.0%
40 kg530 g447 g15.6%662 g497 g25.0%

Neutered dogs. “Change” is the reduction from the adult figure in the same activity column. The percentage is the same at every weight, because the multiplier is the only thing that moved.

Read the two change columns together and the rule of thumb resolves itself:

Both land inside the familiar “15 to 25% fewer” range. So the range is not vague — it is two precise answers, and the variable that decides which one you get is activity.

The trap: applying 25% to a dog that is still doing 16%. If you take the most commonly quoted figure and cut a still-typically-active senior's food by a quarter, you are feeding it about 11% less than it needs. Over a year that shows up as muscle loss and condition loss, not as weight loss — and in an older dog, muscle is exactly what you are trying to protect. Cut by 16% if the dog is still on its normal routine; 25% only if it has genuinely slowed down.

One qualifier on that 11%, and it matters more than it sounds: it assumes you have the activity level right. If you have also under-estimated how active your dog still is — the more common error, and the one that points in the same direction as this trap — the two mistakes compound. A 10 kg dog that is still genuinely active needs about 176 g a day. Treated as a typical senior and then cut by a quarter, it gets about 140 g: roughly 20% below what it needs, not 11%. Get the activity level right first, then apply the matching reduction.

Judging whether your dog has actually slowed down

This is the honest hard part, because owners systematically overestimate their dog's activity, and a dog that has slowed down rarely announces it. Three things to compare against how your dog was two years ago rather than against an ideal:

Look atGenuinely slower (use 1.35×)Still active (use 1.5×)
Walk duration Shorter than it used to be, or fewer walks The same route and roughly the same time as at five
Stairs, jumps, car Hesitates, or has stopped doing them Still does them without being lifted or helped
Behaviour in the evening Settles early and sleeps more of the day Still initiates play or brings you things

If the dog sits between the two rows, feed closer to which half of the day it applies to, and use body condition rather than any of it to make the final call. The number on this page is a starting point; the dog's ribs are the answer.

Two things that matter as much as the calorie count

1. Muscle, not just fat. A stable weight in an older dog can hide a shift from muscle to fat, because the two can change in opposite directions and cancel out on the scale. That is why body condition scoring matters more in a senior than in a young adult, and why you should also run your hands over the spine and hips — prominent bony points with a covering of fat is a different picture from the same weight on the scale with good muscle over them. The body condition page covers the hand checks.

2. Protein does not fall with the calories. Muscle loss is the main reason a senior's energy requirement drops, so the argument for reducing protein at the same time runs backwards. The usual recommendation is to keep protein the same or slightly higher while the calorie total comes down, which in practice means a senior diet is more protein-dense than an adult maintenance diet at the same number of calories — not simply less of the same food. If a veterinary condition limits protein (kidney disease is the common one), that is a decision for your vet and it overrides this general point.

When weight loss is a symptom, not a feeding problem

An older dog losing weight on the amount that used to hold its weight is a veterinary question. Do not respond by increasing the food. Involuntary weight loss in a senior is a common presentation of dental pain, kidney disease, diabetes, hyperthyroidism in cats, malabsorption or a tumour, and feeding more will not treat any of them. Book the appointment, and bring the weight record with you — a few months of two-weekly weights is one of the most useful things you can hand a vet.

The seven-year mark is a simplification, and here is how big

Worth stating plainly, because the size of your dog changes the answer more than its birthday does. AAHA does not define senior by a fixed age at all. Its definition is relative: the senior life stage is roughly the last 25% of a dog's estimated lifespan. Since lifespan depends heavily on size, that same fraction lands at very different calendar ages:

Breed size (adult)Senior from aboutWhy
Toy and small (under 20 lb)10 yearsLifespan commonly 12 to 16 years
Medium (20–50 lb)9 yearsLifespan commonly 10 to 13 years
Large (50–90 lb)7 yearsLifespan commonly 8 to 12 years
Giant (over 90 lb)5 to 6 yearsLifespan commonly 6 to 10 years

Size-based estimates following the AAHA senior care guidance, which defines the stage as the last quarter of expected lifespan rather than a fixed age. Published thresholds vary between sources — the AVMA, for instance, puts small dogs at about seven — so read this as a directional guide, not a set of precise cut-offs.

What it means for your dog:

This calculator applies seven years by default for every breed. That is a known simplification rather than a judgment about your dog — so if your dog is at either end of the size range, move the threshold accordingly and let activity and body condition settle the rest. The main calculator lets you set the life stage directly. Cats reach senior status later, at about eleven, and the size of their reduction is much smaller — see senior cat nutrition for the comparison.

Frequently asked questions

How much less should I feed my senior dog?

At the same activity level, about 16% less if the dog is still typically active, and about 25% less if it is still active in the sense of doing real exercise. The often-quoted “15 to 25% fewer” covers both cases. If your dog has genuinely slowed down, use the higher end; if it is still on its normal routine, using 25% will underfeed it by about 11%.

At what age is a dog a senior?

This site uses seven years for all breeds. Some guidelines treat large and giant breeds as senior from about five, because they age faster. The more useful signal is activity and body condition rather than the birthday — a seven-year-old still hiking is not the same animal as a seven-year-old that has stopped using the stairs.

Do senior dogs need less protein?

Generally no. Muscle loss is the main reason a senior's calorie requirement falls, so most guidance is to keep protein the same or slightly higher while calories come down. Where a medical condition limits protein, such as kidney disease, follow your veterinarian's plan instead.

My senior dog is losing weight. Should I feed more?

Speak to your vet first. Involuntary weight loss in an older dog is a symptom rather than a feeding problem — dental disease, kidney disease, diabetes, malabsorption and tumours are all common causes. Feeding more does not address any of them, and it delays the diagnosis.

Medical disclaimer. This page provides general information, not veterinary medical advice, and it does not diagnose any condition. Dietary management for a senior with a medical condition should be supervised by a veterinarian.

Calculate your dog's daily amount →
Why puppies need three times the resting energy →
Check body condition as well as weight →
Where each factor comes from →