Feeding your senior cat: what changes after 10
Cats don't stay the same animal throughout their lives. The confident, athletic adult who once leapt onto every surface without a second thought becomes, at some point, something different: a creature who moves a little more deliberately, sleeps a little more, and whose body has quietly changed in ways that affect what it needs from food.
After around age 10, those nutritional needs shift enough that what worked perfectly for years may no longer be enough. Here's what changes, and how to feed your senior cat well.
When does a cat become 'senior'?
The exact definition varies by vet and organisation, but most agree that noticeable metabolic changes begin from around 7 to 8 years old, even if a cat still looks and acts young. By 10 to 12 years, a cat is considered officially senior, and from 15 onwards, geriatric.
Life expectancy for indoor cats is typically 13-17 years, with many reaching their late teens or even early twenties. That means a 10-year-old cat may have a third or more of their life still ahead of them: plenty of time to benefit from a diet that supports how their body actually works at that stage.
How nutritional needs change with age
Several shifts happen as a cat ages, and they don't all point in the same direction:
More protein, not less
This surprises many owners. Older cats actually need more protein than younger adults, not less. From around age 12, a cat's ability to digest and absorb protein decreases: a phenomenon called reduced digestive efficiency. If protein intake drops to match reduced activity, muscle mass is lost faster than it would be in a younger cat. Senior cat foods with high-quality protein (ideally at least 30-35% dry matter) help maintain muscle condition and body weight.
Fewer calories: but not always
From roughly age 7 to 11, many cats become less active and put on weight more easily. Calorie intake may need to come down during this middle-senior phase. But from around age 12, the opposite often happens: older cats can struggle to maintain weight even when eating normally. Their digestive system becomes less efficient at extracting energy from food. Weight loss in a senior cat isn't something to accept as inevitable: it's worth investigating and addressing.
More water
Kidney disease is the most common cause of death in older cats, affecting roughly 30-40% of cats over 15. One of the most effective things you can do to support kidney health is increase your cat's water intake. Senior cats on wet food consume significantly more water than those eating dry kibble, which is why many vets recommend switching to or increasing wet food as cats age. Cats also have a low thirst drive by nature: they evolved in dry climates and tend to get most of their water from food, not from a bowl.
Phosphorus management
The kidneys filter phosphorus from the blood. When kidney function declines, phosphorus builds up, accelerating further damage. Senior cat foods: particularly those marketed for kidney support: are formulated with reduced phosphorus. For cats in early kidney disease, a low-phosphorus diet can meaningfully slow progression and improve quality of life.
Signs the current diet might not be working
Watch for these signs that your cat's nutritional needs aren't being met:
Gradual weight loss despite eating a normal or increased amount
Muscle wasting, particularly around the spine and hindquarters: you can feel the vertebrae more easily than before
A dull, dry, or unkempt coat
Reduced energy or reluctance to groom
More frequent vomiting or loose stools
Drinking noticeably more water than usual
Leaving food that used to be eaten readily
Some of these signs can point to specific conditions: hyperthyroidism, diabetes, dental pain, or kidney disease: that go beyond diet alone. If you notice several of them, a vet check is the right next step.
Practical tips for feeding your senior cat well
Switch to a senior-specific food from age 10 onwards. These are formulated with higher protein, lower phosphorus, and often added supplements like omega-3 fatty acids and antioxidants that support ageing joints and immune function.
Prioritise wet food. Even if your cat has always eaten dry food, introducing wet meals (at least 50% of their diet) makes a meaningful difference to hydration and kidney health. Warm the food slightly: older cats often have a reduced sense of smell, and warmth helps release aromas that stimulate appetite.
Offer smaller, more frequent meals. Older cats often do better with 3-4 small meals rather than 1-2 large ones. Digestive efficiency decreases with age, and smaller amounts are processed more easily.
Keep the food bowl accessible. Arthritis is common in senior cats and often goes unnoticed. A cat who is sore in their joints may reduce movement, including to the food bowl. Keep feeding stations at floor level and easy to reach.
Don't force diet changes too quickly. Senior cats can be creatures of habit, and a sudden switch in food can cause refusal or digestive upset. Transition over 7-10 days, mixing old and new food gradually.
Weigh your cat regularly. A small kitchen scale gives you an early warning of weight changes that are difficult to spot by sight. A loss of 10% of body weight is significant and warrants a vet visit.
When to book a vet nutrition review
Your cat has reached 10 years old and you haven't reviewed their diet recently
You've noticed weight loss, muscle wasting, or increased thirst
Your cat has been diagnosed with kidney disease, hyperthyroidism, diabetes, or dental disease
Your cat is refusing food or eating noticeably less than before
You're unsure whether a senior food is meeting their needs, or which product to choose
A vet can assess your cat's body condition score, check for underlying conditions that affect nutrition, and recommend a diet tailored to their specific health status. For cats in early kidney disease especially, the right food choice is one of the most effective interventions available.
Frequently asked questions
At what age should I switch my cat to senior food?
Most vets recommend transitioning to a senior-formulated food from around age 10, though some suggest starting as early as 7-8 for cats showing early metabolic changes. The key is to monitor body condition and adjust based on your individual cat, not just age alone.
Is wet food really better for older cats?
For most senior cats, yes. Wet food provides significantly more moisture, supporting kidney health and hydration. It's also easier to eat for cats with dental pain, which is common in older cats. If your cat has only eaten dry food, introduce wet food gradually over one to two weeks.
My senior cat is losing weight even though they're eating. What should I do?
Weight loss despite normal eating is a red flag in senior cats. It can indicate hyperthyroidism (very common in older cats), early kidney disease, diabetes, or reduced digestive efficiency. See your vet for a check-up and blood panel: catching these conditions early makes a significant difference to outcome and quality of life.
The best gift you can give a senior cat is attention to the small changes. Weight, appetite, thirst, coat quality: these quiet signals tell you a lot. Stay curious about them, and you'll be well placed to catch problems early and keep your cat comfortable and well-fed well into old age.
If you're not sure whether your senior cat's diet is right for their age and health, your vet is always the best person to ask.
