Signs Your Pet Lacks Protein

April 26, 2025

Protein is essential for the health and well-being of pets, especially cats and dogs. Proteins, essential macronutrients, consist of amino acids, the building blocks vital for bodily functions. Protein primarily helps with muscle growth and maintenance. Active pets or those healing from injury need enough protein for tissue repair and lean muscle growth.

Additionally, protein is important for your pet’s immune support. It helps produce antibodies that protect against illnesses and infections, keeping our pets healthy and strong. A diet high in quality protein supports healthy skin and a shiny coat by supplying essential nutrients for skin cell regeneration.

Providing enough protein for your cat or dog is needed for their growth and overall health. Identifying this nutrient's importance helps pet owners make better dietary choices for their pets, resulting in happier, healthier lives.

Common Signs of Protein Deficiency

Protein is important for your pet’s health, helping build muscles, maintain a shiny coat, and support the immune system. Pets with not enough protein in their diet may display different signs, ranging from subtle to obvious. Here are some of the most common symptoms to watch out for:

Dull, dry, or thinning coat
Muscle loss or weakness
Lethargy or low energy levels
Slow wound healing
Weight loss despite a normal appetite
Increased susceptibility to illness
Brittle nails or dry skin

Consult your vet if your pet shows any of these signs. Early intervention and a protein-rich diet can significantly impact recovery and well-being.

Behavioural Changes to Watch Out For

Signs of protein deficiency can also appear in your pet's behaviour, not just physically. If your usually energetic dog appears withdrawn or your curious cat is suddenly disinterested in play, it could be more than just a mood. Behavioural changes are often missed, yet they can be early signs that your pet's diet is off.

Here are some behaviour shifts to keep an eye on:

Lack of interest in play or exercise

Your pet may seem unusually lazy, avoid their favourite toys, or show little excitement for walks.

Increased irritability or restlessness

Low protein can affect mood, making pets more agitated or harder to settle.

Excessive sleeping or low responsiveness

They might sleep more than usual or take longer to respond when called.

Avoidance of interaction

Some pets may withdraw from family members or avoid physical contact.

Anxiety or nervous behaviours

A drop in protein can affect brain function and lead to nervous habits like pacing or whining.

Changes in behaviour may be mistaken for ageing or laziness, but when combined with other symptoms, they might indicate a more serious problem. Trust your instincts if something feels “off.” Check with your vet and review your pet’s diet for any protein gaps.

Who’s Most at Risk?

Any pet can experience protein deficiency, but some are more at risk based on their life stage, health, or lifestyle. Identifying high-risk pets allows you to take early action to safeguard their health and avoid long-term problems.

Here are the groups that need extra attention:

Puppies and Kittens

Growing animals need more protein to support rapid development of muscles, organs, and tissues. A lack of protein during this stage can lead to stunted growth and poor immune function.

Pregnant and Nursing Pets

Mothers need significantly more protein to support their health and the development of their offspring. Deficiency during this period can lead to weakness, poor milk production, and undernourished litters.

Senior Pets

As pets age, their ability to absorb and process nutrients declines. Without enough protein, they may experience muscle loss, lowered immunity, and increased fatigue.

Active or Working Breeds

Dogs with high energy levels—like working dogs, sporting breeds, or those with active lifestyles—burn more calories and require more protein to maintain muscle strength and stamina.

Pets Recovering from Illness or Surgery

Healing bodies need extra protein to repair tissues and fight off infections. Without it, recovery can be slower and more complicated.

Make sure your pet's diet has enough high-quality protein if they fall into these categories. Consult your vet and explore foods designed for your pet’s life stage, such as Pro Plan at Petso, which caters to pets at every stage of their journey.

What You Can Do About It

As a pet owner, you can do much to support your pet’s health, particularly in preventing protein deficiency. Here are some easy, practical steps:

Visit the Vet Regularly

Regular check-ups reveal early signs of nutritional deficiencies. If your pet shows fatigue, weight loss, or a dull coat, visit the vet.

Select a nutritious, protein-packed diet

Pet foods vary in quality. Seek reliable formulas that provide complete and balanced nutrition, particularly those high in quality animal protein.

Stay Active Together

Regular exercise keeps your pet healthy and alert. Activities like fetch, brisk walks, and puzzle games help maintain muscle tone and support a healthy weight.

Keep Their Minds Engaged

Mental stimulation is as crucial as physical activity. Utilise toys, puzzles, or games to reduce boredom and anxiety.

Grooming Matters More Than You Think

A dull coat may indicate inadequate nutrition. Brushing, bathing, and grooming help you notice early changes in your pet's skin and fur.

Don’t Let Low Protein Sneak Up on Your Pet

Protein deficiency may not be the first concern when your pet appears unwell, but it can lead to serious issues if ignored. Signs like a dull coat, weak muscles, and changes in behaviour or energy levels can be easy to overlook. Once you notice them, it's time to take action.

Providing your pet with a balanced, protein-rich diet is one of the best ways to support their overall health and happiness.

🐾 Not sure where to start? Explore the Pro Plan at Petso—backed by science and trusted by vets to deliver the nutrients your pet truly needs.

Because when your pet feels good, life’s just better—for both of you.

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