Should Your Dog Eat a Grain-Free Diet? What Pet Owners Need to Know

A veterinarian-guided look at grain-free dog food, nutrition, and heart health

At Willowbrook, we understand that pet owners want to make the healthiest, most informed decisions for their dogs. Over the past decade, grain-free dog diets have surged in popularity, often marketed as a more “natural,” cleaner, or higher-quality feeding option. But despite appealing packaging and bold claims, grain-free diets aren’t always the well-balanced nutritional choice they seem to be—and in some cases, they may pose risks to your dog’s health.

Here’s what you should know before choosing a grain-free diet for your dog.

“Grain-Free” Is Marketing, Not Medicine

There is no scientific evidence showing that grain-free diets offer nutritional advantages over traditional grain-inclusive dog foods.

Healthy whole grains - such as rice, barley, and oats - are:

  • Safe for dogs
  • Highly digestible
  • Rich in fiber
  • Sources of essential nutrients and amino acids

Many grain-free diets simply swap grains for alternative carbohydrates like potatoes or legumes. These substitutions don’t automatically improve digestibility or nutritional quality, and they can sometimes alter the diet in ways that affect your dog’s health.

Taurine Deficiency and Your Dog’s Heart

Whole grains help supply amino acids, including taurine and taurine precursors that support normal heart function. Some grain-free diets rely heavily on legumes or exotic ingredients, which may reduce taurine availability.

Low taurine levels can contribute to dilated cardiomyopathy (DCM)—a condition that affects the heart’s ability to pump blood effectively. While not all cases of DCM are diet-related, nutrition plays an important role in a dog’s heart health.

Understanding Nutritional-Related Dilated Cardiomyopathy (nr-DCM)

In recent years, the FDA has investigated a potential link between grain-free diets and DCM in dogs. Although the relationship is not fully confirmed, many reported cases of nr-DCM involved dogs eating grain-free diets—particularly those rich in:

  • Peas
  • Lentils
  • Chickpeas
  • Other legumes or “pulse” ingredients

This does not mean all grain-free diets are harmful. Instead, it highlights that:

  • Ingredient balance matters
  • Formulation matters
  • Marketing claims do not guarantee nutritional safety

Choosing dog food should always be about complete nutrition—not the presence or absence of grains.

How to Choose a Complete & Balanced Dog Food

Instead of focusing on the term “grain-free,” look for diets that meet strong nutritional standards. High-quality dog foods should be:

  • AAFCO-certified as “complete and balanced”
  • Formulated using feeding trials or advanced nutritional research
  • Produced by companies with veterinary nutritionists on staff
  • Transparent about ingredient sourcing and quality control

A well-formulated grain-inclusive dog food remains one of the most reliable ways to ensure your dog receives all essential nutrients.

Speak With Your Veterinarian Before Choosing a Grain-Free Diet

Most dogs do not need grain-free food. However, certain medical conditions may require specialized diets, and your veterinarian can help determine whether a grain-free formula is appropriate - or whether a different high-quality option would better support your dog’s health.

A veterinary consultation ensures that your dog’s nutrition is based on science, not marketing trends.

The Bottom Line

Grain-free diets may sound appealing, but they are not automatically healthier—and in some cases, they may increase the risk of nutritional imbalances or heart concerns.

If you have questions about your dog’s diet or need help choosing a safe, balanced, and appropriate food, Willowbrook Veterinary Hospital is here to guide you with evidence-based recommendations that support your dog’s long-term health and well-being.