When you are at a store looking at colorful packages and debating what bag of food to buy for your pet, don't be fooled by the front page advertising. Words like "Natural", "Holistic", etc. are just words till you match their meaning to the actual content of the bag.
Every bag of pet food must have an ingredient list and nutrition analysis. This information is also available at a manufacturer's website. In order to make the package attractive and sellable, manufacturers often put only a fraction of the truth on the front of the bag. Say, majority of supplements (like vitamins and minerals) are chemically synthesized and added to the pet foods, but “all natural” statement is allowed to be put on the front.
Read the ingredient panel, not the front to get an idea how natural the ingredients are.
Another issue is what is called natural food for a particular animal.
Corn is natural. No one will argue with the statement. It has roots, grow from soil as any other plant. Yet, it is inappropriate to feed it to a cow, much less to a dog. Corn has never been a part of natural diet for these mammals, and probably will never be. Cows are herbivores; their natural diet is grass, not grains. Dogs are carnivores, meat eaters.
Corn and wheat also contain gluten that often is linked to severe allergies on pets with symptoms like excessive shedding, itching, scratching, ear infections, hot spots, fatty cystic deposits under the skin, and obesity.
Rice is natural, soy, potatoes and peas are too. Yet these plants are on higher glycemic scale. Meaning carbohydrates in these plants break down to sugars fast, and cause surges of high glucose in the blood stream. Pancreas releases insulin to offset these spikes, and in prolonged period of time such unstable glucose levels in the system eventually cause diabetes.
Diabetes and other diet related conditions are unknown in wild carnivorous animals - they do not eat potatoes, rice or peas. Plants and roots are not a part of their natural diet.
Natural foods still can contain chemicals, dyes, flavor enhancers and other unnatural ingredients. Including toxic fish meal preservatives like ethoxyquin. It does not have to be listed on a label as many manufacturers buy fish meal preserved with ethoxyquin from someone else. Since the final product ingredient list does not require full list of sub-ingredients, such toxic ingredients make their sneaky way into the final product.
Will you take a moment and read your pet's food ingredient list?