The scores
Diamond Naturals Adult Chicken & Rice: B (78/100) — Above average. Chicken and chicken meal lead, backed by quality whole grains, probiotics, and superfoods.
4Health Adult Salmon & Potato Grain-Free: C (70/100) — Decent. Salmon and salmon meal up front provide solid protein, but the formula lacks depth beyond that.
How the ingredients compare
The top five ingredients tell the story:
Diamond Naturals: Chicken, Chicken Meal, Whole Grain Brown Rice, Cracked Pearled Barley, White Rice
4Health: Salmon, Salmon Meal, Potatoes, Peas, Potato Starch
Both brands open with two named animal proteins — a strong start either way. The difference shows up in what comes after. Diamond Naturals fills positions three through five with whole grains that provide fiber, B vitamins, and slow-release energy. 4Health fills those same slots with potatoes, peas, and potato starch — essentially the same starchy carbohydrate appearing twice under different names, a tactic that spreads out starch content so no single entry looks too dominant.
But the real gap isn't in the top five. It's in the supporting ingredients. Diamond Naturals includes chicory root prebiotics, kale, blueberries, chia seed, coconut, flaxseed, and fish meal. 4Health includes none of those. No named fruits, no named vegetables, no prebiotics, no probiotics. That's where the 8-point gap comes from.
Where Diamond Naturals pulls ahead
Nutritional depth: Diamond Naturals has a supplement package that belongs on a food costing twice as much. Chicory root extract provides prebiotic fiber for gut health. Kale, blueberries, chia seed, and coconut add superfood antioxidants. Both flaxseed and fish meal deliver plant-based and marine-based omega-3s. 4Health has flaxseed and fish oil for omega-3s, but nothing in the prebiotic, probiotic, or superfood categories.
Grain quality: Whole grain brown rice and cracked pearled barley are nutrient-dense, slow-digesting carbohydrates. 4Health's potato and potato starch combination is a simpler, less nutritious energy source — and as a grain-free formula, 4Health falls into the ongoing FDA investigation into a potential link between grain-free diets and DCM in dogs.
Value: Diamond Naturals typically costs the same or less than 4Health per pound. Getting B-grade ingredients at the same price as a C-grade formula is the kind of value gap that makes this comparison straightforward. Shop on Amazon →
Where 4Health holds its own
4Health's double salmon foundation is genuinely strong. Whole salmon and salmon meal provide quality fish-based protein with naturally occurring omega-3 fatty acids. If your dog does better on fish than poultry, 4Health offers a protein source that Diamond Naturals' chicken-based formula doesn't.
The taurine addition is a thoughtful inclusion, particularly for a grain-free formula where taurine deficiency has been a concern. And natural preservatives (mixed tocopherols) match Diamond Naturals on that front — neither brand uses artificial preservatives like BHA or BHT.
4Health is also a Tractor Supply exclusive, which makes it convenient if that's already where you shop. Diamond Naturals has wider distribution but isn't carried everywhere. Shop on Amazon →
The bottom line
Diamond Naturals is the better food here, and the gap is meaningful — a full letter grade from C to B. Both brands target the same budget-conscious buyer, but Diamond Naturals delivers probiotics, superfoods, quality whole grains, and dual omega-3 sources that 4Health skips entirely. 4Health is a decent store-brand option with solid fish protein, but it's missing the nutritional extras that separate good food from genuinely good food.
If your dog needs a fish-based protein source, 4Health is a reasonable choice. For everything else, Diamond Naturals offers more nutrition for your dollar. Read our full reviews of 4Health and Diamond Naturals for the complete breakdown.