Grit Happens: Why Stones Are the Secret to Healthy, Happy Chooks

Most chicken keepers have heard the word grit, but here’s where it all goes off the rails. Nine times out of ten, people think grit means shell grit — those chalky bits of oyster shell you toss in for stronger eggs. Useful? Absolutely. But it won’t stop your hen from choking on a clump of grass, and it sure won’t help her digest that handful of scratch grain you just threw out.

The real secret weapon is something completely different: digestive grit. Not calcium, not a supplement — just good old-fashioned hard stones. It’s the missing piece in most backyard flocks, and without it, your birds are basically trying to chew steak with no teeth.
 

Two Grits, Two Jobs

Here’s where most keepers get tripped up: grit isn’t just one thing.

Shell grit, oyster shell, limestone — they all fall into the soluble grit camp. These dissolve in the digestive tract, topping up calcium reserves so hens can pump out strong eggshells. Essential for layers? Absolutely. But let’s be clear: this kind of grit doesn’t grind a single grain.

Then there’s digestive grit — the lesser-known grit. It’s insoluble, made from tough little stones like granite or flint, and it doesn’t dissolve away overnight. Instead, it parks itself in the gizzard and works like a set of internal millstones, crushing and tearing food apart so your birds can actually digest what they eat.

The problem is that too many backyard keepers think shell grit and digestive grit are the same thing. They’re not. One is calcium, the other is chewing power. Skip the lesser-known grit, and your birds are left without the “teeth” they need to handle grass, grains and everything else they peck up.
 

Birds Know Best - Grit in the Wild

You don’t need a lab coat to see how important grit is. Just look at wild birds.

Ever noticed pigeons, doves or sparrows on gravel driveways, roadsides, or garden beds? They’re not just looking for seeds and insects - they’re swallowing stones. Every bird in nature, from tiny finches to emus, instinctively seeks out grit to keep their digestive system running smoothly.

The difference is that wild birds have constant access to it. They spend all day foraging across different terrains and naturally top up their supply. Backyard chickens, on the other hand, are often confined to soft ground, lawns or bark chips where stones are scarce. Unless your chooks are free-ranging on rocky soil, they simply won’t find enough grit to keep their gizzards in working order.

And when the gizzard doesn’t grind efficiently, everything else in the digestive system works less efficiently too.
 

The Science Bit: The Mighty Gizzard

A chicken starts by choosing what to peck at, then swallows it whole — no chewing involved. The food first collects in the crop, a storage pouch at the base of the neck, before moving into the proventriculus (the “true stomach”), where it’s mixed with digestive enzymes and acids. From there, it enters the gizzard — the bird’s internal grinder. This muscular organ contracts powerfully, and when grit is present, it works like a mortar and pestle: crushing grains, shredding grass, and grinding scraps into a fine paste ready for absorption further down the digestive tract.

Without grit, fibrous material and coarse feed aren’t broken down properly. They sit half-digested, fermentation takes over, and suddenly you’re facing problems like sour crop or impaction. Even with processed pellets, grit makes digestion more efficient by improving nutrient release and keeping everything moving as it should.
 

Health & Welfare: Stronger Birds, Happier Keepers

Still not convinced? Here’s what happens when your flock has access to grit:

• Fewer crop problems – grit breaks up long grass and stubborn feed before it could potentially cause blockages.

• Better motility – digestion flows naturally, no sitting heavy, no sluggish gut.

• Improved nutrient absorption – more bang for your buck from every grain or pellet.

• Firmer droppings – better digestion of food through a properly working gizzard means firmer poo.

• Healthier body condition – birds maintain weight more easily and put less stress on their systems.

• Stronger gizzards – grit stimulates the gizzard to grow larger and more muscular, giving your chooks the digestive “engine” they need.
   

The Economics: Small Stones, Big Savings

Feed is your biggest cost in poultry keeping. Studies show that giving chickens grit improves feed conversion by 7–10%. In plain English, your birds put on more weight or lay more eggs while eating less.

Think about that in backyard terms: fewer wasted pellets, healthier hens, and eggs that practically pay for themselves. All from a handful of stones.
 

Practical Tips for Using Grit

Here’s how to make grit part of your flock’s routine:

• Chicks (0–6 weeks): Too young to tell grit from grain. Mix a tiny amount of clean river sand into their feed (about 1–2%). They’ll find it naturally without gorging.

• From 6 weeks onward: Offer grit free-choice by placing it in a small container or scattering it in their run. Scratching through it mimics natural foraging and keeps them occupied, satisfying their instinct to search and peck.

• Layers: Keep offering shell grit as well — remember, calcium for shells, grit for grinding. Different tools for different jobs.

The beauty of grit is that chickens self-regulate. They’ll take what they need, when they need it.
 

The Final Peck

So here’s the bottom line:

• Shell grit = calcium.

• Digestive grit = teeth.

• Your chooks need both.

Without digestive grit, you’re asking your birds to live on a diet they can’t properly process. With it, you’re giving them the tools nature intended — better digestion, fewer problems, more efficient feeding, and healthier, happier chooks.

Grit happens. Make sure it happens in your backyard.