This picture, taken at a California Costco, shows the vast difference in color between wild-caught salmon on the left and farmed salmon on the right.

The Spartan Diet calls for only wild animal protein, which includes venison, elk, moose, bison, alligator, ostrich, antelope, dove, pheasant, quail, duck, rabbit, boar, wild turkey, goose and others. Nowadays it's easy, though not inexpensive, to find such meats online and have them delivered with ice packs to your door.

But the other major and easier-to-find type of wild animal meat is fish. The only canned food on the Spartan Diet, for example, are sardines, which are such a low-cost and high quality protein source that we encourage people to eat canned sardines for convenience, cost or for other reasons.

When buying fish at the market, or ordering fish at a restaurant, always insist on wild-caught fish over farmed fish. Farmed fish are fed an unhealthy, unnatural diet and are confined in filthy conditions.

One of the healthiest options is wild-caught salmon, which is more expensive than farmed salmon. However, the Spartan Diet calls for always buying wild fish. You can see in this picture the vast different in color between the healthy, natural wild salmon and the factory-farmed salmon, which is pale and indicates sick animals.

On the Spartan Diet, portions of meat and fish are smaller and its eaten less frequently. So the total amount spent on animal protein is about the same.

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