I'm a pastured pork farmer, so I'm biased.
First, consider my USDA tables in the back of Mark Shephards "
Restoration Agriculture" indicate that comparing lamb,
beef, pork and
chicken, (in terms of vitamins, minerals, balanced proteins, fatty acids etc) Pork was at the top of the most categories, beef and lamb were together, and
chicken far behind.
2 problems: this is national statistics based on conventionally produced meats; and this deals with the positives, not the negatives.
Many of us are privileged to consume the meat we grow, so we don't have to go by gick-fed animals with impending liver failure.
The food chain is also a nutrition chain. Both toxins and nutrients condense up the food chain, and are usually stored in the liver and fat. This is why predator fish (like salmon) are more likely culprits of mercury poison, but better sources of Vitamin D.
Pigs are further up the food chain, and therefore more dangerous/potentially better than herbivores.
Pig diets, and thus pig flesh are more similar to ours. More caution is probably necessary in terms of cooking both for parasites and smaller bugs, although a healthy animal is a healthy animal.
Then the other mantra: pigs are wasteful and environmentally unfriendly? I believe they have a place in the ecosystem, and that harvestable calories is not the only measure of
land unit. My pigs
root through many acres of woods, but realistically get maybe 75% of their diet from supplements.
I'd say pigs have 2 roles: forest revitalizer/grazer and (for humans) waste disposal. My pigs feast on microbrewery spent brewing grains and commercial cherry byproduct as well as corn based grain mixes.
Nutrition in -> digestive magic/nutrition increases -> nutritive
poop and nutritive stored (meat). . This is why we don't rush our animals too early: older animals accumulate more nutrients.
I believe pork
can be very healthy