That's not the meaning of the word "natural" in the context of nutrition, from my understanding. Perhaps the word you're looking for is "traditional".

Semantics aside, I'll gladly grant you that lard is a food that has been eaten in the past. But, once again, that doesn't mean it's necessarily better than other foods that haven't been eaten in the past.

An good example is "golden" rice. An argument could be made (and has been made) that golden rice could save millions of people from devastating vitamin deficiency which they would continue suffer from were they to avoid golden rice for their "traditional" foods.

Plenty of traditional foods just aren't very nutritious or healthy.