Many critics promote swapping seed oils for animal fats like butter, beef tallow and lard. Just two decades after the fat-free era of the early 2000s, people are now fighting about which fat is best.

The glorification of animal fat is a convoluted mix of politics, populism and wistful fondness for a disease-free past. Except we weren’t healthier in the past.

Nathan Coleman has more. Grey seals are born in late December and January when they are quite scrawny and have almost no fat stores. How, then, do they manage to survive in such frigid temperatures?

Another contributing factor to lard's declining popularity and use is the health associations with it. Typically, foods like lard, butter ghee are high in saturated fats, which is common with animal ...