> Side note: Why do we constantly cry about recommendations from the 1970s being different from today's recommendations?

Because hardly anything in nutrition "science" has proven to be predictive. It's all junk. Most of it intentional junk pushed by political and business interests.

For example, "Eat food, not too much, mostly plants." is just nonsense based on junk "science" funded by vegan/vegetarian aligned interest groups. I'm guessing with major multinational corporations peddling veganism, we'll get more junk nutrition science.

Considering life expectancy, health and development has increased with more meat consumption. This is true of the countries with the highest life expectancy - japan, switzerland, spain, etc.

Since we are omnivores, perhaps we should eat a variety of everything in moderation.