This blog is intended to go along with Population: An Introduction to Concepts and Issues, by John R. Weeks, published by Cengage Learning. The latest edition is the 13th (it will be out in January 2020), but this blog is meant to complement any edition of the book by showing the way in which demographic issues are regularly in the news.

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Wednesday, December 11, 2013

Health and Planetary Benefits of a Plant-Based Diet

As the world's population heads toward 9-10 billion by the middle of this century, the issue of feeding everyone becomes ever more important. At the moment, we are not only increasing numerically, we are increasing our per capita meat consumption. This means that we raise an ever greater number of animals for slaughter. Forgetting for the moment the ethical issues associated with that, there are two key problems: (1) feeding them takes food directly off the human table and very inefficiently reroutes it through animals; and (2) too much meat is not healthy. This latter concern may be why we are getting sicker over time, even as life expectancy goes up.

There is a popular conception (misconception, really) that eating meat is a sign of wealth and well-being. In fact, the evidence suggests that a largely plant-based diet is better for you, and a paper just published online today in Nature, led by a team of researchers at Harvard, emphasizes the incredible ability of the human gut to adapt quickly to different diets:
In concert, these results demonstrate that the gut microbiome can rapidly respond to altered diet, potentially facilitating the diversity of human dietary lifestyles.
The point is that your body adjusts rapidly to your diet, so moving from an animal-based diet to a plant-based diet is not a huge adjustment, as far as your gut is concerned. That story has a link to another recently published article from researchers in Australia suggesting that people were generally aware of the health benefits of a plant-based diet. The younger and better educated you are, the more likely you are to share this view of the world. I find that to be very encouraging for the future. Another encouraging development is a recently published book by Vaclav Smil, one of the world's foremost authorities on the world's food supply. His book is titled: "Should We Eat Meat? Evolution and Consequences of Modern Carnivory." Here's a snippet from his website about the book:
The heart of the book addresses the consequences of the “massive carnivory” of western diets, looking at the inefficiencies of production and at the huge impacts on land, water, and the atmosphere. Health impacts are also covered, both positive and negative. In conclusion, the author looks forward at his vision of “rational meat eating”, where environmental and health impacts are reduced, animals are treated more humanely, and alternative sources of protein make a higher contribution.

1 comment:

  1. “I'm thinking about that diet where you fast two days a week and eat whatever you like the other five. ... In this article, I'll uncover the good, the bad and the ugly on the 5:2 ..... This can lead to people thinking they're so restricted on their fast .... But as long as the scale shows dropping weight, I'm doing fine. winifreda