Editor:
In response to Hodgson’s article on Robert Lustig’s diet advice (“Obesity — How’d THAT Happen?” Jan. 22), Barry Evans defended the validity of the First “Law” of Thermodynamics (“Field Notes,” Jan. 29). We do not live in a theoretically perfect world, however, and using an incomplete description of this theorem without including losses to other energy types, such as friction, is as misleading as religious and political dogma.
Barry is interested in wastewater treatment plants, so he should be able to realize why human waste (even after the human has exercised), aka sewage, has a significant biological oxygen demand and needs to be treated to avoid polluting because of the remaining amount of “calories.” To be crude, why do some turds float?
Studies by endocrinologists and organic chemists are more reliable and consistent than the office-football-pool-type questionnaires used by many dieticians.
Charles Wilson, Orick
This article appears in 35 Days in the Forum.
Thanks Charles. The First Law (not “Law”!) takes losses into account. The human digestive tract is super-efficient–at least 95%–in wringing available energy from food, which is why human shit doesn’t make for useful fertilizer. When turds float, it’s either due to excess fat or sulfur dioxide gas (not O2), which is why farts smell like rotten eggs.
A new documentary: “Plastic Paradise, The Great Pacific Garden Patch” 2014:
http://www.hulu.com/watch/684377
determined that contamination from thermal receipts, (handed to you at the organic grocery store), is immediately absorbed into your body.
That, along with the plethora of other sources of endocrine disruptive plastic derivatives, is responsible for the hormonal problems that lead to obesity.