Jaws: The Story of a Hidden Epidemic

Jaws: The Story of a Hidden Epidemic by Sandra Kahn and Paul R. Erhlich

People's jaws are not healthy these days. Food is soft, so we don't have to chew as much. Babies are weaned too early to soft food. People breathe with their mouth instead of their nose. This jaw health causes problems sleeping and breathing as well as other health issues. The authors propose the solution that involves their brand of orthodontic surgery to fix it. they also propose that we do simple things like chew more and breathe through our noses instead of mouths. There seems to be some reasonable items in here along with other bits that appear fairly self-serving.

Breath: The New Science of a Lost Art

Breath explores the limited modern science of modern breathing as well as the extensive cultural traditions and practices relating to breathing. There are tales of modern medical practices that have helped aid multiple ailments through breathing practices. The scientific explanations for some breathing practices can be quite interesting. 

Early in the book, the author recounts his experience in a Stanford study. At the start, he could only breathe through his mouth. Then he could breathe through his nose. Restricting to just mouth breathing caused all sorts of negative health outcomes (such as high blood pressure and snoring) Nsala breathing helped fix these problems. The author also describes some healthy native cultures that tried to encourage everyone to breathe through the nose.

There has been a distinctive change in skulls and mouths since the industrial revolution. This is said to be related to the processed food. We just don't need to exercise our mouths like we used to. The highly processed soft food does not require us to chew very much. This leads to a reshaping of our mouth and crooked teeth. This also can cause problems with breathing.

Many ancient religions and cultures have religious practices that encourage varied breathing regimes. 5.5 seconds in, 5.5 seconds out for 5.5 breaths per minute seems to be a good pattern. This slow breathing helps to improve health. There were also anecdotes given of athletes that helped improve performance by limiting breathing. (This was something similar to "high altitude" training performed at low altitudes.) Our lungs and diaphragm can be exercised. We also tend to have a surplus, with only a fraction of the air breathed in actually being used.  Carbon Dioxide is also posited to have a significant role in health. Some people have focussed on looking at CO2's role. Breathing in pure CO2 can also stimulate fear responses. 

The book has some simple breathing exercises that can be done (such as breathing through the nose as well as slow breathing.) It also discusses some of the more advanced breathing regimens that require professional assistance. Breathing has been anecdotally shown to improve outcomes for various conditions, however, it is not a cure-all for everything.