The Health of the Earth

My daughter completed a degree in culinary arts, and a big part of that degree is learning to be a chef.  When I watch her cook I notice that foods tend to be heavily salted, more than we would normally do.  Of course, it has to be sea salt because the flavor is better to a trained tongue.  The focus of culinary arts cooking is taste and appearance.  Everything else is secondary, including health.

There is a Biblical metaphor "salt of the earth," in reference to something bringing joy, hope, and encouragement to life, in the same way that salt could add excitement and enhance the pleasure of food.  The expression was born at a time when 99.99% of people ate very plain food, with none of what we call additives, and most people lived day to day, right on the edge of hunger.  Their challenge would have been getting enough calories and protein, not cutting down on fat, salt and sugar.

Today we have this thing called health: it ruins everythinig!  It used to be said "Eat, drink, and be merry for tomorrow we die."  Now it is eat healthier today so you will live to the next day or the day after that.  All of this is hyperbole, of course, but there is a grain of truth.  Health promotion often tries to get people to do things that are not, at least at first, pleasant.  Exercise is an example.  Other times we try to get people to stop doing things that they enjoy, like eating too much salt.

Earlier this year, the U.S. Institute of Medicine issued a call for Americans to decrease their salt consumption.  It seems that almost one third of adults have clinical high blood pressure (HBP), while 20% of those with HBP don't know it.  Prevalence increases with age, so that by the time we are 65, about 2/3 of us have HBP.  What does this have to do with salt?

A number of years ago, one of my students analyzed data from what is called the National Health and Nutrition Examination Survey.  This is a national collection of data on the health and diets of a large sample of Americans.  My student found that those who ate a lot of salt were no more likely to have HBP than people who ate moderate or small amounts.  In other words, salt was not a primary cause of HBP.  So why is the IOM trying to decrease salt for everyone?

While salt in the diet may not be a primary cause of HBP, it certainly elevates blood pressure among people who have the disease of HBP.  For people with this illness, salt in the diet leads to increased salt in the blood stream.  A high concentration of blood sodium promotes osmosis of fluids from surrounding tissues into the blood.  More fluid increases pressure inside the arteries.  HBP is an important risk factor for heart attacks, strokes, kidney failure, and blindness - all serious threats to life and health.

The IOM wants to decrease salt for all Americans because 1) HBP is extremely common and extremely serious; 2) low salt diets would benefit those who go for months and years not knowing they have HBP; 3) when someone with a new diagnosis of HBP is asked to eat a low salt diet, it is a difficult and radical change for most people.  If we could all get used to less salt, dietary change would be much easier for the third of us who will develop HBP.  The challenge is to work with the food industry and human motivation to wean ourselves from high sodium diets.

A lot of times, health promotion advice is received as bad news.  Our challenge is for health to be salt of the earth: a desired way to life.