In the news

I hope that I’m preaching to the choir

        As you know from recent blog posts, the influenza vaccine, though it does not always prevent the flu, is important because it decreases the severity of an infection, likely avoiding hospitalization. You may also recall that an episode of influenza significantly increases the risk of a heart attack or stroke, while the vaccine has just the opposite effect. Another point to emphasize: influenza weakens the immune system, which is the reason why deaths from the flu are almost always due to secondary infection, not viral infection.

                Infectious disease experts warn that this year’s flu season will probably be more severe than most because the current strain is more potent. This is already evident in Australia and the UK. That makes getting the vaccine especially important this winter.

Lifestyle

What hardly anyone knows about exercise.

                The title of this blog might seem somewhat pretentious but the evidence is all around us. Surveys over the years are pretty consistent: about eighty percent of Americans simply do not engage in any form of exercise. An interesting coincidence: eighty present of Americans are overweight or obese. Are they the same eighty percent. Ya think?

                The human body has evolved to require several hours a day of moderately intense physical activity. Before the Industrial Age there was no way around it. Getting to or from anywhere required walking. (Lest you think that riding horseback didn’t require physical activity, be assured that a ride of any distance is a pretty good workout.) Craftsmen used only hand tools; the most mundane household chore required lifting, carrying, chopping, etc..

                Moderately intense physical activity has two major effects: it burns calories and it opens dormant blood vessels. If we use up all the calories we take in there aren’t any left to be turned into fat. That’s obvious but what is not so obvious is that those fat stores are factories (fattories?) for churning out inflammatory chemicals that are the drivers of coronary heart disease, ischemic stroke, type 2 diabetes, cancer and osteoporosis. Another interesting coincidence: none of those conditions exist in pre-industrial societies – not one, except for some cancers!

                When your heart pumps vigorously in the course of intense physical activity, every blood vessel in the body, even those that are “resting”, opens up to accommodate the flow. That ensures that every cell receives oxygen and nutrients and gets rid of accumulated waste products. The ebb and flow of blood also keeps those blood vessels flexible so that they can handle the sudden stress of the kind that might precipitate a heart attack or stroke. 

                Twenty-five percent of the blood that exits the left side of the heart goes to the head, nearly all of it to the brain. Simply put, well-fed brain cells last longer.

                The excuse that I hear most often is “I don’t have time”. I’ll address that issue in the next post.