Re: How do the nutrients in our foods get into our bloodstream?

Aloha, Ben,

     My apologies for being so tardy in getting this answer out to you.  
We have just started the Spring semester here at the University of 
Hawai`i/Manoa, where I am an Associate Professor on the Human Nutriton, 
Food, and Animal Sciences Department faculty...just plain 'zooey' time, 
all the way around.
     Now, to your very interesting question...and one, the answer to 
which, is actually part of several lectures that I give every semester to 
my introductory nutrition students.  Your author is a bit off from what 
science believes happens (and which is quite easy to prove, with the 
appropriate types of research studies).  But, first, I need to provide a 
bit of background information about nutrients, since part of the answer is 
a bit correct.
     There are six major types of nutrients:  carbohydrates (CHO), lipids 
(FAT), protein (PRO), vitamins (V), minerals (M) and water (H2O).  
     The CHOs are eventually digested (broken down) inside of the 
digestive tract (outside of the body, really!), mostly into simple sugars, 
mainly glucose.  Glucose is absorbed across the lining of the digestive 
tract through the cells of the small intestine, directly into the blood 
stream.  This transport is linked to the transport of sodium ions (where 
is where the author may have gotten his ideas), but the process is done by 
what is called 'active transport'...that means that energy needs to be put 
into the system for the transport to occur.  There is really 
nothing 'electrical' or 'magnetic' about the process.
     The PROs are eventually digested in the same place into individual 
amino acids.  These amino acids are also actively transported through the 
cells that line the small intestine, into the blood stream.
     The FATs are a very complicated story.  Suffice it to say that the 
breakdown products of fats (called fatty acids, monoglyderides, 
diglycerides, and glycerol) are all fat-soluble products (not like the 
amino acids and glucose, which are water-soluble).  Thus they must be 
specially packaged and specially carried across the cells lining the small 
intestine and into a special fluid, called the lymph (in lymph vessels 
just inside the lining of the digestive tract.  The way that the fatty 
substances are packaged make them able to travel via the lymph, and 
eventually into the blood stream, through two large lymph ducts right 
under your collar bones.
     The minerals are absorbed mainly into the blood stream, just like the 
amino acids and glucose.  The vitamins go either into the blood stream 
(the water-soluble ones) or into the lymph (the fat-soluble ones).
     Other than the 'use' of the sodium ions to co-transport either 
glucose or the amino acids, I'm not sure where the author got the 
incorrect idea that electrical or magnetic attraction is how they get 
absorbed.  I wonder if the author was trying to sell some electrical or 
magnetic paraphenalia or supplements along with the bad information?
     Your best bet for good, sound nutrition information is to get access 
to a nutrition text that is being used in an introductory university 
nutrition course, near you.  We use Warldaw's Contempory Nutrition: Issues 
and Insights, 5th edition.  There is a great chapter (Chapter 3) 
that 'tells it like it is.'  The other piece of advice that I might give 
you is to contact the nearest dietitian, if you want good information 
about nutrition.  You can locate one via the American Dietetics 
Association web-site ().  A dietitian is 
nutrition professional who has at least a BS degree in nutrition and has 
completed a post-graduate internship and who has passed a national exam 
administered by the American Dietetics Association. Good luck on learning 
more about nutrition and how it works in your body.