Did you know you have a “brush border” that keeps you alive?
The brush border is the little fingerlings that line your small intestine and absorb nutrients from the food you eat. It is only one cell thick. Think about that. There’s one cell between the food you eat (mixed with stomach acid into chyme) and your blood supply. Intestines are gloriously efficient. Yep, they were designed for a time when we needed every bit of nutrition from our food. I’m captivated by the brush border for a couple reasons:
1) I love alliteration.
2) it’s a great descriptor using simple words.
3) there seems to be a paradox in the fact that our efficient mechanisms make us obese, since obesity is so inefficient.
4) Celiac disease (gluten intolerance) wrecks the brush border by taking the tips of those fingerlings.
5) the brush border can repair itself, even after gluten has damaged it.
6) who is the brush border in the Body of Christ?
These notes are from Tues night when we heard the second of two lectures on Gastrointestinal Physiology at the Mini-Medical School. Lecture by Dr. Susan Mulroney, who was full of passion for her topic. Great presenter.
Also worth remembering and future ponderment:
~ Appetite is controlled by balance of ghrelin (blood protein) and leptin (produced in adipose tissue).
~ There is a fun way to determine how big your pyloric sphincter is.
~ The interplay of internal and external anal sphincters explains a lot! “Having a colon is what makes us a social animal.”
~ Everything we eat is absorbed via the portal vein into the liver. “Love your liver.”
~ Carbohydrate moves through the system much more quickly than fat.
~ There are 1.5 liters of saliva in your body. “You have not appreciated your saliva, I’ll tell you that right now.” Morning breath is caused by the overnight decrease in saliva production which allows bacteria to proliferate in the mouth.
~ Fun word: borborygmi = intestinal sounds of fluid shifting (“stomach gurgles”)
~ Stomach accommodation. You don’t feel pressure in your stomach until you’ve eaten a liter of food. (holy-moley) ?Cool pictures of how bariatric surgery works. It makes me wince.
~ Stomach acid is as acidic as battery acid. Yet the chyme in the first part of your small intestine is neutral. How amazing is that?
~ Cells along the GI tract are constantly dying and being replaced. These slough off into your poop. So the fat in your poop is not from dietary fat but from your cells. This means all the fat gets broken down and used by your body, and it is usually full of toxins, etc, it is far from a neutral substance.
~ Bilirubin is what makes your urine yellow. Bilirubin is the result of red blood cell degradation, and if the body doesn’t excrete it properly it builds up in the body and causes jaundice (yellowed eyes and skin).
~ The pancreas has two functions: secreting buffers into the small intestine, and releasing insulin etc into the blood. Buffers are wicked important.
~ The gall bladder is on the right side of the body. It’s an empty sac. Well, if it’s not empty it’s full of gallstones which is B A D.
~ Fun word: haustrae = the bundles of chyme and feces in the colon, those bulges that get pushed by segmental propulsion through the colon.
~ 30% of feces is bacteria. (hoo-boy, that explains things too!)
~ Diarrhea is caused by anything that irritates your intestinal lining. (makes sense — quick, let’s move it through)
~ Fun word: ileum = the last part of the small intestine, before emptying into the colon.
~ fecal transplants might actually work — to replenish the “healthy” bacteria so they can proliferate and aid in digestion — they take poop from a healthy family member — okay, do I need to tease out the possible applications to church life?
~ I had eaten black beans with my dinner just before this lecture which provided me with some internal merriment.
“So eat drink and be merry.” (insert appropriate quote from Ecclesiastes!)