Tuesday, June 25, 2013

Certifiably Sweet

This announcement that has been a long time coming.....

I GOT CERTIFIED! I passed my test yesterday and I could not be more excited!

I was a little worried about the test given my schedule the past few weeks... but I had nothing to worry about. I studied hard and I was prepared. :)

There was no way I could have done this without my amazing support system of family and friends. Thank you all for what you've done for me.

...and now for something completely different. :) SUGAR!

Yes, this was my Halloween costume from 2 years ago. Yes, I personified a sugar rush.
Yes, those are Nerds glued to my face. Yes, I did go to a bar dressed like this. :)

Who among us doesn't get a little happy for the day after Halloween, Easter, or V-Day for the sweet deals on candy? (see what I did there??) Now that I've gotten your attention with a really dumb joke... here's some science!

There are three types of sugar; monosaccharides, disaccharides, and polysaccharides. Monosaccharides are single-unit sugars like fructose, glucose, and galactose. Disaccharides are double-unit sugars like maltose, sucrose (table sugar), and lactose (milk sugar). Maltose is made up of two glucose units, sucrose is made up of a fructose unit and a glucose unit, and lactose is made up of a glucose unit and a galactose unit. Polysaccharides are glycogen (stored glucose in animals), starch, and fiber (both digestible and indigestible). Yes, starch and fiber are technically sugars.

Incidentally, lactose intolerance is a condition suffered by many people who cannot make lactase which separates the bond between the glucose and galactose in milk sugar. No lactase means no digesting of the lactose sugar which causes the indigestion symptoms.

Random fact: greek yogurt has less lactose then other yogurts, some people (like myself) who are mildly lactose intolerant can eat greek yogurt with no digestion issues. As if you needed another reason to love the stuff.

So, how does your body process this stuff?

The nutrients are absorbed by the "brush border" in your intestine and only single molecules can be moved across and into the blood stream. You might wonder how your body handles those disaccharides and polysaccharides. Remember how I briefly mentioned lactase? That's an enzyme. Its sole purpose is to split the lactose molecule into it's respective glucose and galactose molecules. Maltase splits the maltose sugar and sucrase splits the sucrose sugar. Once these are split, they're ok to be digested. Polysaccharides, like starch, are "processed" by other juices in your digestive tract (mmmmmm, I'll put myself off my breakfast yet*), specifically by an acid called chyme which is released into your small intestine by the pancreas and broken into disaccharides for further digestion in the intestine.

There are some sugars (carbs) that are completely indigestible. Those are called insoluble fibers. Your body simply does not have the enzymes required to break these down. Since your body isn't digesting these products... and this is the part that I still have trouble wrapping my mind around... you don't get any energy from these fibers. Is that not insanely weird????!?

But I digress...

The spirit of the question someone asked me was if the human body absorbed the different sugars in different ways. The answer appears to be yes, but I don't know enough to explain why in my own words. I'm also not qualified to be talking that kind of science talk. So here are some words by other people on the subject.

A paper by Purnell et. al. titled "Brain functional magnetic resonance imaging response to glucose and fructose infusions in humans", which essentially means "hey guys, we photographed a human brain with an MRI machine after feeding the subject two different types of sugar, pay us to see the results!" If you have access to things like that, click the link above to view the actual paper.

Now, I can only see the abstract of this article which states:

Methods: Nine healthy, normal weight subjects underwent blood oxygenation level dependent (BOLD) fMRI measurements during either intravenous (IV) glucose (0.3 mg/kg), fructose (0.3 mg/kg) or saline, administered over 2 min in a randomized, double-blind, crossover study. Blood was sampled every 5 min during a baseline period and following infusion for 60 min in total for glucose, fructose, lactate and insulin levels.
Results: No significant brain BOLD signal changes were detected in response to IV saline. BOLD signal in the cortical control areas increased during glucose infusion (p = 0.002), corresponding with increased plasma glucose and insulin levels. In contrast, BOLD signal decreased in the cortical control areas during fructose infusion (p = 0.006), corresponding with increases of plasma fructose and lactate. Neither glucose nor fructose infusions significantly altered BOLD signal in the hypothalamus.
Conclusion: In normal weight humans, cortical responses as assessed by BOLD fMRI to infused glucose are opposite to those of fructose. Differential brain responses to these sugars and their metabolites may provide insight into the neurologic basis for dysregulation of food intake during high dietary fructose in

What that says to me is there is some reason why the brain processes these sugars differently...but we're not entirely sure. The key is "may provide insight" in the conclusion. Now, that may be fleshed out a little differently in the rest of this paper, so I'll do my best to get my hands on it and figure out exactly what else is said.

I did find an article by Dr. Joseph Mercola, who is "a web entrepreneur and alternative medicine guru who markets a variety of dietary supplements and medical devices as part of his diet- and lifestyle-based approach to health". Thanks Google. :)

His reaction to that paper, and I assume he has access to the full paper as he is a physician, can be found here: http://articles.mercola.com/sites/articles/archive/2011/02/28/new-study-confirms-fructose-affects-your-brain-very-differently-than-glucose.aspx

His high-levels-of-fructose-lead-to-impacted-health idea is echoed in this pamphlet (is it a pamphlet? I never know what to call electronic things of this nature) from the British Columbia Medical Association. This one didn't require a fee to view... insert joke about free Canadian medical care here. 

*After learning about the digestive tract and what enzymes and acids are released at which points during eating and digestion.... I swear I can feel those processes happening as I eat if I'm not distracted by something else. It's a very cool but very very gross feeling.

No comments:

Post a Comment