Errata

1. Thiago Alves, one of the stars of mixed martial arts and the Ultimate Fighting Championship has withdrawn from UFC 111 due to an irregularity found on a CT scan.  He is scheduled to undergo an angiogram on Wednesday.

The CT scan was a routine part of his preoperative medical clearance for the fight.  An “irregularity” was found in the left side of his brain.  It likely represents some kind of vascular anomaly, given the choice of an angiogram to further characterize the lesion.  It has been reported that it is not an aneurysm.  Some of the more common vascular anomalies include arteriovenous malformations, cavernomas, and dural arteriovenous fistulas.  An old stroke would also be visible on a CT scan.  The presence of a stroke could be suggestive of a traumatic vascular dissection, which could also be detected via angiogram.

Lateral cerebral angiogram after contrast injection into the common carotid artery

An angiogram defines the vascular anatomy providing blood supply to the head.  It is a relatively minor procedure.  A small catheter is inserted into an artery, usually in the groin or arm, and then directed to the cerebral blood vessels.  At that point, a small amount of contrast is injected into the blood vessels.  Fluorscopy pictures detect the contrast showing the anatomy and general flow characteristics of the blood vessels.  Abnormalities of the blood vessels can be readily observed.

The good news is that Alves is expected to be able to return to the octagon soon.

2.  Mexican americans, women, and persons who live alone are the least likely to pursue emergency medical assistance following a stroke reports Businessweek.

3.  Neurosurgery better than ‘Avatar’? An operation in Liege, Belgium was recorded in 3-D and transmitted to a local movie theater.  The audience was apparently able to interact with the surgeon in real-time.  I guess I don’t have to give up on my Hollywood aspirations quite yet after all.

The Perils of HFCS

I was wrong.  I was always of the philosophy that a calorie was a calorie was a calorie.  That obesity was based upon a simple formula:

weight change = [calories in] – [calories out]

In other words, if you spent more calories than you consumed, you lost weight.  If you consumed more calories than you spent, you gained weight.

However, a recent study published in the Journal of Pharmacology, Biochemistry, and Behavior suggests that all calories are not created equal.

All calories may not be created equal

The authors fed three groups of rats: one group was given regular chow ad lib.  The second group was given regular chow ad lib and supplemented with sucrose.  The third group was given regular chow ad lib and supplemented with high fructose corn syrup (HFCS).  Although the overall number of calories consumed by the sucrose group and the HFCS groups were the same, the HFCS group gained significantly more weight.

It gets even more interesting.  Fructose, on a per calorie basis, is much sweeter than sucrose.  That is why it has replaced sugar in many food items, particularly soft drinks.  The manufacturer can maintain the sweetness of the product while including fewer calories – tastes great and less filling, or at least fewer calories.

In the current study, however, the sucrose and the HFCS group consumed a similar number of calories overall.  But the HFCS group actually obtained a smaller percentage of their calories from the corn syrup.  The study suggests that the HCFS was able to drive more calories towards becoming fat than sucrose, even when HCFS made up a lower percentage of the total caloric intake.

Actually, this does make sense from a biochemical standpoint.  Fructose is not like the other sugars common in our diet.  Nicholas J Krilanovich described it nicely in a letter to the American Journal of Clinical Nutrition:

Basic biochemistry indicates that glucose and fructose have different chemical properties. Of the 3 major sugars that digest into the human bloodstream, the 2 that are vital to humans, galactose and glucose, are both aldoses, whereas fructose is a ketose—this sugar is the one that the human liver tries hard to keep at essentially a zero concentration in the blood. Murray et al (10) wrote that, “Biomedically, glucose is the most important monosaccharide and ingestion of large quantities of fructose has profound metabolic consequences …because it bypasses the regulatory step catalyzed by phosphofructokinase. This allows fructose to flood the pathways in the liver, leading to enhanced fatty acid synthesis, increased esterification of fatty acids, and increased VLDL secretion, which may raise serum triacylglycerols and ultimately raise LDL cholesterol concentrations.”

I am definitely going to pay more attention to the amount of HFCS I consume.  Perhaps, my math has been wrong all along.  I all likelyhood:

weight change does not equal [calories in] – [calories out]