Walnuts: A Superfood! Maybe BETTER than Olive Oil!

October 24, 2006

Walnuts: A Superfood!  Maybe BETTER than Olive Oil! 

 Competency # 14 Superfood and # 13  Fats                           ReferenceAmerican Journal of Cardiology – Oct 17, 2006 

 Endothelial dysfunction.  That’s the $ 40 word for what happens to your arteries when they get exposed to “bad fats”.   To quote the article,  “Endothelial dysfunction is a critical event in atherogenesis that is implicated both in early disease and in advanced atherosclerosis. It is characterized by a decreased bioavailability of nitric oxide (NO) and increased expression of proinflammatory cytokines and cellular adhesion molecules.

 The predominant mechanism of NO inactivation is a perturbation of the L-arginine–NO pathway by oxidative stress leading to elevations of plasma asymmetric dimethylarginine (ADMA), which in turn exacerbates oxidative stress." Ok, that sounds complicated.  What it boils down to is that your arteries are affected immediately after eating.  Both short-term effects and those short-term effects have long-term implications.   The food you eat makes a difference.  

One way by which arteries show their vulnerability to damage is to constrict, become narrow, and reduce their flow.  You also release inflammatory markers and show oxidation of your fats that are circulating.  Yes, that happens after a single high-fat meal.   This study gave a standardized meal to volunteers and then measured the flexibility and the inflammatory markers in their blood right after the meal.  The variable they measured was olive oil versus walnuts.  It was a 63% fatty meal, of which half the fat was either olive oil or walnuts  (about 8 whole walnuts).  (1200 calories from salami, cheese, white bread – then they added the oil or walnut oil) 

 What they found was that both oils reduced the inflammatory markers in their blood.  We’ve known that olive oil is a great oil.   Blood fats did go up in both groups.  But the huge difference was that the walnut diet had an INCREASE in blood flow whereas the olive oil had a decrease.  That is an indirect measure of all the complicated nasty influences of fats on your blood vessels after a fatty meal.  The Flow Mediated Dilatation (FMD if you want to sound scientific) was –17% for olive oil, and + 34% for walnuts. This study was supported by the folks who grow walnuts.  Does that make it suspect?  We always wait for a few more studies to confirm this kind of stuff.  But their methods and results were well done and rigorous. 

 WWW:  What Will Work for Me.  I’ve always munched on almonds.  I’m going to start looking favorably on walnuts too.  And knowing that a salami and cheese sandwich is over 63% fat, … I’m cutting down on those.  If all this bad stuff happens after a single high fat meal, consider the flip side, how it all can be immediately reversed with a good meal.  Walnuts!

This column was written by Dr. John E. Whitcomb, MD, Brookfield Longevity, Brookfield, WI, (262-784-5300)