Monday, May 23, 2011

High Fat Heart Benefit

It's only a rat study, but still ... high saturated fat levels help your heart work better when under duress?  Sure does sound like saturated fat is supposed to be part of your diet.  Interestingly, the heart reportedly runs very efficiently on ketones, also, which the body produces in abundance on ... a high fat diet.

Now take a look at this published summary - no mention of saturated fats at all, and instead they say the study: suggests that for a damaged heart, a balanced diet that includes mono- and polyunsaturated fats, and which replaces simple sugars (sucrose and fructose) with complex carbohydrates, may be beneficial.
How could this oversight be explained?  I think it is cognitive dissonance - when one has come to believe deeply that saturated fat is the enemy, one can not process the evidence that it is not.  In any event, polyunsaturated fats are not what I would take for health, nor would I bank on "complex" carbohydrates - and I would not trust anyone that even uses that term as many complex carbohydrates have the same powerful, negative metabolic impact as table sugar, if not worse. 

As Kurt Harris has said, saturated fat is like grade A diesel, it is a premium fuel for nearly all the body's cells.  It's what we were build to burn as the "normal" fuel.


Impaired myocardial contractile function is a hallmark of heart failure (HF), which may present under resting conditions and/or during physiological stress. Previous studies have reported that high fat feeding in mild to moderate HF/left ventricular (LV) dysfunction is associated with improved contractile function at baseline. The goal of this study was to determine whether myocardial function is compromised in response to physiological stress and to evaluate the global gene expression profile of rats fed high dietary fat after infarction. Male Wistar rats underwent ligation or sham surgery and were fed normal chow (NC; 10% kcal fat; Sham + NC and HF + NC groups) or high-fat chow (SAT; 60% kcal saturated fat; Sham + SAT and HF + SAT groups) for 8 wk. Myocardial contractile function was assessed using a Millar pressure-volume conductance catheter at baseline and during inferior vena caval occlusions and dobutamine stress. Steady-state indexes of systolic function, LV +dP/dtmax, stroke work, and maximal power were increased in the HF + SAT group versus the HF + NC group and reduced in the HF + NC group versus the Sham + NC group. Preload recruitable measures of contractility were decreased in HF + NC group but not in the HF + SAT group. β-Adrenergic responsiveness [change in LV +dP/dtmax and change in cardiac output with dobutamine (0–10 μg·kg−1·min−1)] was reduced in HF, but high fat feeding did not further impact the contractile reserve in HF. The contractile reserve was reduced by the high-fat diet in the Sham + SAT group. Microarray gene expression analysis revealed that the majority of significantly altered pathways identified contained multiple gene targets correspond to cell signaling pathways and energy metabolism. These findings suggest that high saturated fat improves myocardial function at rest and during physiological stress in infarcted hearts but may negatively impact the contractile reserve under nonpathological conditions. Furthermore, high fat feeding-induced alterations in gene expression related to energy metabolism and specific signaling pathways revealed promising targets through which high saturated fat potentially mediates cardioprotection in mild to moderate HF/LV dysfunction.

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