Saturday, May 07, 2011

Fat is Good for Damaged Hearts

Contrary to what we’ve been told, eliminating or severely limiting fats from the diet may not be beneficial to cardiac function in patients suffering from heart failure, a study at Case Western Reserve University School of Medicine reports.

Results from biological model studies conducted by assistant professor of physiology and biophysics Margaret Chandler, PhD, and other researchers, demonstrate that a high-fat diet improved overall mechanical function, in other words, the heart’s ability to pump, and was accompanied by cardiac insulin resistance.

“Does that mean I can go out and eat my Big Mac after I have a heart attack,” Dr. Chandler says “No, but treatments that act to provide sufficient energy to the heart and allow the heart to utilize or to maintain its normal metabolic profile may actually be advantageous.”

The research, published in American Journal of Physiology-Heart and Circulatory Physiology, 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.

In a healthy person, the heart uses both fats and carbohydrates to obtain the energy it needs to continue pumping blood 24/7. Ideally, fats are utilized because they yield more energy.

However, if a person develops heart failure (or suffers from ischemia – a lack of blood supply), the heart seems to prefer using glucose for fuel, because glucose requires less oxygen to produce energy.

While heart disease remains the leading cause of death in the United States, more people are surviving heart attacks that ever before. Survivors though pay a price for this improved survival, living with a damaged heart that usually progresses to heart failure. And unfortunately, medications and procedures have yet to “cure” heart failure, or halt the deterioration of heart function.

Upon initiation of these dietary intervention studies, researchers previously thought a high-fat diet fed to animal models that have suffered a heart attack, would overload their tissues with fat, which in turn would have a toxic effect on their hearts.

Surprisingly, the heart’s pump function improved on the high-fat diet. Through further testing, the researchers found that animal models suffering from heart failure and receiving a low fat diet were able to produce insulin and take up glucose from the blood, just as healthy hearts do. However, the biological models with heart failure that were fed high-fat diets showed signs of insulin resistance, exhibited by a decreased amount of glucose taken up by the heart, as might be expected in a diabetic patient.

One of the main implications of these findings is that contrary to previously held beliefs, a state of insulin-resistance might actually be beneficial to a failing heart. The hypothesis, according to Dr. Chandler, is that because the heart is being provided with excess amounts of fats, it is forced to utilize its preferred energy source.

After suffering an injury that leads to failure, the heart cannot do this on its own, so the researchers have to manipulate its metabolism to use the energy source that maximizes or maintain its function as near to “normal” as possible.

“We want to provide an environment for the heart which allows it to be as effective and efficient a pump as possible, regardless of the damage it has undergone,” Dr. Chandler says.


Princely incomprehension of the market in food

Yesterday, Prince Charles gave a speech in Washington on ‘sustainable farming’. Specifically, he criticised America’s taste for beef, and promoted organic food. But Charles’ comments betray a – perhaps unsurprising – lack of free market understanding and, if put into practice, would amount to an assault on the consumer.

Firstly, the Prince claimed that, “For every pound of beef produced in the industrial system, it takes two thousand gallons of water. That is a lot of water and there is plenty of evidence that the Earth cannot keep up with the demand”.

However, it is a simple law of markets that the Earth can keep up with any level of demand, for any product. If demand exceeds supply at a given price, prices will rise, until supply and demand are re-equilibrated. Increasing water prices will mean that beef is more expensive, naturally regulating the American consumption that Charles is so worried about.

Water goes to beef production because steak, burgers and so forth are highly valued; if we were to ration the amount of water used in making beef, it would go to some other good which is less valued. Since water rationing would also necessarily mean beef rationing, prices would increase nonetheless. The consumer, and in particular the less well-off consumer looking for cheap food, would be hit the hardest.

Prince Charles’ next target was the building on rural land. He criticised the US for allowing such activities, saying that, "Here in the United States I am told one acre is lost to development every minute of every day, which means that since 1982 an area the size of Indiana has been built over".

But what does the transforming of rural land into built up areas show? It shows that the built up areas are valued more highly by the public; people are prepared to pay more for, say, hiring an office block for a year, than they are for the food which could be produced in that land in a year. By placing restrictions on building, the land will be used for something less valued by the public, and the supply of housing will be reduced; leading to an increase in prices. Again, we see consumers, and especially poor consumers in need of housing, taking the hit for such a change.

Lastly, Charles argued for subsidies to organic farming. But all subsidies do is force people to pay towards the production of a good they don’t want. Organic food is expensive because it inefficiently uses resources. If people are prepared to pay for its possible health benefits – fine. But by subsidising organic food, all we’re doing is encouraging resource inefficiency to make food people don’t want.

The land, labour and capital which would have been used to produce a large amount of non-organic food would then be used to make a small amount of organic food. Supply falls, prices goes up, and who loses out? The consumer.


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