A Functional Relationship in a Health Article
I have long complained about the simplistic analyses given in health articles. Saturated fats are bad. Trans fats are bad. Hormone replacement therapy prevents heart attacks. Hormone replacement therapy causes heart attacks. In reality things are much more complex because of the difficulties in experimenting with living being and particularly people, it can take a very long time to sort out all of the complexities. An article today on trans fats actually pointed out the beginnings of this sorting out.
The most vocal critics of trans fats believe that the relationship between their intake and heart disease is linear. Even tiny amounts pose some threat, they say. But an interesting study by Dr. Lichtenstein suggests that it’s more complicated than that.
She and her colleagues put 36 volunteers on diets with various amounts of trans fats, then measured blood levels of L.D.L. and H.D.L. cholesterol.
Increased trans fats were associated with increased blood levels of bad cholesterol in a linear fashion, she found. But good cholesterol was significantly diminished only in subjects who consumed trans fats in the greatest amounts — nearly 7 percent of their daily calories — and even then just barely. H.D.L. was not affected in subjects consuming less.
This finding and others like it suggest that for consumers eating modest amounts of trans fat, the gain from reduced intake may not be as great as some might hope. In any event, the benefit is likely to accrue mostly for people who have elevated cholesterol to begin with. That’s one in four New Yorkers, according to the city’s health department.
“Cumulatively, this small step could have a beneficial effect,” Dr. Lichtenstein said. “But it’s not going to be a panacea.”
The boldface was added by me. I can never remember seeing a popular press article mention a linear relationship between two variables. In addition, the article goes on to point out that the linear relationship holds for LDL but not HDL. This turns out to be very important to me since my LDL is quite good, but HDL is just outside the acceptable range. If this result is true cutting trans fats are unlikely to help me.