Levels of the cytokine tumor necrosis factor-alpha (TNF-a) also dropped, but in a more modest way, by 0.2 percent and 2.3 percent in the low- and high-dose groups, respectively. The placebo group's TNF-a increased by an average of 12 percent.
IL-6 and TNF-a are two of a family of six cytokines that, when stimulated, produce an inflammatory response to a stressor such as an injury or infection, said study co-author Ron Glaser, professor of molecular virology, immunology and medical genetics and director of the IBMR.
"You need this good inflammation for an initial response, but if it stays up, and inflammation becomes chronic, then you've got a problem," Glaser said. "Our research and studies done by others have shown that these two cytokines are clearly related to overall health and when they're elevated in the blood, that is not good for overall health. So the more ways we can find to lower them, the better."
Statistically, there was no significant difference in lowered inflammation between the two doses, but each dose clearly produced cytokine reductions that differed significantly from the placebo group.
"These data support the idea that a higher dose of omega-3 is not necessarily better than a lower dose in terms of prevention of inflammation," said Martha Belury, professor of human nutrition at Ohio State and a co-author of the study.
However, levels of omega-3 fatty acids in participants' blood increased according to which dose they consumed, which improved their ratio of omega-6 fatty acids to omega-3 fatty acids. The current typical American di
|Contact: Jan Kiecolt-Glaser|
Ohio State University