Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Omega-3 lowers inflammation in overweight older adults

21.06.2012
New research shows that omega-3 fatty acid supplements can lower inflammation in healthy, but overweight, middle-aged and older adults, suggesting that regular use of these supplements could help protect against and treat certain illnesses.

Four months of omega-3 supplementation decreased one protein in the blood that signals the presence of inflammation by an average of more than 10 percent, and led to a modest decrease in one other inflammation marker. In comparison, participants taking placebos as a group saw average increases of 36 percent and 12 percent, respectively, of those same markers.

Chronic inflammation is linked to numerous conditions, including coronary heart disease, Type 2 diabetes, arthritis and Alzheimer’s disease, as well as the frailty and functional decline that can accompany aging.

Study participants took either 2.5 grams or 1.25 grams of active omega-3 polyunsaturated fatty acids in their supplements. Polyunsaturated fatty acids are considered“good fats” that, when consumed in proper quantities, are associated with a variety of health benefits. Study participants taking a placebo consumed pills containing less than 2 teaspoons per day of a mix of oils representing a typical American’s daily dietary oil intake.

“Omega-3 fatty acids may be both protective so that inflammation doesn’t go up, as well as therapeutic by helping inflammation go down,” said Jan Kiecolt-Glaser, professor of psychiatry and psychology at Ohio State University and lead author of the study.

“This is the first study to show that omega-3 supplementation leads to changes in inflammatory markers in the blood in overweight but otherwise healthy people. In terms of regulating inflammation when people are already healthy, this is an important study, in that it suggests one way to keep them healthy.”

The study is published online and scheduled for later print publication in the journal Brain, Behavior and Immunity.

The scientists recruited 138 adults - 45 men and 93 women - who were in good health, but who were either overweight or obese and lived sedentary lives. Their average age was 51 years. Based on body mass index, a measure of weight relative to height, 91 percent of the participants were overweight and 47 percent were obese.

Inflammation tends to accompany excess body fat, so the researchers recruited participants who were most likely high in pro-inflammatory blood compounds at the beginning of the study.

“We wanted to have enough room to see a downward trend. Most other trials testing the effects of omega-3 supplements on inflammation used people who were seriously diseased or skinny and healthy,” said Kiecolt-Glaser, also an investigator in Ohio State’s Institute for Behavioral Medicine Research (IBMR). “You can see results in people with serious diseases, but there’s a lot of other noise in that system. We wanted to make sure we were studying results in people who were fairly fit but who weren’t exercising, because exercise can clearly lower inflammation.”

The researchers also excluded from participation people taking a variety of medications to control mood, cholesterol and blood pressure as well as vegetarians, patients with diabetes, smokers, those routinely taking fish oil, people who got more than two hours of vigorous exercise each week and those whose body mass index was either below 22.5 or above 40.

Participants received either a placebo or one of two different doses of omega-3 fatty acids - either 2.5 grams or 1.25 grams per day. The supplements were calibrated to contain a ratio of the two fish oil fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), of seven to one. Previous research has suggested that EPA has more anti-inflammatory properties than does DHA.

After four months, participants who had taken the omega-3 supplements had significantly lower levels in their blood of two proteins that are markers of inflammation, also called pro-inflammatory cytokines. The low-dose group showed an average 10 percent decrease in the cytokine interleukin-6 (IL-6), and the high-dose group’s overall IL-6 dropped by 12 percent. In comparison, those taking a placebo saw an overall 36 percent increase in IL-6 by the end of the study.

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 diet contains between 15 and 17 times more omega-6 than omega-3, a ratio that researchers suggest should be lowered to 4-to-1, or even 2-to-1, to improve overall health.

“Scientists tend to agree that the best way to gauge a person’s omega-3 status is to see whether that ratio goes down,” Belury said. “That’s what we saw in this study, and it was achieved through supplementation. We wanted participants to maintain normal diets and simply add this modest amount of oil to their existing diet. We expected and we found that their blood plasma omega-3 fatty acids went up in a dose-responsive manner.”

The Food and Drug Administration considers daily omega-3 supplementation of up to 3 grams to be “generally regarded as safe.” The doses in this study were within those safety parameters, but the researchers did not extend their findings to make a general recommendation about omega-3 supplementation.

“Although omega-3 fatty acids cannot take the place of good health behaviors, people with established inflammatory diseases or conditions may benefit from their use,” Kiecolt-Glaser said.

The researchers also sought to determine whether omega-3 fatty acids could reduce depression symptoms, but participants had relatively few symptoms to begin with so no significant reductions were seen. Depression is also associated with chronic inflammation, but research hasn’t yet fully defined the mechanisms behind that relationship.

This work was supported in part by grants from the National Institutes of Health. OmegaBrite, a company based in Waltham, Mass., supplied the supplements as an unrestricted gift but did not participate in the study design, results or publication.

Additional co-authors, all at Ohio State, include Rebecca Andridge of the Division of Biostatistics; William Malarkey of the IBMR and the departments of Psychiatry and Internal Medicine; and Beom Seuk Hwang of the IBMR and biostatistics.

Contacts:
Jan Kiecolt-Glaser, (614) 293-3499; Janice.Kiecolt-Glaser@osumc.edu
Ron Glaser, (614) 293-0178; Ronald.Glaser@osumc.edu
Martha Belury, (614) 292-1680; Belury.1@osu.edu
Written by Emily Caldwell, (614) 292-8310; Caldwell.151@osu.edu

Jan Kiecolt-Glaser | EurekAlert!
Further information:
http://www.osumc.edu

More articles from Health and Medicine:

nachricht Finnish research group discovers a new immune system regulator
23.02.2018 | University of Turku

nachricht Minimising risks of transplants
22.02.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Attoseconds break into atomic interior

A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.

In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...

Im Focus: Good vibrations feel the force

A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.

By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Basque researchers turn light upside down

23.02.2018 | Physics and Astronomy

Finnish research group discovers a new immune system regulator

23.02.2018 | Health and Medicine

Attoseconds break into atomic interior

23.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>