Eating fish associated with lower risk of dying among older adults

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Older adults who have higher levels of blood omega-3 levels—fatty acids found almost exclusively in fatty fish and seafood—may be able to lower their overall mortality risk by as much as 27% and their mortality risk from heart disease by about 35%, according to a new study from Harvard School of Public Health (HSPH) and the University of Washington. Researchers found that older adults who had the highest blood levels of the fatty acids found in fish lived, on average, 2.2 years longer than those with lower levels.

"Although eating fish has long been considered part of a healthy diet, few studies have assessed blood omega-3 levels and total deaths in ," said lead author Dariush Mozaffarian, associate professor in the Department of Epidemiology at HSPH. "Our findings support the importance of adequate blood omega-3 levels for cardiovascular health, and suggest that later in life these benefits could actually extend the years of remaining life."

The study—the first to look at how objectively measured blood biomarkers of relate to total mortality and specific causes of mortality in a general population—appears online April 1, 2013 in Annals of Internal Medicine.

Previous studies have found that fish, which is rich in protein and heart-healthy , reduces the of dying from heart disease. But the effect on other causes of death or on total mortality has been unclear. With this new study, the researchers sought to paint a clearer picture by examining biomarkers in the blood of adults not taking , in order to provide the best assessments of the potential effects of dietary consumption of fish on multiple causes of death.

The researchers examined 16 years of data from about 2,700 U.S. adults aged 65 or older who participated in the Cardiovascular Health Study (CHS), a long-term study supported by the National Heart, Lung, and Blood Institute. Participants came from four U.S. communities in North Carolina, California, Maryland, and Pennsylvania; and all were generally healthy at baseline. At baseline and regularly during follow-up, participants had blood drawn, underwent physical examinations and diagnostic testing, and were questioned about their health status, medical history, and lifestyle.

The researchers analyzed the total proportion of blood omega-3 fatty acids, including three specific ones, in participants' blood samples at baseline. After adjusting for demographic, cardiovascular, lifestyle, and dietary factors, they found that the three fatty acids—both individually and combined—were associated with a significantly lower risk of mortality. One type in particular—docosahexaenoic acid, or DHA—was most strongly related to lower risk of coronary heart disease (CHD) death (40% lower risk), especially CHD death due to arrhythmias (electrical disturbances of the heart rhythm) (45% lower risk). Of the other blood fatty acids measured—eicosapentaenoic acid (EPA) and docosapentaenoic acid (DPA)—DPA was most strongly associated with lower risk of stroke death, and EPA most strongly linked with lower risk of nonfatal heart attack. None of these fatty acids were strongly related to other, noncardiovascular causes of death.

Overall, study participants with the highest levels of all three types of fatty acids had a 27% lower risk of total mortality due to all causes.

When the researchers looked at how dietary intake of omega-3 fatty acids related to blood levels, the steepest rise in blood levels occurred when going from very low intake to about 400 mg per day; levels rose much more gradually thereafter. "The findings suggest that the biggest bang-for-your-buck is for going from no intake to modest intake, or about two servings of per week," said Mozaffarian.

More information: "Plasma Phospholipid Long-Chain Omega-3 Fatty Acids and Total and Cause-Specific Mortality in Older Adults," Dariush Mozaffarian, Rozenn N. Lemaitre, Irena B. King, Xiaoling Song, Hongyan Huang, Molin Wang, Frank M. Sacks, Eric B. Rimm, and David S. Siscovick, Annals of Internal Medicine, online April 1, 2013

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HealingMindN
1 / 5 (1) Apr 01, 2013
Do these findings include farm raised fish like GM salmon?
Lurker2358
not rated yet Apr 01, 2013
At least the GM Salmon doesn't have botulism added to it like the corn does.
Mike_Massen
5 / 5 (2) Apr 02, 2013
Is Lurker2358 claiming
At least the GM Salmon doesn't have botulism added to it like the corn does.
You do mean the spore forming bacteria ?
http://en.wikiped...otulinum
or are you referring to something else populist under same name ?

Can you not be cryptic, this is a Science site, so something "..a little more detailed.." would be helpful.

Thanks

Edit:
I trust most would be aware the farmed salmon (in pens in the sea) eat their own washed faeces and the meat is normally grey unless a guy with a colour chart comes out a week before harvesting and adds chemicals according to the colour you want the meat to be:- From yellow all the way through to dark orange or even red.

ie. Salmon are a predatory species, having them in pens and consuming some of their own waste is unnatural and reminds me of the issue of cattle being made to be cannibals - which caused the prion disease issue in UK in the 1990's... Lets hope there isn't a similar issue to BSE.
MichelO
1 / 5 (1) Apr 03, 2013
I am sorry, but your mortality rate is 100% no matter what you eat.
atomsk
1 / 5 (2) Apr 05, 2013
Do these findings include farm raised fish like GM salmon?

It depends on what the fish eats.
from Wikipedia:
Although fish is a dietary source of omega−3 fatty acids, fish do not synthesize them; they obtain them from the algae (microalgae in particular) or plankton in their diets
Osiris1
1 / 5 (2) Apr 08, 2013
GM corn is part fly spray. You might as well raise pyrethrum like they do in Africa for a cash crop. Maybe the best thing for oldsters is to eat the fattest fish in the sea, a real fat 'cat'....Charlie the Tuna!LOL