Is fish really that good for you?

Michael's Hospital (Toronto, Canada),and his colleagues reviewed a widespectrum of research. While manystudies seemed to demonstrate heart..health advantages, others did not ­including research revealing that non..fish..eaters, such as vegetarians, experi..ence no increased risk of illness.However, such "negative" findings areoften ignored, Jenkins contends.Moreover, he points out, sorting outhow other factors - such as lifestyle ­may influence the results can be diffi..cult, and thus are often not considered.

According to Jenkins' coauthor, fish..

Fishy health claims indoubtNoreen Parks

For years, health authorities haveurged people to consume moreseafood, especially fatty fish (or oilsderived from them), to-increase theirintake of omega..3 fatty acids, toutedfor alleged "healthy heart" benefitsand the power to ward off chronic dis..eases, such as cancer and diabetes.However, a multi..disciplinary analysisin the March issue of CanadianMedical Association]ournal (2009;180: doi:10.1503jcmaj.081274) con..eludes that these claims are exagger..ated, and warns that the escalatingdemand for fish driven by such recom..mendations is exerting unsustainablepressure on fisheries already ham..mered by multiple threats.

To evaluate the evidence forseafood's health..conferring benefits,medical doctor David Jenkins, of St

eries ecologist Daniel Pauly (Uni ..versity of British Columbia, Vancou..ver, Canada), wide consensus exists onthe critical status"of global fisheries, incontrast to the scientific uncertaintyover the value of boosting fish con..sumption. Despite intensified fishing

~ efforts, global harvests have falleni since the late 1980s, while the number.8 of collapsed stocks has risen exponen..~

--u~ tially since 1950. "Projected forward,"c these trends imply the collapse of allQ)

~ commercially exploited stocks by mid..century", Pauly cautions.

The incompatibility between surgingseafood demand and plummeting fish..eries also has socioeconomic ramifica..tions, as fish catches are increasinglydiverted from poorer nations towardnewly affluent and developed countries.

As the researchers point out, omega..3fatty acids are available from otherdietary sources, including walnuts,flaxseed and other vegetable oils,yeasts, and algae. Further research isnecessary to verify the role fish oilsplay in human health, they conclude,particularly since current dietary rec..ommendations to increase fish con..sumption may not be sustainable. •

Fires fuel deforestationcrisis in KenyaJen Schoemburg

In late Marth, forest fires ravaged sev..eral of Kenya's key moisture reservoirs,including the 400000..hectare MauForests Complex. Estimates of totaldamage vary, with some reports that25-35% of the Mau Complex wasaffected. The Mau is Kenya's largestforest-and the source of water for atleast 12 rivers and several lakes,including Lake Victoria, which feedsthe Nile River. Water levels in riversdraining the forest have fallen consid..erably because of extensive deforesta..tion - now compounded by the fires ­which complicates a drought situationthat has affected the food supply forabout 10 million local residents.

Additional fires burned in theAberdares and Karura forests andthreatened nearly 60 species of wildlife,including huge numbers of flamingos,

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that depend on Lake Nakuru for theirsurvival. According to reports, firesdestroyed more than 25% of MountLongonot National Park, and zebras,buffaloes, and giraffes were among thewildlife forced to cross roads and resi..dential areas to reach safety.

The fires intensify an already diredeforestation problem in Kenya, whereillegal settlements, logging, and char..coal burning have depleted the coun..try's forests down to a critical 1.7% ofthe total land area, according to theKenya Forests Working Group (Kili..mani, Kenyaf'Christian Lambrechts, aPolicy and Programme Officer at theUN Environment Programme (UNEBNairobi, Kenya), says "The fires havecontributed further to the degradationof the Mau Forests Complex, whichsupports key economic sectors throughecological services". UNEP estimatesthat the Kenyan government couldlose more than US$300 million peryear from the tourism, tea, and energy

sectors should deforestation continueat its current rate.

Kenya's energy sector is at particularrisk. Say~ Lambrechts, "The US$260million Sondu Miriu hydroelectricityproject, operational since 2007, co~ldbe in jeopardy if deforestation in theMau is not addressed promptly,because the plant depends on waterfrom the forest. An additional 41 % ofKenya's instq.lled energy capacitycould be provided by water from theMau Complex if it remains intact".

Kenyan officials believe the fireswere set deliberately, to "'tiJ.ake spacefor farmland or by members of forestcommunities opposed to govern..ment plans to displace them; severalsuspects have been arrested. Thearrival of the rainy season may bringlittle relief; officials fear that topsoilmay erode, hindering fish breedingin Kenyan lakes, and that floodingmay occur, both resulting fromdeforestation. •

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