USA: Salt restriction may not be a good idea, after all!

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CHICAGO, Illinois / NewsatJama / Author Insights / May 3, 2011

"If you decrease sodium intake a lot, you activate some of the systems that conserve sodium and they are known to have a negative influence on cardiovascular outcomes."

National policies that advise restricting sodium (salt) intake to reduce the risk of hypertension might not provide the anticipated cardiovascular benefits and may even be detrimental to health.

A report in today’s JAMA that in one study, the researchers categorized 3681 study participants according to sodium intake, using a procedure that measures sodium in the urine over a 24-hour period, considered the gold standard for such assessment. At a median of nearly 8 years later, participants in the group with the lowest sodium intake at the beginning of the trial were significantly more likely than the other 2 groups to die of cardiovascular disease.

The researchers also found that these 3 groups had the same risk of developing hypertension, regardless of initial sodium intake. They did find in a subgroup of 1499 study participants who had sodium intake measured at the beginning and at the end of the study that an increase in sodium intake was associated with an increase in systolic (but not diastolic) blood pressure. However, this relationship did not result in a higher risk of complications from hypertension or cardiovascular disease, such as heart attack or stroke.

Research by Jan A. Staessen, MD, PhD, of the University of Leuven in Belgium and colleagues, raises questions regarding whether population-wide sodium restriction will actually lower cardiovascular risks. (Image: University of Leuven)

Jan A. Staessen, MD, PhD, professor of medicine at the University of Leuven in Belgium and one of the study’s authors, discusses his team’s findings:

news@JAMA: Are you surprised by your results?

Dr Staessen: Not so much. We started this research more than 25 years ago, and in all our studies, it was almost impossible to find an association between blood pressure and 24-hour sodium excretion. We were a bit surprised to see an inverse relationship between sodium intake and cardiovascular death.

news@JAMA:  Why would lowering sodium intake possibly increase cardiovascular risk?

Dr Staessen: Ours is an epidemiological study so we cannot be sure of the underlying mechanism. But if you decrease sodium intake a lot, you activate some of the systems that conserve sodium and they are known to have a negative influence on cardiovascular outcomes. This may be an underlying mechanism.

news@JAMA: Where does your study fit into the discussion of mandating sodium restriction in foods to improve health, as advocated by some public health officials and government agencies?

Dr Staessen: One should be very careful when one wants to implement [sodium restriction], as it is based on short-term studies mainly in hypertensive populations. Whether one can extrapolate these short-term results over the long term remains to be seen, especially as our study and 2 previous studies have shown an inverse association between sodium intake and mortality.

news@JAMA: What is needed to provide a clearer picture of the benefits and risks of controlling sodium consumption?

Dr Staessen: What one needs is a long-term interventional study to look at cardiovascular complications. Reducing blood pressure is not what one is in this for. You want to show that it actually changes cardiovascular outcomes.

Source: news@JAMA

BELGIUM: Where's the Beef? Ghent Goes Vegetarian

. NEW YORK, NY / TIME Magazine / World / Postcard from Ghent / May 27, 2009


By Eben Harrell


The Flemish city of Ghent, which has collectively decided to try vegetarianism one day a week.

  Last year, Rajendra Pachauri, chairman of the U.N. Intergovernmental Panel on Climate Change, suggested that the most useful step ordinary citizens could take to help combat climate change would be to stop eating meat. In Belgium, an entire town is taking his advice to heart. The Flemish city of Ghent has designated every Thursday as "Veggiedag" — Veggie Day — calling for meat-free meals to be served in schools and public buildings, and encouraging vegetarianism among citizens by promoting vegetarian eateries and offering advice on how to follow a herbivorous diet. Veggie Day is not compulsory, says the city's vice-mayor, Tom Balthazar, because such a draconian measure would be impossible to enforce, even in environmentally friendly Ghent, a picturesque town of 230,000 where bicycles lay scattered against spired churches in the largest car-free city center in Belgium. "We wanted our goal to be easily achievable — it's not hard to skip meat one day a week," he says. "And we wanted it to be something the population could rally behind. If you give people the correction information about meat, it becomes an easy ethical decision."

(Read "Should We All Be Vegetarians?") 

According to the U.N.'s Food and Agriculture Organization, meat production accounts for 18% of annual greenhouse-gas emissions — more than transportation, which accounts for roughly 14%. Each year, millions of acres of rain forest are cleared for cattle ranchers and suppliers of animal feed, further accelerating climate change. Then there are the urgent human-health issues: the world feeds much of its grain to cattle and other animals even as millions of people starve. Those wealthy enough to consume fatty animal products are themselves at higher risk of certain health problems, including heart disease and some cancers.

(See pictures of the U.N.'s efforts to feed the people of Uganda.) 

For these reasons, says Tobias Leenaert, co-director of Ethical Vegetarian Alternative, a nonprofit funded by the regional Flemish government, "it's almost impossible to be against meat reduction. You can argue against vegetarianism, but not against cutting back on meat." That's a view that is gaining traction among those who hope to reshape meat consumption from an animal rights issue into an environmental and public health one. The Johns Hopkins Bloomberg School of Public Health in Baltimore, for example, recently spearheaded a "meatless Mondays" campaign in which it and 28 other public health schools run local outreach programs that promote a meat-free start to the week.

Germany's federal environment agency issued an advisory earlier this year urging Germans to return to prewar norms of eating meats only on special occasions. And Leenaert says that since Ghent's Veggie Day was launched on May 13, environmental health officers from several other cities — including São Paulo, with a population of 13 million — have expressed interest in mimicking the program. But instituting such well-intentioned programs can be difficult, as I discovered during a trip to Ghent on its most recent Veggie Day on May 21. While most restaurants owners and residents I spoke to had heard of Veggie Day, few had any plans to embrace the concept. A local rib shack, Amadeus, was doing brisk business, and many people openly ate hot dogs on the street. Wim De Kinder, owner of the upscale Traiteur Grimod delicatessen, said he tried to introduce vegetarian fare two years ago after learning of the environmental cost of livestock production, but he couldn't shift enough product to make it profitable. "I can't be expected to make a loss for the sake of principle, however worthy," he says. And it's clear that Ghent still has some ways to go in its promotion of a healthy lifestyle, even among the city's enlightened vegetarians. "I already follow a vegetarian diet for health reasons," insists Mareije Vanneck, 29, as she sucks on a cigarette.

Lees Molenschot, a 64-year-old pensioner sitting in a local pub, says he eats only one meal a day, and always without meat, before adding, "I start out with a coffee in the morning, then five or six beers during the day, maybe some Jägermeister, and then at 6 I make a healthy meal of vegetables in olive oil." But Leenaert of Ethical Vegetarian Alternative says Ghent's public education program is still young. The city council has yet to mail out the 90,000 leaflets it has printed for residents explaining the global benefits of reducing meat consumption, and Veggie Day has yet to roll out in local schools, which will happen when they reconvene in September. He points out that there are historical antecedents for meat-free days, and that it is only recently that people have come to expect meat to be a daily ritual. For centuries in Catholic Europe, for example, citizens forsook meat on Fridays, fast days and Lent. Leenaert, a committed vegan, says governments may have to lay down such restrictions in the coming years as more people in the developing world become wealthy enough to eat meat, but room for livestock diminishes. He hopes, however, that the joint challenges of feeding the world and tackling climate change can be met without curbs on personal choice. "I have big dreams. I dream not of restrictions, but of a critical mass of enlightened citizens who become vegetarians by choice. Maybe that dream starts here in Ghent."
Read "Take a Bite of Belgium."

 © 2009 Time Inc