By Katherine Hobson / US News and World Report
Pick your point of view: Salt is a poison that brings on high blood pressure, which in turn kills via heart attack and stroke. Or, salt is no big deal. It raises blood pressure in only some people, and for everyone else there’s no reason to cut it from your diet.
As with many medical debates, there is no absolute answer, though the negatives about sodium — a key element of salt — are well known. It can boost blood pressure by causing people to retain water. The government now tells healthy adults to cap sodium consumption at 2,300 milligrams (per day) — well under the 4,000 or so Americans now take in on average.
But the logic isn’t ironclad. No one really knows if salt causes the most common form of high blood pressure. Studies suggest that it’s a culprit but also that it’s aided and abetted by a lack of potassium and calcium, too much stress, and obesity. Research hasn’t settled the issue because it’s hard to count every grain that crosses people’s lips, and you need a huge number of participants, tracked for many years, to statistically settle the question of whether excessive salt equals death. One recent review of nearly 30 trials found that cutting salt for at least a month reduced blood pressure by a small amount in people with high blood pressure and an even smaller amount in healthy people. That’s in line with the results of most other studies, though a handful have shown no benefit at all to salt restriction.
The findings probably mask the fact that some people’s genes and lifestyles mean their blood pressure will spike at the slightest whiff of soy sauce, while others can gulp the stuff without a budge in their numbers. Ditch diggers working in the sun all day probably need more salt than a petite office worker does, notes Michael Alderman, former president of the American Society of Hypertension.
A pragmatic recommendation on salt restriction for those of us who aren’t hypertensive comes from Charles Hennekens, an epidemiologist at Florida Atlantic University, Boca Raton: “In my own view, the preponderance of evidence is that too much salt is harmful, or at least not helpful.” In other words, to be safe, it probably doesn’t hurt to follow the government’s advice.
But focusing the entire blood-pressure message on salt is misguided. It ignores, for example, a recent study showing that not only did cutting sodium help blood pressure regardless of diet but that the converse also held true. Eating a lower-fat diet rich in fruits, veggies, and low-fat dairy products also improved blood pressure, regardless of sodium levels.
The point is that cutting salt is not the only route to lowering blood pressure. “We’re trying to give people a palette of options,” says William Vollmer, senior investigator at the Kaiser Permanente Center for Health Research (Portland, Oregon) and one of the study’s authors. Most processed and fast foods aren’t a big part of either a low-sodium or a generally healthy diet. The Center for Science in the Public Interest (Washington, D.C.) is focusing its anti-salt ire on processed and restaurant foods. Swanson’s Hungry Man XXL roasted carved turkey dinner tops its hit list, with 5,410 milligrams of sodium.
If you’re concerned about your overall health and weight (and who isn’t?), the best bet is to avoid most processed foods and instead focus on a broad, nutritious diet, including lean protein.
Source: detnews.com
December 6th, 2005
By Alice Lesch Kelly and Rosie Mestel / Los Angeles Times
Tea, to China’s 18th-century Emperor Chien Lung, was more than a whistle-wetting pick-me-up: It was “that precious drink which drives away the five causes of sorrow.”
Western businesses are banking on our buying into Chien Lung’s sentiments. In addition to selling a cornucopia of loose green teas, they have distilled the brew’s essence and added it to health bars, supplements, diet aids, gum, soft drinks and skin creams — even, in Asia, to Kit Kat candy bars.
Green tea is good for us: That mantra has been chanted in the West since the early 1990s, when studies reported that the infusion, sipped for centuries in China and Japan, appeared to help fight off cancers when drunk by lab mice or rubbed on their skin. Enthusiasm intensified after other studies revealed that green tea contained certain chemicals with cancer-fighting clout. Scientists rolled up their sleeves to figure out how it works.
Today, green tea imports are soaring.
“Ten years ago, 3 percent of imported tea was green tea. Now it’s 12 percent,” says Joe Simrany, president of the Tea Association of the U.S.A.
So confident was one doctor-turned-green-tea businessman that in 2004 he decided to petition the Food and Drug Administration to permit green teas to sport cancer-fighting health claims on their packages.
The FDA’s response: tepid. At best.
In June, the agency ruled that there was “no credible evidence” green tea fights cancers of the stomach, lung, colon, esophagus, pancreas or ovary. The agency acknowledged that the evidence for tea fighting breast or prostate cancer was somewhat better, although it also said the link was “highly unlikely” because the evidence on humans wasn’t conclusive enough.
Scientists say that despite the unanswered questions, green tea still shows promise not only as a potential cancer-protector but also against other health threats, such as cardiovascular disease and possibly Alzheimer’s. But they also are mindful that many a cell in a dish has been vanquished, and many a mouse cured of cancer, from therapies that don’t ultimately pan out in humans.
“You can build your case in cell studies and animal studies but ultimately you have to do it in humans or you can’t make a case that it works,” says Balz Frei, a professor of biochemistry at Oregon State University.
How the tea is processed
Green tea is made from the dried leaves of Camellia sinensis, an evergreen shrub native to Asia. The plant is harvested and treated in different ways to produce green tea or black tea.
Green tea is made by steaming the crushed leaves shortly after harvest, destroying enzymes so that chemicals aren’t oxidized very much.
Leaves used for black tea ferment for days before they’re heated, causing the leaves to blacken and many chemical changes within them.
Those processing differences may be medicinally important. Both types of tea are abundant in certain antioxidant chemicals called flavonoids, which obstruct the action of cell-damaging free radicals. Green tea, because it doesn’t ferment, has much higher levels of a group of flavonoids called catechins. A potent catechin, epigallocatechin gallate, or EGCG, is three to four times more abundant in green tea than black.
Anti-cancer evidence
Scientists cite three lines of green tea anti-cancer evidence.
First, there are test-tube studies. Green tea’s flavonoids interfere with cancer-related biochemical reactions: They may cause cancer cells to grow sluggishly, cease dividing or even self-destruct. Flavonoids also impede formation of carcinogens known as heterocyclic amines.
Then there are studies in rodents. In one fairly typical study, mice were injected with a tobacco carcinogen that caused them to develop lung tumors. Some of the mice drank green tea, and others did not. The tea-drinking mice got fewer tumors.
Similar studies have linked green tea to protecting against a range of cancers — such as those of the lung, skin, esophagus, colon, bladder and possibly the mammary glands.
EGCG isn’t the only thing having an effect. Caffeine is probably providing the lion’s share of protection in the case of the skin cancer experiments, and plays a big part in the lung ones, says green tea researcher Chung S. Yang, who chairs the chemical biology department at Rutgers University in New Jersey.
The third line of evidence is the one people care most about: What happens to humans when they drink tea? Such studies, because they’re usually not done in controlled groups, are tricky to interpret, partly because it’s hard to measure how much tea people drink, and partly because tea-drinkers do a lot of other things. For example, it’s common in China that men who drink a lot of tea also smoke, Yang says.
Studies look promising
The few human studies that have been done have produced mixed results. But despite the complexities, some studies do look good, scientists say.
For example, in an article published in the International Journal of Cancer in 2003, scientists looked at the eating and drinking habits of more than 1,000 Chinese-, Japanese- and Filipino-American women in Los Angeles. They reported that women who drank green tea had a 43 percent lower risk of getting breast cancer compared with women who drank no tea. The more green tea the women drank, the lower their risk of breast cancer, according to the study.
Studies like these were enough to persuade Dr. Sin Hang Lee, a doctor in Connecticut, to start Dr. Lee’s TeaForHealth, a company that sells organic green tea, and to petition the government in January 2004. Lee asked that the FDA allow green-tea producers to label their products with a claim — known as a “qualified health claim” — stating that drinking 40 ounces a day of green tea containing specific amounts of EGCG may reduce the risk of certain forms of cancer. Lee’s FDA petition included stacks of green-tea studies.
When the FDA rejected Lee’s petition, it denied outright any claim for some cancers and awarded decidedly limp qualified health claims for breast and prostate cancer.
The FDA isn’t alone in its skepticism. The American Cancer Society also concluded that more research is needed to show that green tea helps prevent cancer, and many other scientists concur.
Population studies also are intriguing: Last year, for instance, a Chinese study published in the Archives of Internal Medicine reported that people who drank green or black tea had a 46 percent to 65 percent lower risk for high blood pressure.
As for fighting cancer, other human clinical studies are underway in the U.S. If these find evidence that green tea prevents cancer, tea producers say they will petition the FDA again.
If stronger evidence came to light, “we’d re-evaluate the evidence,” the FDA’s Elwood says. “Science evolves.”
Source: detnews.com
December 6th, 2005
Laboratory research indicates that cholesterol plays a role in the development of the waxy deposits, or plaques, that clump together in the brain and characterize Alzheimer’s. Leaping from the petri dish to the body, might lowering cholesterol through medication affect the development of the disease?
This study monitored the progression of dementia in 342 people diagnosed with Alzheimer’s disease. About 68 percent of them had high cholesterol, and more than half of that group was taking a cholesterol-lowering drug (mostly statins). After nearly three years, Alzheimer’s had progressed more slowly in people taking the drugs than in those with untreated high cholesterol or normal levels. Scores on a standardized exam (with a 30-point scale) used to test dementia declined 1.5 points a year for those taking cholesterol medication, compared with a drop of 2.4 points for the untreated high cholesterol group and 2.6 points for those with normal levels.
Who may be affected by these findings? Anyone with Alzheimer’s disease, which affects about 4.5 million Americans — a number that is projected to climb to nearly 16 million in 15 years.
Source: detnews.com
December 6th, 2005
By a correspondent
HYDERABAD: Properly cooked chicken are safe to eat with no threat of bird flu virus said a joint statement by Food and Agriculture Organization (FAO) specialized body of United Nations and the World Health Organization (WHO) issued to national food safety authorities across the globe.
“However, no birds from infested flocks should enter the food chain,” a copy of the statement received by The News on Monday said.
The FAO and WHO made the statement to clarify food safety issues in relation to the current bird flu crisis.
The statement has been issued through the International Food Safety Authorities Network (INFOSAN) and is available in six languages.
In areas where there is no bird flu outbreak in poultry, there is no risk that consumers will be exposed to the virus via the handling or consumption of poultry and poultry products.
Cooking of poultry (e.g. chicken, ducks, geese, turkeys and guinea-fowl) at or above 70 Celsius throughout the product, so that absolutely no meat remains raw and red, is a safe measure to kill the H5N1 virus in areas with outbreaks in poultry FAO/WHO said.
Cooking at high temperature ensures that no active virus remains if the live bird had been infected and had mistakenly entered the food chain. To date, there is no epidemiological evidence that people have become infected after eating contaminated poultry meat that has been properly cooked.
According to available information, a large number of confirmed human cases acquired infection during the home slaughtering and subsequent handling of diseased or dead birds prior to cooking.
FAO and WHO emphasize that in the process of killing and preparing a live bird for food, slaughtering poses the greatest risk of passing the virus from infected or diseased birds to humans.
Most strains of avian influenza virus are mainly found in the respiratory and gastrointestinal tracts of infected birds, and not in meat. However, highly pathogenic viruses, such as the H5N1 strain, spread to virtually all parts of an infected bird, including meat. Proper cooking at temperature at or above 70C in all parts of the product will inactivate the virus.
It is not always possible to differentiate infected and non-infected birds in outbreak areas. Some avian species, such as domestic ducks, may harbour the virus without displaying symptoms.
Therefore, people need to be fully informed about preventive measures, including the use of protective equipment. The practice of slaughtering and eating of infected birds, whether diseased or already dead, must be stopped, FAO and WHO warn. These birds should also not be used for animal feed.
Highly pathogenic avian influenza virus can be found inside and on the surface of eggs laid by infected birds. Although sick birds will normally stop producing eggs, eggs laid in the early phase of the disease could contain viruses in the egg white and yolk as well as on the surface of the shell.
Proper cooking inactivates the virus present inside the eggs. Pasteurisation used by industry for liquid egg products is also effective in inactivating the virus.
Eggs from areas with outbreaks in poultry should not be consumed raw or partially cooked (i.e., with runny yolk), FAO/WHO advise. To date, there is no epidemiological evidence to suggest that people have been infected with avian influenza by consumption of eggs or egg products.
Source: jang.com.pk
December 6th, 2005
