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HEALTH

PORK LINKED TO LIVER CIRRHOSIS

from Canadian Science News by Carolyn Hoskins

(source - from Identity magazine Canada 1985)

For the first time, researchers have shown a possible link between cirrhosis of the liver and dietary factors other than alcohol.

The recent findings of an Ottawa research team show that people who drink, even in moderation, and consume pork are more likely to suffer the potentially fatal liver disease than are people who consume other meat or just fatty diets.

Dr. Amin A. Nanji, Head of Clinical Biochemistry at the Ottawa General Hospital, and Samuel W. French, Chairman of the Department of Pathology at the University of Ottawa, investigated the relationship between per capita consumption of total fat, beef, and pork in several countries and the mortality rates for cirrhosis of the liver in these same countries. They focussed their study on countries where alcohol consumption was relatively low, such as Canada, the US, West Germany and Australia (7.5 to 11. 0 litres per person a year).

Dr. Nanji says previous reports had shown a high rate of deaths from cirrhosis in countries where alcohol consumption was very high but a "Curious scatter" of deaths in countries where alcohol consumption was low.

In other words, countries with low levels of alcohol consumption showed a great variation in the incidence of cirrhosis deaths. Dr. Nanji concluded that some other factor besides alcohol must be at work.

Cirrhosis of the liver is a leading cause of death in North America. In the early stages of this degenerative disease, the liver becomes infiltrated by fat, a condition called 'alcoholic fatty liver'. This condition can be reversed.

In the later stages of cirrhosis, normal liver tissue is gradually replaced by fibrous tissue, the liver structure becomes misshapen and disorganized, and the liver cannot recover. Eventually the victim dies from liver failure.

When the Ottawa team examined the diets of the countries in their study, they found no relationship between deaths from cirrhosis and dietary fat or beef consumption. However, they did find a striking correlation between pork consumption and cirrhosis mortality for the same seven countries. When they examined the relationship in terms of pork consumption multiplied by alcohol consumption, the results were overwhelming.

The two scientist also compared similar data from Canada's ten provinces. Again cirrhosis mortality was significantly associated with pork consumption, but not with alcohol consumption - presumably because Canadians as a group are not heavy drinkers. When the researchers left Newfoundland and Prince Edward Island, where more seafood is eaten, out of their calculations, there was an even stronger link between the fatal liver disease and pork consumption.

Even more convincing to the researchers were comparisons of pork consumption and its effect on cirrhosis death rates within a population. Among the Canadian provinces, where alcohol consumption varies little between provinces (from 9.23 litres per person a year in New Brunswick to 13.05 in Alberta) the death rates from cirrhosis were directly related to per capita pork consumption, but not to alcohol intake.

For example, although Albertans drink slightly more than people in B.C. do, they suffer far less from cirrhosis deaths than do people in B.C., who have a higher pork intake.

Dr. Nariji says the researchers don't know how pork might cause or enhance cirrhosis of the liver. Nor should their study be taken to mean that alcohol does not cause liver disease, he says.

But other researchers have speculated that 'some �facilitating factor� might explain why only some alcoholics get cirrhosis. The Ottawa team may have found part of the answer, Dr. Nanji says.

Drs. Nanji and French hope to follow their statistical study with a �case control study� in which they will investigate meat consumption of individual alcoholic and cirrhotic patients. They also plan to initiate rat feeding studies to investigate the possible role of unsaturated and saturated fats in chronic alcoholism.