- WASHINGTON - Replacing meat with soy substitutes and fresh fruits and vegetables
can significantly lower blood cholesterol levels, Canadian researchers
- They said they were able to reduce the
levels of "bad" low density lipoprotein (LDL) cholesterol in
healthy middle-aged men and women by replacing the meat in their diets
with soy substitutes, vegetables and beans over two one-month periods.
- "We're only beginning to understand
the potentially powerful health benefits of soy," David Jenkins, a
professor of nutritional sciences at the University of Toronto, who led
the study, said in a statement.
- "These findings demonstrate the
power of certain foods in the fight against cholesterol and may explain
why heart disease is so rare in East Asian countries where soy consumption
is much higher."
- The 31 men and women who the researchers
studied all had high blood cholesterol, which has been linked to heart
disease. Some were overweight and some were not.
- Jenkins' team gave the subjects ready-made
meals containing soy instead of meat, as well as soy "cold cuts,"
which are widely available at health food stores. The subjects also were
given extra servings of oats, barley and legumes such as lentils or beans.
- They were asked not to change their exercise
- Half the volunteers received this special
diet, while half were put on a low-fat diet that matched current recommendations
for lowering cholesterol but which included meat and no extra soy. Then
the two groups were switched.
- Adding soy and legumes to the low-fat
diet produced measurable effects, Jenkins reported in the journal Metabolism.
- "Significant blood lipid (fat) reductions
were seen by two weeks," the researchers wrote in their report.
- Members of the soy group had their overall
cholesterol lowered, on average, by 6 percent, with LDL reduced by 6.7
percent on top of any reductions seen in the low-fat diet.
- "Good" or high-density lipoprotein
(HDL) cholesterol levels remained at their previous levels.
- The researchers said adding soy and legumes
greatly boosted the amount of soluble fiber in the diet " something
doctors long have recommended.
- "Vegetable proteins in general tend
to result in lower serum (blood) cholesterol levels compared to animal
proteins," they wrote.
- In a second study, presented last weekend
at the Canadian Federation of Biological Societies meeting in Winnipeg,
Jenkins said he found that smaller amounts of the same soy food prevented
oxidation of the LDL in his volunteers.
- Oxidation, the same process that leads
to rust on metal, causes fats to harden and helps them form the blockages
that damage arteries.