A Penn State study has shown that a diet rich in alpha-linolenic acid (ALA), an essential fatty acid found in flaxseed oil, walnuts and walnut oil, not only lowered bad cholesterol but also decreased markers for blood vessel inflammation in men and women.
The study included 20 men and 3 women, average age about 50, who were overweight, had moderately elevated cholesterol and LDL cholesterol and were representative of individuals at risk for cardiovascular disease. On average their total cholesterol was 225, LDL cholesterol 154, HDL cholesterol 45 and triglycerides 137 mg/dl.
The participants ate three experimental diets. One diet approximated the average American diet (AAD). Another, the linoleic acid (LA) diet, included an ounce of walnuts and a tablespoon of walnut oil. The third, the alpha-linolenic acid (ALA) diet, included the walnuts and walnut oil as well as a teaspoon of flaxseed oil. The participants consumed each diet for six weeks. Then they took a two-week break before beginning the next diet. At the end of each 6-week diet period, they provided blood samples so that their cardiovascular risk factors could be monitored.
Compared to the average American diet, both the LA and the ALA diets lowered total cholesterol about 11%, LDLs about 11 or 12% and triglycerides about 18%. After six weeks on the diet, CRP declined after both the LA and ALA diets but more so on the ALA diet that included flax oil. Some participants had a dramatic reduction in CRP.
Penn State University, Nov 8, 2004