October 31, 1998
Greenbrae, Ca - A web visitor recently asked about the value of olive oil for persons recently diagnosed with atherosclerotic heart disease. There is still a great difference of opinion about oils and health. What people agree on is that less fat is better and unsaturated fats are better than saturated ones. The question is, how low do you go and which oil is better than others.
The truth may be that everyone is different and fats may or may not be a risk factor depending on one's genes. The Mediterranean diet has been shown to lower heart disease but Mediterranean countries people eat as much as 40% of their calories as fats (mostly olive oil). How much of the benefit is from the oil and how much is from the large quantity of nuts, fruits, and vegetables that are consumed? Studies are in progress to try to find out. For patients with low HDL levels and high triglycerides, the Mediterranean diet may lower heart disease best.
Dr. Dean Ornish has risen to national prominence with a diet and lifestyle program which advocates as little as 10% calories from fat. This has been shown to actually reverse atherosclerosis in some studies. Dr. Ornish says high triglycerides and low HDL are risky only for people on high-fat diets. With a lower fat diet your HDL level is less important. But there are a few critics who argue that a diet too low in fat may actually lower the good HDL cholesterol and cause worse damage to arteries. There are plenty of places in the world where heart disease is unheard of, as in rural China where the diet is heavy with complex carbohydrates such as rice and greens and very light in meat and no dairy. That would tend to support Dr. Ornish.
Now what about the different oils? Animal fats have cholesterol so there is a consensus we should avoid them. Plant oils never contain cholesterol but those which are deliberately saturated to stay solid at room temperature cause oxidative damage with resulting accelerated heart disease. Monosaturated fats such as olive oil are best. There is new research that shows that nut oils such as almond oil can lower cholesterol and raise HDL better than olive oil.
As you can see, the jury is still out, there is still controversy about diet and heart disease. My cardiology colleagues all agree though, that lower fat is better. Remember, sopping your bread with olive oil may make you feel like you are doing the healthy thing, but 2 tablespoons of oil is equivalent to 2 scoops of Ben and Jerry's when it comes to total fat.