February 06, 2001
Greg asks: I have recently switched to a vegetarian (but not vegan) diet for health and ecological reasons. This includes eliminating fish from my diet. I understand, however, that fish are an excellent source of "omega-3" fatty acids and that I should have a healthy portion of such acids in my diet.
I've also heard that consuming olive oil on a regular basis can make up for this loss. But I've also heard that other vegetable oils contain these acids in higher quantities than olive oil, and still other reports that suggest that fish are the only true source of omega-3's.
My question is therefore multi-faceted: As a vegetarian, what is the best way for me to ensure that I am getting an adequate supply of omega-3 fatty acids in my diet? Do vegetable oils in fact contain omega-3 fatty acids? Are there any other fruits or vegetables that contain such acids? And are omega-3's really essential to a healthy diet?
Dr. Deane Replies: When we talk about fatty acids there are two considerations. The first is whether it is essential for life, one of the "essential fatty acids". The second consideration is whether it may prevent disease and prolong life. Omega-3 fatty acids have been in the spotlight recently because they may help prevent stroke and heart attacks. The FDA has said "Consumption of omega-3 fatty acids may reduce the risk of coronary heart disease" (2/2002), and the American Heart Association AHA states: "We recommend eating fish two times per week." Omega-3s exert their health benefits by blocking inflammatory substances made by the body and disrupting the function of platelets, a part of the blood clotting machinery. Olive Oil does not have high levels of omega-3 fatty acids but it does have substances, the flavenoids, which exert some of the same effects. The ratio of Omega-3 to other acids is very good in olive oil and it may be that the ratio of these fatty acids is what's most important. There are studies which show that diets rich in olive oil help prevent heart attacks and stroke.
If your personal convictions prevent you from eating fish or fish products, such as fish oil pills and capsules, I think olive oil can help with some of your concerns. A vegetarian diet is generally regarded as one of the healthiest, especially if it includes eggs, fish and dairy. Remember, you don't need to choose one oil to eat for the rest of your life. A nutritious diet would include oils high in omega-3, oils high in flavenoids, and other healthy oils. 9/27/02
Bonnie asks: I am very interested in the apparent benefits of olive oil and since I was told by my own doctor that my blood cholesterol levels were a bit over the average I have taken a keen interest in eating a very healthy diet as well as continuing the medication of one 10mg statin tablet per day, which has reduced my cholesterol to below the average for the part of Scotland I live in! However, I am confused if eating a source of omega3 found in oily fish such as herring, mackeral, sardines etc marinated in olive oil is good or bad for you, as a recent article I read suggested that such a combination was in fact full of fat. Talk about being confused!!!
Dr. Deane replies: The food we eat can be categorized as protein, carbohydrate or fat. All oils are fats. Olive oil and omega3 fatty acids are healthier types of fat than animal fats (which contain cholesterol) and the plant fats which are highly saturated (such as margarines and palm oil). Its best to reduce the total amount of fat in your diet and make sure that what fat you do eat is the healthy kind found in fish and olives.