Blog | Friday, June 15, 2018

Ode to olive oil

As lovingly and lavishly revealed in her own photo-essay on the topic, my wife and I are recently back from co-hosting an Oldways sponsored culinary travel adventure through Sicily. We ate, we drank, we toured, we made friends, we saw the dual beauties of nature and ancient civilization, and then, inevitably, we ate and drank some more!

The trip and the cuisine were both memorable in many particulars, but I will focus here on one: olive oil. We experienced olive oil as only the true artisans of the craft can make it. For the masters of this culinary art, “olive oil” as a generic reference means little more than, say, “wine.” With wine, there is bad and mediocre and good and stunningly great; wine made from these grapes, or those. So, too, for olive oil.

As a wine enthusiast, I have always appreciated the profound importance of just such considerations to the enjoyment issuing from my glass. I confess I never really paused to think much about the variety of olive making its specific, unctuous contribution to the quality of a meal, but of course that matters.

I did not become anything like an expert during our short time in Sicily, nor on other recent occasions when I learned from experts of the olive oil craft from other parts of the world. I only really learned enough to know what a delight the world's great and diverse olive oils can be, and to share such discoveries – courtesy of, for instance, the Taibi Family and Planeta Vineyards in Sicily; and Boundary Bend in Australia.

From the gustatory perspective, then, I can simply say I recognize great olive oil when I taste it, and I love it. Primarily, that's why I eat it. The right olive oil playing the right role, whether in sauce or sauté, salad dressing or for dipping bread, enhances a meal.

I am, as well, a strong proponent of its nutritional properties, and role in an optimal diet. Olives and olive oil are not merely prototypical of the famously healthful, traditional Mediterranean diet, but formally situated among the key anatomical features of that dietary pattern to which favorable health effects are attributed.

The contributions of olive oil to the good health outcomes that matter most, freedom from chronic disease, vitality, and longevity, warrants some discussion, because there are colleagues I respect, and with whom I agree about much, who differ with me here. Among my friends are some who advocate not only for a plant-exclusive (vegan) diet, but such a diet with no added oil and low in total fat. I have heard them argue that olive oil is “bad” for health, and cite studies to validate the claim.

Olive oil consumption in dietary context is strongly and consistently associated with health benefit. How, then, can any credible expert argue it is harmful? There are isolated studies in which putative harms to endothelial function (a measure of blood vessel behavior and blood flow) were shown with olive oil ingestion, likely because of the dose of oil administered, the nature of the oil used, or both. In general, olive oil intake has been associated with improved endothelial function. To put such conflicting findings in context, exercise is also consistently associated with improved endothelial function, and better cardiovascular health, but isolated studies have shown endothelial dysfunction with exercise, comparably related to “dose” (intensity of exercise), and timing of the measures.

I have other colleagues, again with whom I agree about most things diet-related, who feel so strongly that unsaturated fat is the key to good nutrition that they consider it essential. Well justified enthusiasm for the Mediterranean diet can lead to guidance implying it is the only right way to eat for health, and that olive oil is an essential part of an optimal diet. That's excessive in the other direction. The Tsimane don't consume olive oil, and have perhaps the world's most pristine coronary arteries. The traditional Okinawan diet is low in total fat, and olive oil free, but associated with the same great bounty of years in life, life in years as the Mediterranean diet. So, too, is the low-fat vegan diet among the Seventh Day Adventists.

My view is, predictably perhaps, in between. I am convinced a diet does not require olive oil (or one of the rarefied, rival oils) to be optimal; and equally convinced that an optimal diet certainly allows for good olive oil and may benefit from it. There is, obviously, more than one way to eat badly; there is more than one way to eat well, too. The health effects of virtually any food will depend on its specific preparation; the dose; what it is replacing; and its situation in the balance of the overall diet.

Olive oil in general is exceptionally high in healthful monounsaturated fat (oleic acid), and low in omega-6 linoleic acid (we are prone to a relative excess of omega-6 fats, and there may be potential harms linked to that, at least relative to an optimally balanced diet). The variety that figures in traditional diets, that is widely regarded as most delicious, and to which health benefits are reliably attached is “extra virgin.” This refers to oil pressed from freshly picked olives, under cool temperatures, without the use of any chemicals. Extra virgin olive oil preserves not only the fatty acids native to the olive, but antioxidant nutrients as well.

Heat when cooking can degrade an oil no matter its pristine state when bottled. Olive oil has moderate heat tolerance. It holds up perfectly well for sautéing, but not for deep frying. Peanut oil and avocado oil are among the most healthful choices best able to stand the intense heat of a deep fryer. Such considerations argue for a small portfolio of options rather than relying on any one oil for all dietary duties.

In my view, then, an optimal diet does not require good olive oil, but certainly allows for it, and might be enhanced by it. I happen to love it, particularly the spectacular preparations to which I have been introduced by true experts. I am also a beneficiary of my wife's fabulous cooking, in which well-chosen olive oils, native to her Mediterranean upbringing, feature prominently and often.

Diet is of profound importance to health, leaving all of us who care about the length of our lives and the quality of our health with variants on the theme of wholesome foods, mostly plants, in sensible combinations from which to choose, but no alternative to that basic theme. Diet is also of profound importance to pleasure, leaving us all to choose the dietary variant that lets us love the foods that love us back. Dietary pattern is directly linked to diverse environmental impacts as well, in which context the relative sustainability of olive oil production is another important consideration.

I choose an optimal dietary variant that allows for this time-honored delight because I want pleasure as well as health from food, and fine olive oil contributes to both. In your kitchen, that choice is entirely up to you.

David L. Katz, MD, FACP, MPH, FACPM, is an internationally renowned authority on nutrition, weight management, and the prevention of chronic disease, and an internationally recognized leader in integrative medicine and patient-centered care. He is a board certified specialist in both Internal Medicine, and Preventive Medicine/Public Health, and Associate Professor (adjunct) in Public Health Practice at the Yale University School of Medicine. He is the Director and founder (1998) of Yale University's Prevention Research Center; Director and founder of the Integrative Medicine Center at Griffin Hospital (2000) in Derby, Conn.; founder and president of the non-profit Turn the Tide Foundation; and formerly the Director of Medical Studies in Public Health at the Yale School of Medicine for eight years. This post originally appeared on his Linked In page.