Not even our doctors. Most of them get about an hour of instruction in medical school. Of course, that’s a lot more than most of us get.
Nutrition interests me a lot because our knowledge of it is changing so fast. I remember when a doctor at the VA Medical Clinic in Santa Barbara, California, diagnosed my diabetes in 1994. The nutritionist there had me keep a food log. She circled anything that I ate that had much fat in it. Any type of fat. We know now that there are good fats – monounsaturated and polyunsaturated fats – and bad fats – saturated and trans fats.
We know less about antioxidants. We had assumed that Vitamin C, Vitamin E, and beta-carotene would protect us against oxidative stress-related diseases. I was stunned a couple of years ago when one of my favorite doctors, Steven Bratman, wrote me that, “There is not a single example of an antioxidant that has been thoroughly tested and proven to have health value by virtue of being an antioxidant. Quite the contrary. The largest double-blind studies in history were performed on the two likeliest suspects, beta carotene and alpha tocopherol, and failed to find benefit.”
I wrote several times about the importance of the oxygen reactivity absorbance capacity (ORAC) of foods, which quantifies their antioxidant capacity. Until now this was the most important work about antioxidants in foods.
But now The American Journal of Clinical Nutrition has a huge study analyzing the antioxidants in 1120 foods that we eat in the United States. Only the abstract is available free online, but one of my favorite Certified Diabetes Educators, Karen LaVine, sent me the whole study. It takes 41 pages of the journal.
Like Dr. Bratman’s observation, this new study recognizes that large studies of Vitamin E and beta carotene don’t show that they make us more healthy. That’s strange, because many cell culture and experimental animal studies, as well as observational studies seem to show that antioxidants from fruit and vegetables reduce oxidative damage. Maybe that’s because these are only two of hundreds, if not thousands, of antioxidants in foods and they may have to work together in our bodies as they do in plants. We’re still trying to find out.
The new study ranks individual foods and food categories. The food categories with the highest antioxidant content are spices and herbs, nuts and seeds, chocolate and sweets, vegetables and vegetable products, ready-to-eat cereals, desserts and cakes, and berries and berry products.
The food categories that ranked lowest in antioxidant contents are fats and oils; meat, meat products, and substitutes; poultry and poultry products; fish and seafood; and egg and egg dishes.
Among the 50 foods highest in antioxidants, 13 are spices, 8 are based on fruit and vegetables, 5 are berries, 5 are chocolate-based, 5 are breakfast cereals, and 4 are nuts and seeds. Many people will be pleased that red wine and coffee are in the top 50. This gives more credence to the so-called French paradox and many recent studies of the benefits of coffee.
Serving size is important, particularly because spice is the food category highest in antioxidants, and, of course, we eat a lot less spice than we do fruit and vegetables. Still, one spice ranks in the top 10 foods in antioxidants per serving size. The top ten per serving size are: blackberries, walnuts, strawberries, artichokes, cranberries, coffee, raspberries, pecans, blueberries, and ground cloves.
I love to spice up my food and have written to recommend that you “Spice Up Your Life”. But right now I don’t have a single clove at home. You can be sure that they are now on my shopping list. I will certainly add ground cloves the next time I make curry or a stewed fruit, as my old copy of The Joy of Cooking recommends.
The study makes a special point of highlighting the antioxidant benefits of walnuts. It concludes that the combination of lots of antioxidants and its great polyunsaturated fatty acid content may be what makes walnuts so healthy for us.
The authors conclude that their “preliminary studies” suggest a beneficial health effect of consuming plants rich in antioxidants. Still, they say, “much more research is needed” and that “the antioxidant food table can…not be used for dietary recommendations at the present stage.”
But it’s my life now. I can’t wait for researchers to come to final conclusions about what foods – if any – are good for us to eat.
So, I’m taking the results of this study quite seriously. Besides, many of the foods ranked best in this study are those that I eat the most.