Food Politics

I’ve had several requests to comment on the new New York City Board of Education restrictions on what foods parents can bring to school bake sales.  Home-baked goods are forbidden.  Instead, parents may bring fruits and vegetables (fine) or any of 27 commercial packaged snack foods (oops).

This ruling is an example of nutritionism in action – foods reduced to their content of a few selected nutrients.  The Board must think that if a food doesn’t have a Nutrition Facts label, it isn’t worth eating or its nutritional quality can’t be trusted.

This ruling is a perfect example of why we need standards for schools based on food, not nutrients.

Laura Shapiro explains the history of all this beautifully in an interview with the New York Times.

NPR also had plenty to say about parent protests.

If it were up to me, junk food would be out of schools altogether and bake sales and the like restricted to special occasions.  But if forced to choose between packaged snacks and home-baked cupcakes, I’d throw out the commercial snacks, and put some restrictions on the size and frequency of items at bake sales, but otherwise choose home-cooking every time.

I can’t resist dealing with the questions just asked by Elliot and Johannes.  From Elliot:

A meta-analysis of prospective epidemiologic studies showed that there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of coronary heart disease or cardiovascular disease (see: American Journal of Clinical Nutrition, January 13, 2010)…[but] in his book, Good Calories Bad Calories, Gary Taubes clearly attributes most of our chronic disease problems — including heart disease — to carbohydrates (see page 454).  In contrast, Colin Campbell in his book The China Study (pages 113-133) forcefully argues that animal proteins contribute to CVD.  Yet, Dr. David Katz in his book Nutrition in Clinical Practice (pages 130, 133) asserts that to prevent heart disease, “saturated and trans fat should be restricted to below 7% (or even 5%) of total calories . . . .”  Who’s right?  We badly need your unbiased wisdom on this topic.

Joannes says that according to the Weston A Price Foundation,

it seems as if (naturally-occurring) saturated fats are almost better for you than the unsaturated fats we get fed these days, which mainly consist of rancid oils which more than anything contribute to heart disease, whereas many saturated fats are actually quite beneficial.

OK.  Here’s my “unbiased wisdom” (if such a thing exists).  I like to ask: What do saturated fats, sugars, and animal proteins have in common as factors in the development of heart disease?   Answer: They are all single nutrients.

Recall that nutrition research is difficult to do because diets contain many foods, foods contain many nutrients and other chemicals that affect health, and other behavioral, socioeconomic, and genetic factors influence heart disease.  Studies of single nutrients take these chemicals out of their food, dietary, caloric, and lifestyle contexts and are, therefore, reductive.

Such studies tend to produce ambiguous results that demonstrate small differences, if any.  Small differences create situations ripe for interpretation.  Interpretation depends on the viewpoint of the interpreter.  That is why it helps to know who is doing the interpreting and who sponsored the studies.

Short of that, you would have to read every study cited by these authors and come to your own decision about how to interpret them – a daunting task.

My approach to conflicting research?  I look for points of agreement. The authors cited here do not disagree about the basic principles of healthful diets: variety in food intake, moderation in calories, largely plant-based (although not necessarily exclusively), and minimally processed.  Eat according to those principles and you do not have to worry about nutritional details.

All of that boils down to the advice I propose in What to Eat: eat less, move more, eat plenty of fruits and vegetables, and don’t eat too much junk food.

Let the scientists and their interpreters fight it out over single nutrients.  Eat food and enjoy your dinner.

The terrific food writer and cookbook author, Martha Rose Shulman, gets lots of requests for nutrition information on her recipes.  What do I think about this?  Here’s her interview with me borrowed from Zester Daily (the site has the photos and links to her work):

Add Guesswork and Stir -  By Martha Rose Shulman (24 September 2009)

Many of the people who read my Recipes for Health column on The New York Times website are clamoring for me to include nutritional analyses with the recipes. Today you don’t have to be a nutritionist to add this kind of information. There are lots of computer programs that will calculate it for you. The problem is, none of the data is particularly accurate. So my editors and I resist. We question the value of the numbers and know that they’re too easy to tweak.

I don’t like nutritional data because I’ve always approached healthy eating not as a nutritionist, but as a cook. I’ve devoted my career to preparing delicious food that does no harm – not too caloric, not too fatty, with a focus on plant-based foods – because that’s the way I like to eat.

During my 20s I did toy with the idea of getting a degree in nutrition, but I always preferred the kitchen to the classroom. I audited an Introduction to Nutrition class, but stopped going when we had to memorize molecular formulas. I took biology courses at the University of Texas. My professor surely suspected I wasn’t destined for a future in science when I turned in a term paper composed as an epic poem, rhymed couplets and all, entitled “The Odyssey of my Breakfast.” (He gave me a B+.) Once I hit organic chemistry I dropped out and started teaching vegetarian cooking classes.

Still, I do want my NYTimes.com readers to be happy. So after I’d received several dozen emails asking why I don’t include such data with the recipes in my column, I emailed prominent nutritionist Marion Nestle and asked her what she would recommend if I were to get software to do the breakdowns.

“I don’t know any easy way to do this,” Nestle responded. “All software uses the same USDA database plus information from food companies, and all of it requires interpretation. A big reason has to do with measurement. If you give it even a moment’s thought, you realize that the nutrient contents have to vary with growing location, soil conditions, climate, transportation, and storage, so the amounts given in the database can only be approximations of what you are actually eating, particularly if you are not weighing the exact portions out. The data aren’t meaningless, but they don’t mean nearly as much as people think they do. I always laugh when I see calories listed as anything that doesn’t end with a zero. Measurements of nutrients just aren’t all that precise.”

Nestle directed me to the USDA National Nutrient Database, and I saw her point immediately. After typing in “broccoli,” I was offered 15 choices, including “broccoli, cooked, boiled, drained, with salt;” “broccoli, raw;” “broccoli, flower clusters, raw.” Then I had to indicate an amount, either in grams or cups (how do you measure a cup of broccoli florets?). But my recipes simply call for “1 bunch broccoli, broken into florets.” And how do they know how much salt I use? As often as not, I steam my broccoli — which I understand preserves more nutrients than boiling — but that wasn’t even an option.

I punched in garlic. The garlic cloves in the USDA database weigh 3 grams. I weighed my garlic cloves; the plump ones I like to use weigh 6 to 8 grams, the medium ones about 4 grams. Clearly the technicians at USDA do not come from the Mediterranean.

Nutrient analyses encourages us to see the food that we eat in terms of its carbohydrates, fats, proteins, vitamins and other micro-parts. But “nutritionism” doesn’t lead to better health. Michael Pollan makes this point eloquently in his book “In Defense of Food: An Eater’s Manifesto.” His seven-word maxim says just about all you need to know about a healthy diet: “Eat food. Mostly Plants. Not too much.”

Nestle concurs. “I am opposed to nutritional info,” she told me. “The basis of healthful diets is variety, relatively unprocessed foods, and not eating too much. Variety and processing matter because ‘real’ (relatively unprocessed) foods contain large numbers of required nutrients but in different amounts and proportions. If you vary food intake, you don’t have to worry about individual nutrients because the foods complement each other.”

The emails from my readers continue to arrive on a daily basis, but I have not yet bought any nutrition software. Marion urged me to “resist including nutrient analyses to the bitter end,” and so far, I’m holding firm.

I wouldn’t mind so much if I thought the data were reasonably accurate and could be put into context.  We know from studies using experimental animals that it is extremely difficult to induce nutrient deficiencies in animals that are fed a variety of foods providing sufficient calories.  The best way to avoid nutrient deficiencies is to eat a variety of minimally processed foods.  If you do that, you don’t have to worry about specific nutrients.  Vitamin D may be the one exception.  For that, get outside and expose your skin to some sun.  Even in winter!

I’m in Parma on a speaking trip (to Academia Barilla), it’s my birthday, and here are three nice presents that came in on today’s Google feed (“pet food”): my latest column in the San Francisco Chronicle (“Which is better, food or nutrients?”), a review in the San Francisco Chronicle of Pet Food Politics, and an interview about the new book with Jill Richardson on AlterNet.  Enjoy!