I can’t believe the number of times I have been asked that question but it has just come up again in the context of recent complaints about the health and environmental hazards of eating meat.  So here, once again, is my nutrition academic’s take on the nutritional implications of vegetarian diets.

Full disclosure: I eat meat.  Humans are omnivores and I am one nutritionist who fully subscribes to basic, if banal, principles of healthful diets: variety, balance, and moderation. As I explain in my book, What to Eat, if you eat a variety of foods within and among groups – meat, dairy, fruit, vegetables, and grains – you don’t have to worry about nutritional details.  As long as calories are adequate and the foods are relatively unprocessed, the different kinds of foods complement each other’s nutrient contents and provide everything that is needed in reasonable amounts and proportions.

With that said, it is not necessary to eat meat.  Meat is not an essential nutrient.  I can think of plenty of advantages to eating no meat, eating less meat, or eating meat produced in ways that are far better for the health of animals, people, and the planet.

Why anyone would question the benefits of eating vegetarian diets, or diets that are largely vegetarian is beyond me.   People who eat vegetarian diets are usually healthier – sometimes a lot healthier – than people who eat meat.

But before getting into all this, there is the pesky problem of definition.  What, exactly, is a vegetarian?  As it happens, people who call themselves vegetarians eat many kinds of diets.  The least restrictive vegetarians do not eat beef but occasionally eat pork or lamb.  Next come the groups that eat no red meats, or restrict poultry, dairy, fish, or eggs.  The most restrictive are vegans who eat no foods of animal origin at all.

Nutritional implications depend on the degree of restriction.  The least restrictive diets, those that exclude meat but include fish, milk, or eggs, raise no nutritional issues whatsoever.  People who eat such diets are likely to have a lower risk of heart disease and certain cancers than the average meat-eating American, and a risk of osteoporosis no higher.

Only the most restrictive vegetarian diets raise nutritional concerns.  Vegans, who eat no foods of animal origin, need to do three things:

• Find an alternative source for vitamin B₁₂ (supplements or fortified foods).
• Eat enough calories to maintain a good weight.
• Eat a variety of grains and beans to get enough protein.

Vitamin B₁₂ is found only in foods of animal origin – meat, dairy, eggs, or fish.  With this one exception, fruits, vegetables, and grains provide plenty of the other vitamins and minerals.  Vegans who obtain enough calories from varied plant food sources should be taking care of those nutrients as well as protein.

On the protein question: Foods from animals are higher in protein than those from plants.  Their proteins are of somewhat better quality, meaning that they more closely resemble human proteins.  If calories are adequate, protein is rarely a problem.   Protein is hardly lacking among Americans.  The protein requirement is about half a gram for each pound of body weight, which works out to 55 grams for a 120-pound woman and 65 grams or so for a 180-pound man. On surveys, women report eating a daily average of 70 grams of protein, and men 100 grams, and these amounts are likely to be underestimates.  Even vegans get more than enough protein from grains, beans, and vegetables as long as they get enough calories.

In relatively unprocessed foods, protein is closely linked to calories.  Diets with enough calories usually contain enough protein unless the diet is unusually restrictive or includes a lot of junk food.  Think about it: entire civilizations – in ancient Egypt, China, and Mexico, for example – were based on wheat, rice, beans, or corn as sources of protein.   We used to think that vegetarians had to be careful to combine plant foods (beans and corn, for example) to get enough protein but we know now that variety and calories take care of it.

Developing countries are another matter.  In places where food is scarce, children thrive better when they are fed a little meat (or dairy, fish, or eggs) along with whatever else they are eating, but a richer plant-based diet also works well.

That brings us to children.  Is it OK to feed vegetarian diets to kids?  This too depends on what is meant by “vegetarian.”  If the diet restricts just beef or red meat, it poses no problems.  Dairy foods, fish, and eggs are adequate substitutes.  And keeping sodas and junk foods to a minimum is always a good idea.

Vegan diets are another matter and I can think of plenty of reasons why they are controversial for children.  Supplements can take care of kids’ needs for vitamin B₁₂ and other nutrients, but calories can be a serious problem.  Children sometimes have a hard time when they have to get all their food energy from vegetables, grains, or beans.  I advise vegan parents to pay close attention to calories, to make liberal use of olive oil and nut butters, to make sure plenty of beans, grains, and potatoes are available, and to monitor their children’s weight in comparison to lines on standard growth charts.

Except for the most restrictive diets, I wouldn’t worry at all about vegetarian diets for adults or for kids.  They have plenty of what’s good for health and a lot less of what is not so good.  The health advantages can be impressive.    So eat your veggies!

In his thoughtful (and lengthy) obituary of Claude Lévi-Strauss, Edward Rothstein describes the French anthropologist as a profoundly influential and powerful thinker, an intellectual giant of the 20th century, and a scientist whose analyses of the cultural significance of myths “challenge the reader with their complex interweaving of theme and detail.”  Lévi-Strauss did all this, and more.

But I think of Lévi-Strauss as the inventor of Food Studies before the field existed.  If present-day food academics do not always acknowledge his groundbreaking use of food and foodways to explore how “primitive” societies make sense of their worlds – or require students to read his books in their courses – it is surely because “challenge” falls so far short of conveying the stunning impenetrability of his writing.

Here, for example, is one of the more lucid passages from the chapter on culinary anthropology in The Origin of Table Manners (1968).  This is from the University of Chicago 1990 edition, page 487 (translated by John and Doreen Weightman):

Within the basic triangle formed by the categories of the raw, the cooked and the rotten, we have, then, inserted two terms, the roast and the boiled, which, in most cases, can be placed, one in the vicinity of the raw and the other in the vicinity of the rotten.  Still missing, however, is a third term, illustrating the concrete modalities of the form of cooking which most resembles the abstract category of the cooked.  This modality, I suggest, is smoking, which, like roasting, implies a non-mediated operation (involving neither a receptacle nor water), but which, unlike roasting but in the manner of boiling, is a slow form of cooking, and so both thorough and steady.

Even so, Food Studies students and scholars are much in his debt.

Kellogg’s says it will phase out boxes of Cocoa and other Rice Krispies cereals with the IMMUNITY claim on them.

Withdrawn, November 4, 2009

The Immunity claim falls into an FDA regulatory grey area.  It is a structure-function claim, meaning that the product is supposed to support a structure or function of the human body – not treat or cure a disease. If Cocoa Krispies were a dietary supplement, the claim would be completely legal because Congress authorized structure-function claims for supplements when it passed the Dietary Supplement Health and Education Act of 1994.

Over the years, food makers complained that if supplements could use such claims, they could too.  At first, the FDA issued warning letters to food companies using structure-function claims.  It stopped after the courts ruled that food companies could make claims for the health benefits of their products on First Amendment grounds.

Now FDA says structure-function claims are OK to use as long as they are truthful and not misleading.  Misleading, of course, is in the eye of the beholder.  Evidently, the San Francisco city attorney thought this claim was misleading and demanded the evidence to back it up.  USA Today wrote about this on the front page (I’m quoted in it).

Wisely, Kellogg’s is going to find another design for its Rice Krispies packages.  Consider this particular box a collector’s item.

The lesson: In the absence of FDA action, food marketing is allowed to run rampant, and city and state attorneys are doing the FDA’s job.  Good for them.  And let’s hear cheers for the power of the press.

In what the functional food industry refers to as a “bad day at the office,” the European Food Standards Agency (EFSA) rejected hundreds of health claims, particularly those for probiotics.  More recently, it rejected a claim that glucosamine prevents cartilege degeneration.  Hard as it may be for the food and supplement industries to believe, EFSA just can’t find scientific evidence to support those claims.

A representative of the company that applied for the glucosamine claims says his company now anticipates a loss in product sales, and complains that it had “invested quite heavily in this submission, in terms of effort and financial outlay.”

Too bad.

Why can’t they come up with the science to support those claims? For one thing, who would want to do the research?  Danone and Yakult have just announced two $50,000 grants to study probiotics.  This won’t go far and the sponsorship is an almost certain guarantee that the results will be just what the companies paid for.

Independent research is much more complicated.  Consider folic acid, for example.  The latest clinical trial of folic acid and colon cancer went to a lot of trouble to prove that folic acid supplements are harmless.  In most people, they have no effect on colon cancer, neither benefit nor risk.  Among the few people who had unusually low levels of the vitamin in their blood, the supplements appeared to have some protective effect.  You can interpret results like this either as evidence for no benefit or as evidence that folic acid supplements might benefit some people under some circumstances.

And that brings us to supplements again.  A trade association for supplement manufacturers says:

While it cannot be denied the food and supplement industry has entertained its fair share of cowboys, our concern is that the [EFSA] regulation goes so far as to throw the baby out with the bathwater. At the very point in time when consumers need most information to help them make the right food and supplement choices to help them offset largely preventable chronic diseases, we see the industry being gagged.

“Cowboys” are indeed a problem, and one well known to the American supplement industry. Says the head of the Council for Responsible Nutrition, the euphemistically named supplement trade association:

Fifteen years ago, our biggest threat was an over-reaching FDA….More recently, the problem has been an FDA that’s under funded and lacks the political will to do what it needs to do. And as a result today, many of the problems that burden the dietary supplement industry are ones that come from within the industry itself from that lack of oversight….Companies… intentionally – or inadvertently – put prescription drugs or anabolic steroids into their products and call them dietary supplements; products that just don’t do what they claim.  Also some companies practice economically motivated adulteration, passing off shoddy products as something more than they are … and ignore the new GMP requirements in hopes that they will fall under the radar screen.

Perhaps in response, the Boston Globe says we should repeal the 1994 law that deregulated dietary supplements and give the FDA some regulatory teeth.  Good idea.

Please forgive my endless repetition of this mantra: health claims are about marketing, not health.

Here’s a good reason why food manufacturers don’t want to test for harmful chemicals.  If you test, you might find something you don’t want to.

Consumer Reports did just that.  It tested a bunch of canned juices, soups, tuna, and green beans and found bisphenol A (BPA) in almost all of them — even the ones labeled organic or bisphenol A-free.

BPA, you may recall, is a chemical in polycarbonate plastics that acts as an endocrine disruptor.  How harmful is it?  Debate rages.  These new data will add to the debate.

CR says it found the highest levels of BPA in some samples of canned green beans and canned soups:

• Canned Del Monte Fresh Cut Green Beans Blue Lake had the highest amount of BPA for a single sample in Consumer Reports tests, with levels ranging from 35.9 parts per billon (ppb) to 191 ppb. Progresso Vegetable Soup BPA levels ranged from 67 to 134 ppb. Campbell’s Condensed Chicken Noodle Soup had BPA levels ranging from 54.5 to 102 ppb.

• Average amounts in tested products varied widely. In most items tested, such as canned corn, chili, tomato sauce, and corned beef, BPA levels ranged from trace amounts to about 32 ppb.

Because it was particularly concerned about BPA exposure for infants and young children, it tested samples of infant formula and apple juice.  It found:

• Similac liquid concentrate in a can averaged 9 ppb of BPA, but there was no measurable level in the powdered version.

• Nestlé Juicy Juice in a can averaged 9.7 ppb of BPA, but there were no measurable levels in the samples of the same product packaged in juice boxes.

Although the BPA in Nestlé Juicy Juice averaged 9 ppb, this was not so high, but children consume a lot of juice so this levels worries the testers.

While waiting for the experts to decide just how bad a problem BPA might be for adults and children, Consumer Reports recommends reducing the risk:

* Choose fresh food whenever possible.

* Consider alternatives to canned food, beverages, juices, and infant formula.

* Use glass containers when heating food in microwave ovens.

I would add to this: urge the FDA to finish up its scientific review right away.  It would be good to know more about just how harmful BPA is, and at what levels.

Update, November 4: I love the industry response to this report: “The use of bisphenol A (BPA) in can linings is both safe and vital for food protection.”

Update, November 9: Thanks to Jill Richardson of La Vida Locavore for telling me about her investigations into lobbying against restrictions on BPA (she also posted a summary as a comment here, but her site gives many more of the political details).  The plastics and related industries must be really worried.  They have reason to be worried.  There hasn’t been much reassuring news about BPA recently.

If only meat were just a food and not the flash point for concerns about health, climate change, and tax policy.  But it looms large in all such debates.

According to reports, meat is linked not only with a higher rate of cancer but also with type 2 diabetes.   Does this make logical sense?  It could, especially if meat eaters take in more calories and are fatter than non-meat eaters.

We’ve heard so much lately about how farm animals contribute to environmental problems and climate change, but Nicolette Hahn Niman writes in the New York Times of “the carnivore’s dilemma.”  It’s not the animals themselves that contribute to climate change, it’s the industrial methods of raising them that are the problem.  She ought to know.  She and Bill Niman run the free-range ranch in Bolinas, California highlighted in Time magazine last August.

On the other hand, Princeton professor and ethicist Peter Singer argues in the New York Daily News that meat is so bad for health and the environment that it ought to be taxed.

How to deal with all of this?  Push for more humanely and sustainably raised farm animal production, dont’ eat meat if you choose not to, and if you do eat meat, just don’t eat too much of it.

Update, November 4: I forgot to include Jonathan Safran Foer’s piece in the New York Times magazine on why he is against meat.

My latest column in the San Francisco Chronicle deals with an issue I discussed earlier on this blog: the ways in which agricultural and food interests are pushing back against advocates for a healthier and more sustainable food system.

Frank talk about food sometimes quashed

Marion Nestle, Sunday, November 1, 2009

Q: It must take courage to criticize the marketing practices of food companies. Doesn’t it get you into a lot of trouble?

A: Trouble? That depends on how you define it. Some pushback has to be expected as a normal consequence of advocating a food system that promotes better health for all and more sustainable agricultural production.

My latest experience with pushback occurred on World Food Day, Oct. 16. I had been invited by the U.S. Embassy in Rome to give the annual George McGovern lecture at the U.N. Food and Agriculture Organization. After my talk, our new ambassador to U.N. agencies in Rome, Ertharin Cousin, thanked me but told the audience that the opinions they had just heard were mine alone and did not represent those of the U.S. government.

What did I say that required a disclaimer? The point of my talk was to argue that international food issues such as hunger, obesity and food safety must be viewed as problems of society rather than personal choice.

As social problems, they are unlikely to be solvable by technical interventions such as functional foods, commercial weaning foods, irradiation or genetically modified foods. Instead, international food problems require social interventions that address underlying human needs for sustainability, social justice and democracy.

World insecurity

FAO had just released its 2009 report on the state of world food insecurity. Its date revealed how the economic crisis has caused the number of hungry people in the world to increase sharply. Some argue that genetic modification of crops is the only way to increase food productivity and reverse this trend. Whether food biotechnology really can fix world hunger is debatable, but one thing is clear: It is unlikely to create sustainability, social justice or democracy.

We know how to solve world hunger problems: promote breastfeeding, provide clean water and safe food, empower women, educate children, develop community food security, promote agricultural sustainability and ensure political stability. These strategies are social, not technological.

I ended my talk with praise for the Obamas’ leadership in promoting sustainable food production and initiating a new era in American agriculture.

Un-American? Under ordinary circumstances I would have shrugged off the ambassador’s remarks, but these are not ordinary times. I interpret her remarks as evidence that the food movement must be making real progress.

As further evidence, consider what happened to journalist and Berkeley professor Michael Pollan. His “Omnivore’s Dilemma” is high on the reading lists of many universities, yet twice this fall agricultural interests have attempted to force universities to cancel campus speaking invitations.

Pressure over Pollan

Washington State University had already bought 4,000 copies of “Omnivore’s Dilemma” for incoming freshman when a member of its Board of Regents, a wheat grower, objected to the way the book portrays industrial agriculture. The university canceled the reading program and Pollan’s lecture, saying it would cost too much at a time of budget crisis.

Bill Marler, a Seattle lawyer and WSU alumnus, called the university’s bluff by offering to pay the costs. Pollan’s book got distributed. He gave his talk. State agriculture did not collapse.

Much the same thing happened at Cal Poly San Luis Obispo. A local beef rancher, outraged that Pollan had been invited to speak unopposed, threatened to withdraw a promised $500,000 contribution. The rancher’s exchange of letters with Cal Poly’s president is available at links.sfgate.com/ZIMH, and well worth reading by anyone concerned about how industrial agriculture influences public policy.

Pollan offered the university a free lecture or panel with other speakers, but not both. The university chose the panel.

Although the rancher’s argument might appear to be about the value of presenting balanced views to students, universities are supposed to distinguish between academic and commercial interests. As university professors, Pollan and I base our opinions on our education, training, research and professional experience – not on how they might affect an industry. Our job is to teach students to read and think critically so they can form their own opinions about what we and others tell them.

Exerting influence

If our professorial opinions cannot be offered without public disclaimers and insistence on equal time for opposing views, I have to assume that what we are saying must be perceived as influential. If it indeed is influential, I expect even more pushback as the current food movement extends its reach and becomes stronger and more effective.

Trouble? Bring it on.

Thanks to Anulu Mass of the Global Post for telling me about the latest front-of-package foods labeling initiative, this one from Italy.  I’m just back from lecturing in Rome, Milan, and Vicenza, but didn’t get to Sicily which must be why I missed seeing Libera Terra labels on wine, olive oil, pasta, and tomato sauce.  Libera Terra labels guarantee that the foods were produced with no mob connections.  I’m so relieved.

Trick or treat?