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I keep getting questions about saturated fat.  Does it really pose a health risk?  If so, how serious a risk?  And isn’t eating real food OK even if it contains saturated fat?  Good questions.  Here are a couple of recent examples:

Reader #1: I think that the idea that saturated fats in meat and dairy are unhealthful is errant, based on correlative – not causative – scientific studies…I propose that instead of demonizing one nutrient over another, we favor whole, high-quality foods of both animal and plant origin…designed by nature (and thousands of years of trial and error) to meet the needs of their respective populations. What do you say?

Reader #2: I wonder how the government can be so focused on low-fat milk. Is that really such a huge problem? Isn’t the bigger problem that the state of NY is telling people pretzels make a healthy snack? Isn’t it soda and cheese doodles and eating every dinner from a box that is the problem? Whole milk, really? I’d appreciate your clarity on this… we are full fat milk and cheese people, and all of this perplexes me.

I can understand why anyone might be confused about saturated fat.  Food fats are complicated and it helps to be a biochemist (as I once was) to sort out the issues related to degree of saturation and whether the omegas are 3, 6, or 9 (I explain all this in the chapter on fats and in an appendix to What to Eat).

And yes, the science is complex and sometimes seems contradictory but scientific committees for the past 50 years have concluded one after another that substituting other kinds of fatty acids for saturated fatty acids would reduce levels of blood cholesterol and the risk for coronary heart disease.

And no, those scientists cannot have all be delusional or paid off by the meat or dairy industries.  They—like scientists today—mostly call the science the way they see it.

What makes the research especially hard to sort out is that all food fats—no exceptions—are mixtures of saturated, unsaturated, and polyunsaturated fatty acids (just the proportions differ), that some saturated fatty acids raise blood cholesterol levels more than others do, and that one kind—stearic acid—seems neutral with respect to blood cholesterol.

But overall, the vast majority of expert committees typically conclude that we would reduce our heart disease risks if we kept intake of saturated fat below 10% of calories, and preferably at or below 7%.   On average, Americans consume 11-12% of calories from saturated fat, which doesn’t sound too far off but the average means that many people consume much more.

As is often the case with studies of single nutrients, research sometimes comes to different conclusions.  Several studies—all quite well done—have appeared just in the last year or so.

One of these is a meta-analysis (a review of multiple studies). It concludes:

…there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of CHD [coronary heart disease] or CVD [cardiovascular disease]. More data are needed to elucidate whether CVD risks are likely to be influenced by the specific nutrients used to replace saturated fat [my emphasis].

What saturated fat gets replaced with is the subject of three other well conducted studies that come to a different—the mainstream—conclusion.  One, another recent meta-analysis, confirms decades of previous observations (sorry about the annoying abbreviations):

These findings provide evidence that consuming PUFA [polyunsaturated fatty acids] in place of SFA [saturated fatty acids] reduces CHD events in RCTs [randomized clinical trials]. This suggests that rather than trying to lower PUFA consumption, a shift toward greater population PUFA consumption in place of SFA would significantly reduce rates of CHD.

Translation: replacing saturated fats with polyunsaturated fats would be healthier.

Another meta-analysis comes to the same conclusion:

The associations suggest that replacing SFAs with PUFAs rather than MUFAs [monounsaturated fatty acids] or carbohydrates prevents CHD over a wide range of intakes.

A very recent consensus statement concludes:

the evidence from epidemiologic, clinical, and mechanistic studies is consistent in finding that the risk of CHD is reduced when SFAs are replaced with polyunsaturated fatty acids (PUFAs). In populations who consume a Western diet, the replacement of 1% of energy from SFAs with PUFAs lowers LDL cholesterol [the “bad” kind] and is likely to produce a reduction in CHD incidence of ≥2–3%. No clear benefit of substituting carbohydrates for SFAs has been shown, although there might be a benefit if the carbohydrate is unrefined and has a low glycemic index.

The advisory committee to the 2010 Dietary Guidelines for Americans reviewed this and other research relating saturated fatty acids to heart disease risk and concluded:

Cholesterol-raising SFAs, considered SFA minus stearic acid…down-regulate the low density lipoprotein (LDL) receptor by increasing intracellular cholesterol pools and decreasing LDL cholesterol uptake by the liver.

The committee’s research review addressed the question, “What is the Effect of Saturated Fat Intake on Increased Risk of Cardiovascular Disease or Type 2 Diabetes, Including Effects on Intermediate Markers such as Serum Lipid and Lipoprotein Levels?”  It judged the evidence strong

that intake of dietary SFA is positively associated with intermediate markers and end point health outcomes for two distinct metabolic pathways:

1) increased serum total and LDL cholesterol and increased risk of CVD and

2) increased markers of insulin resistance and increased risk of T2D [type-2 diabetes]. Conversely, decreased SFA intake improves measures of both CVD and T2D risk.

The evidence shows that 5 percent energy decrease in SFA, replaced by MUFA or PUFA, decreases risk of CVD and T2D in healthy adults and improves insulin responsiveness in insulin resistant and T2D individuals.

How much saturated fat might increase the risk of heart disease or type-2 diabetes depends on how much you eat as well as what you eat.

What to do to reduce your dietary risks for heart disease?  Take a look at the top 15 sources of saturated fats in U.S. diets:

• Regular cheese
• Pizza
• Grain-based desserts (cakes, cookies, pies, pop-tarts, donuts, etc)
• Dairy desserts
• Chicken and chicken mixed dishes (e.g. fingers)
• Sausage, franks, bacon, and ribs
• Burgers
• Mexican mixed dishes
• Beef and beef mixed dishes
• Reduced fat (not skim) milk
• Pasta and pasta dishes
• Whole milk
• Eggs and egg mixed dishes
• Candy
• Butter
• Potato/corn/other chips
• Nuts/seeds and nut/seed mixed dishes
• Fried white potatoes

Explanation: These foods do not necessarily have the most saturated fat.  If the list surprises you, recall that all food fats have some saturated fats.  These foods are leading sources because they contain some saturated fat and many Americans eat them.

It is surely no coincidence that these foods are also among the leading sources of calories in U.S. diets.  The health effects of diets, let me repeat, have to do with quantity as well as quality.

If you do not habitually eat most of the foods on this list, and are not gaining weight, saturated fatty acids are much less likely to be a problem for you.

And just because saturated fats raise the risk of heart disease does not mean they are poisons.   Eat fats.  Just not too much.

 

 

 

Imagine this.  A professional journal, Preventing Chronic Disease: Public Health Research, Practice and Policy (Vol 8, Issue 5, Sep 2011) has published a series of papers on the ethics of childhood obesity interventions. 

It is about time that these kinds of ethical issues are getting focused attention.  Applause for the journal’s editors and authors!

Ethical Issues In Interventions For Childhood Obesity

A92: Protecting Children From Harmful Food Marketing: Options for Local Government to Make a Difference
  Jennifer L. Harris, Samantha K. Graff

A93: Childhood Obesity: A Framework for Policy Approaches and Ethical Considerations
  Rogan Kersh, Donna F. Stroup, Wendell C. Taylor

A94: Childhood Obesity: Issues of Weight Bias
  Reginald L. Washington

A95: Children With Special Health Care Needs: Acknowledging the Dilemma of Difference in Policy Responses to Obesity
  Paula M. Minihan, Aviva Must, Betsy Anderson, Barbara Popper, Beth Dworetzky

A96: Public Policy Versus Individual Rights in Childhood Obesity Interventions: Perspectives From the Arkansas Experience With Act 1220 of 2003
  Martha M. Phillips, Kevin Ryan, James M. Raczynski

A97: A Question of Competing Rights, Priorities, and Principles: A Postscript to the Robert Wood Johnson Foundation Symposium on the Ethics of Childhood Obesity Policy
  Shiriki K. Kumanyika

A98: The Ethical Basis for Promoting Nutritional Health in Public Schools in the United States
  Patricia B. Crawford, Wendi Gosliner, Harvey Kayman

A99: Ethical Family Interventions for Childhood Obesity
  Mandy L. Perryman

A100: Public Policy Versus Individual Rights and Responsibility: An Economist’s Perspective
  Frank J. Chaloupka

A101: State Requirements and Recommendations for School-Based Screenings for Body Mass Index or Body Composition, 2010
  Jennifer Linchey, Kristine A. Madsen

A91: Ethical Concerns Regarding Interventions to Prevent and Control Childhood Obesity
  John Govea

Q. Have you seen this clever project? By the filmmakers of King Corn, comes “Truck Farm,” a movie about the smallest CSA in the biggest city. You can grow food anywhere….

A. Have I seen it? Of course I’ve seen it.

I’m in it.

I joined the CSA and got filmed when they delivered my share.

Cool.

Q. I’ve just been thinking about this in light of the current situation – the worst drought in 60 years. Do you think that there is more awareness of global food security, the global food system and ‘our responsibility’?…I find this a complex issue and I think it is incredibly important we don’t forget it as other news items are prioritized.

A. Your question arrived just as the New York Times put another one of those devastating photographs of a starving child on its front page, this time to illustrate the famine in Somalia.

Like all famines, this one is politically induced.  What’s going on in Somalia these days is a consequences of a lengthy colonial history.  A colleague and I wrote a controversial paper about such issues more than 15 years ago (see Nestle M, Dalton S. Food aid and international hungerr crises: the United States in Somalia. Agriculture and Human Values 1994;11(4):19-27)

At the time, I was struck by how often the history of humanitarian aid repeats itself.  We keep making the same mistakes. 

This is because it seems—and in the case of Somalia is—much easier to deal with the immediate demand for food aid than to address the underlying politics that caused the problem in the first place.   

But if we don’t deal with the underlying politics, the same tragedies occur again and again.  

More awareness? I don’t see it happening—just increasing feelings of helplessness in the face of so much human misery. 

What to do?  I have no answers.  Somalia is too dangerous for amateurs. 

Readers: Thoughts?  Suggestions for action?

I’ve been rounding up information about the Cargill recall of ground turkey contaminated with Salmonella Heidelberg.  William Neuman at the New York Times related the story on August 3. Same old same old.

Cargill is a huge company with, as Bill Marler counts them, a long history of food safety problems.  Did Cargill not bother to test for pathogens?   As I explain in my book Safe Food: The Politics of Food Safety, no meat company wants to test for pathogens.  If they found pathogens, they would have to recall the products.

And where was the USDA in all of this?  Best not to ask.

The USDA was testing.  The testing found Salmonella.  The USDA did nothing.

According to the Wall Street Journal,

Federal officials said they turned up a dangerous form of salmonella at a Cargill Inc. turkey plant last year, and then four times this year at stores selling the Cargill turkey, but didn’t move for a recall until an outbreak killed one person and sickened 77 others.

How come?

Food-safety specialists said the delay reflected a gap in federal rules that don’t treat salmonella as a poisonous contaminant, even if inspectors find antibiotic-resistant forms such as the Heidelberg strain implicated in the latest outbreak.

But CDC investigations show that turkey-related illnesses have been reported for months.  Despite the reports, the USDA took its own sweet time insisting on a recall.

The rationale for the delay is—get this—the USDA believes it does not have the authority to order recalls for any contaminant except E. coli O157:H7.  It has no authority to recall meat contaminated with Salmonella or other toxic forms of E. coli.

Or at least that’s how USDA interprets the legal situation (for the history of all this, see Bill Marler’s summary.

One reason for the USDA’s foot-dragging must surely be pressure from the meat industry which wants as little testing as possible and preferably none.  The meat industry would rather leave it up to you to cook your food safely.

According to a report by Elizabeth Weise in USA Today,

The reasons these bugs aren’t currently regulated are a mix of politics, money and plain biology — the bacteria are constantly evolving and turning up in new and nastier forms, making writing rules about them a bit of a nightmare. For example, the German E. coli variant that sickened more than 4,075 in Europe and killed 50…wasn’t known before this spring.

The meat industry takes advantage of this situation and argues:

“We don’t have a true baseline determining the prevalence of these organisms in the beef supply,” says Betsy Booren of the American Meat Institute (AMI) Foundation, the research arm of AMI. Without knowing how common they are, it’s impossible to say whether they should be considered adulterants, she says.

What they seem to be saying is that meat always has bacteria on it.  And just because these particular bacteria can kill people doesn’t mean the industry is responsible if anyone gets sick.  But shouldn’t the industry be doing a better job?

In Food Safety News, Michele Simon has a terrific analysis of the safety loopholes that allow this absurd situation to continue:

How did the meat industry get so powerful that it can keep USDA from doing its job? Now, instead of preventing illnesses from occurring by requiring testing with teeth, we have USDA regulations that are so lax they allow almost half the samples tested at ground turkey plants to be contaminated with Salmonella — a pretty easy standard to meet. And one that allowed this outbreak to occur.

I keep asking: how much worse does it have to get before Congress does something about ensuring safe food.  Cargill’s inability to protect the public from unsafe meat is reason alone to create a single food safety system that unites the functions of USDA and FDA.

If Congress isn’t ready to take that step, it could at least give USDA the power to act and the FDA the funding it needs to do its job.

Q.  I would love to hear what you think about hydroponic food. My instincts tell me that organic soil is full of life and traces of nutrients and elements we don’t fully understand and here we have another frankenfood that is scientifically derived.

A.  Frankenfood is too strong but I’m basically with you on this one.  I don’t get hydroponics.  Obviously scientists have figured out enough about plant nutrient requirements to keep them alive in water and nutrient broth but what’s the point?  Soil works really well and is bound to contain substances we don’t even know about.  These may even influence taste.

Chefs say even the best of hydroponic vegetables, according to a recent New York Times article, are not considered serious replacements for field-grown lettuces because they can’t reproduce the flavor.

My suspicion?  People who like hydroponics don’t like getting their hands dirty (but isn’t that half the fun?).

 

I’ve just turned in the copy-edited manuscript of Why Calories Count: From Science to Politics (pub date March 2012) and now have time to catch up on some questions:

Q. I was recently given to read a book titled “The China Study” which is based on research conducted in 1970’s in China by Dr. Colin Campbell. His main conclusion is that eating dairy and meat causes cancer. His resolution is that a plant-based diet (i.e. vegan) is the (only?) healthy diet for humans. This book has made strong enough of a point to convince several of my friends to “convert” to a vegan diet in order to save their health. Could you share some comments on the validity of the research and conclusions this book presents with regards to detrimental effects of dairy and meat on human health?

A. Campbell makes a forceful argument based on his interpretation of the research and on case studies of people whose diseases resolved when they became vegans. And yes I’ve seen Dr. Campbell’s new movie, Forks over Knives. The first half is a terrific introduction to how the current food environment promotes unhealthy eating.  The second half promotes Dr. Campbell’s ideas about the hazards of meat and dairy foods.

Whether you agree with these ideas or not, the film is well done and worth a look.

Some scientists, however, interpret the research as demonstrating that people are healthier when they eat dairy foods.  For example, the enormous consensus report on diet and cancer risk from the American Institute for Cancer Research and the World Cancer Research Fund concluded in 2007 that eating lots of red meat and processed meat is convincingly associated with an increased risk of colorectal cancer (but no others).

On the other hand, they found dairy foods to be associated with a decrease in the risk of colorectal cancer.  They found limited and less convincing evidence that dairy foods might decrease the risk of bladder cancer but increase the risk of prostate cancer.

How to make sense of this?  These are two food groups in the diets of people who consume many kinds of foods and who do many things that might increase or decrease cancer risk.  Given this complexity, one food or food group seems unlikely to have that much influence on cancer when considered in the context of everything else people eat and do.

Nutrition research, as I am fond of saying, is difficult to do and requires interpretation. Intelligent people can interpret the studies differently depending on their point of view.

The new Dietary Guidelines say to cut down on saturated fats. Those are most plentiful in meat and dairy foods (plant foods have them, but in smaller amounts). Pretty much everyone agrees that plant-based diets promote health/  But whether they have to be 100% plant-based is highly debatable.

The new USDA MyPlate food guide suggests piling plant foods—fruit, vegetables, and grains—on 75% of your plate so the argument is really about what goes on the remaining 25%, what USDA calls the  “Protein” section. You can put beans in that quarter if you don’t want to eat red meat, poultry, or fish.

Q. I’d love to hear your take on the recent walnut flap [accusations that the FDA now considers walnuts to be drugs].  I suspect walnuts got caught with such offenders as Pom, Froot Loops, and Juicy-Juice, but I’d love to find out what the FDA actually said about this. For some odd reason I don’t believe the article is presenting the whole truth.

A. This is a health claims issue. The FDA is not saying walnuts are drugs. It is saying that Diamond Walnut is claiming walnuts as drugs on package labels. How so?

The labels say the omega-3 fatty acids in walnuts may help lower cholesterol; protect against heart disease, stroke and some cancers (e.g. breast cancer); inhibit tumor growth; ease arthritis and other inflammatory diseases; and even fight depression and other mental illnesses. These are disease claims for which the FDA requires scientific substantiation.

The company’s petition did not provide that substantiation so the FDA issued a warning letter. In general, you should be skeptical any time you see a nutritional factor advertised for its ability to prevent or treat such a broad range of problems.

Q. A question about sugar and how it is counted: My books say: 4 g = 1 teaspoon = 15 calories. My Illy Caffe says 10 g of sugar, but 50 calories. Ingredients: coffee, sugar, potassium bicarbonate, potassium citrate. If the drink is 50 calories, shouldn’t it say 12 g or more for the sugar listing?

A. Sugar should be the only ingredient that has calories in this coffee but I’ve seen calorie lists that say 5 calories per gram for sugars. Food companies have some leeway in the way they compute calories. Illy may be using a method that gives 5 rather than 4. But the difference between 40 and 50 is hardly measurable and I wouldn’t worry about amounts this small, annoying as imprecise figures may seem.

My monthly (first Sunday) Food Matters column is in answer to a question about the deeper meaning of the fuss over McDonald’s “healthier” Happy Meals.

Q: Wouldn’t it be the best form of activism to encourage people to buy McDonald’s slightly-less-bad-for-you Happy Meals? If the new formulation flops, do you really think McDonald’s will take more baby steps in the same direction? Aren’t you letting perfect be the enemy of the good?

A: The question, for those of you ignoring national media, refers to McDonald’s announcement that it plans to restructure its Happy Meals for kids by adding fruit, downsizing the fries and reducing calories by 20 percent and sodium by 15 percent.

Skeptic that I am, I took a look at McDonald’s lengthy press release. The company does not claim to be making healthier changes. It says it is offering customers improved nutrition choices. This is something quite different.

At issue is the default meal – the one that gets handed to you without your having to ask for anything. Plenty of research shows that although customers can request other options, most take the default. So the default is what counts.

McDonald’s says its new default will include a quarter cup of apple slices (how many slices can that be?), less sodium and 1 ounce less of french fries (thereby reducing calories and fat). These are steps in the right direction, but tiny baby steps.

The rest is up to you: hamburger, cheeseburger or McNuggets.

As for beverage, the press release says, “McDonald’s will automatically include produce or a low-fat dairy option in every Happy Meal.”

This sounds great. “Automatically” makes me think the default Happy Meal will come with low-fat milk. No such luck. It’s up to you to choose from soda or low-fat chocolate or plain milk.

Want something healthy? You have to ask for it. And the meal still comes with a toy, although the meal isn’t healthy enough to qualify for a toy under the San Francisco’s nutrition standards, which are scheduled to go into effect in December.

The McNuggets meal meets the San Francisco standard for sodium, overall calories and for saturated fat – if you choose low-fat white milk. It fails the other criteria. Fat provides about 40 percent of the calories (the standard is 35 percent), and fruit misses the mark by 50 percent. The hamburger and cheeseburger meals fare worse. And even if french fries count as a vegetable, they don’t reach the three-quarter-cup standard. Sodas, of course, have too much sugar.

No toy for you, San Francisco kids.

So let’s get back to the underlying question: Isn’t perfect the enemy of the good? Aren’t baby steps like these in the right direction and, therefore, deserving of support?

I don’t think so. McDonald’s proposed changes are a reason to ask a different question: Is a better-for-you Happy Meal a good choice? Wouldn’t your child be better off eating something healthy, not just slightly healthier?

Couldn’t McDonald’s, the largest fast-food maker in the world, come up with something genuinely healthy that also tastes good?

“Better for you” is a marketing ploy, and McDonald’s must need help. Although its annual sales are $24 billion from its 14,000 outlets in the United States, Happy Meals have not been doing well.

Business analysts attribute declining sales since 2003 to the unsophisticated toys. Toys are the only reason kids want Happy Meals, but more parents are ordering adult meals and splitting them with the kids. But what if Happy Meals appear healthier?

Let’s be clear: McDonald’s is not a social service agency. It is a business. Its business interests come first. This means selling more food to more people more often, viewing food choice exclusively as a matter of personal responsibility and pretending that the company’s $1.3 billion annual marketing expenditure has no effect on consumer choice.

I suspect McDonald’s actions are attempts to appease Michelle Obama’s healthy eating campaign and perhaps to attract health-minded families to its outlets.

But surely the changes are also part of a calculated public relations effort to discourage other communities from enacting nutrition standards like those in San Francisco.

What McDonald’s actions make clear is the need for federal action to make it easier for people to make healthier choices for their kids. This means putting some curbs on marketing below-standard foods to kids and insisting that default kids menus be healthy.

If McDonald’s were serious about promoting kids’ health, it would offer default Happy Meals that meet San Francisco’s nutrition standards and advertise them to the hilt. Until the company does that, I’m reserving applause.

Marion Nestle is the author of “Food Politics,” among other books, and is a professor in the nutrition, food studies and public health department at New York University. E-mail her at food@sfchronicle.com.

This article appeared on page G – 4 of the San Francisco Chronicle