by Marion Nestle

Currently browsing posts about: Dietary-Guidelines

Jun 13 2013

The endless debates about salt: Don’t worry. Eat (real) food

Since 1980, U.S. dietary guidelines have advised eating less sodium (salt is 40% sodium, 60% chloride).  Although sodium is an essential nutrient, most Americans consume way more than they need or is good for them—around 3,400 milligrams a day.

The 2010 guidelines advised healthy people to consume no more than 2,300 mg per day (~6 grams, or 1.5 teaspoons).  They advised even less, 1,500 mg, for people with or at high risk for high blood pressure.  Since blood pressure increases with age in countries with high salt intake, this applies or will apply to just about everyone.  

In 2011, the Institute of Medicine said it was imperative to find effective strategies to lower salt intake.  This means dealing with processed and restaurant foods, because that’s where most of the salt comes from, as can be seen from this list of major food sources

Because consumers have no choice about the amount of salt in processed and restaurant foods, education cannot be enough to achieve salt reduction.  Scientists in Australia have just proved this point.

As I explained to a reporter,

Why anyone would think that nutrition education alone would change behavior is beyond me. By this time everyone should know that to change behavior requires not only education, but a food environment—social, political, economic—that supports and promotes the behavior change.

Most dietary sodium comes from processed foods, restaurant foods, and other pre-prepared foods.  All the label can do is say ‘don’t eat me’ It can’t help with what people can eat.

The easiest and most effective way to help people reduce sodium intake is to require food producers and food preparers to use less of it. Good luck with that. I’m not optimistic, particularly given the conflicting and confusing science. 

Ah yes.  The conflicting science.  The IOM now says that there’s no evidence one way or the other that reducing sodium below 2,300 mg per day, or even to 1,500 per day, does much good, and that low sodium intakes could be harmful (but this too is controversial).

Yes, they could, but as Mark Bittman blogs,    

It may be true that there are no benefits in an ultra-low-salt diet, but almost no one is eating an ultra-low-salt diet. It’s not quite like worrying about whether we get “enough” sugar, but it’s nearly as ridiculous.

And now, as Food Navigator explains, the IOM committee is complaining that its report has been badly misinterpreted.  All they said was:

As to whether we should cut back to 1,500 mg or to 2,300 mg sodium a day, meanwhile, the jury is out, says the IOM, not because consuming 1500 mg/day is dangerous, but because there is just not enough data on the benefits of consuming such low levels to support a firm conclusion.

IOM committee members were so bothered by misleading press accounts that they wrote an op-ed to JAMA to clarify:

Rather than focusing on disagreements about specific targets that currently affect less than 10% of the US population (ie, sodium intake of <2300 mg/d vs <1500 mg/d),  the IOM, AHA, WHO, and DGA are congruent in suggesting that excess sodium intake should be reduced, and this is likely to have significant public health effects. Accomplishing such a reduction will require efforts to decrease sodium in the food environment….

The bottom line, Bittman says (and I enthusiastically agree), is that

Salt intake — like weight, and body mass index — is a convenient baseline for public policy people to talk about. If you focus on eating less salt — and, indeed, less sugar — you will inevitably eat less processed food, fast food, junk food (it’s all the same thing.) If you eat less processed food (etc.) you eat more real food. If you eat more real food, not only are you healthier, but you probably don’t have to pay attention to how much salt you’re eating. Wowie zowie. 

Oct 22 2012

Rest in peace George McGovern

Former Senator (D-SD) George McGovern died yesterday at age 90.

His accomplishments as a Senator and statesmen were legion, many of them strongly connected to food politics.

As I mentioned in 2009 when I gave the state department’s annual George McGovern lecture in Rome, he chaired the Senate Select Committee on Nutrition and Human Needs from 1968-1977.   This committee greatly expanded food assistance programs and then developed the first federal guidelines for chronic disease prevention: Dietary Goals for the U.S.

In Food Politics, I described the work of this strongly bipartisan committee (Bob Dole was its lead Republican member) and how it did so much to improve the lives of women and children living in poverty in the United States, and of poor people throughout the world.

The committee also broke new ground in shifting nutrition education from a focus on eating more of a variety of foods to eating less of foods that increased risks for chronic disease.

What’s shown here is the February 1977 version of this landmark report.  As the result of outraged protests by food producers affected by the “eat less” messages, the committee was forced to tone down its recommendations.  The committee issued a revised report in December that year.

That was the committee’s final act.  Congress disbanded it and McGovern lost his bid for reelection.

McGovern leaves an extraordinary legacy, one unimaginable in this era of partisan politics.

He was far ahead of his time, as this 1977 photo shows.  It is a fitting tribute.

Mar 9 2012

The Lancet on nudging and nagging vs. environmental change

I’m getting caught up on my journal reading and just ran across an editorial from The Lancet, January 21It takes on the UK government’s “personal responsibility” approach to health promotion based on the idea that

gently ‘nudging’ people to change their unhealthy behaviours was the key to public health.

Even the UK government has to admit that the nudge approach isn’t working.  Now it is telling physicians in the National Health Service (NHS) to nag:

use every contact with patients and the public to help them maintain and improve their physical and mental health and wellbeing.

The Lancet asks:

Is this a realistic, sensible, and effective recommendation? We would say not.

Effective, evidenced-based public health measures do not include nudging people into healthy behaviours or getting NHS staff to lecture patients on healthy lifestyles.
They include measures such as raising taxes on cigarettes, alcohol, fatty foods, and sugary drinks, reducing junk food and drink advertising to children, and restricting hours on sale of alcoholic drinks….Focusing on other approaches is foolish.
The nudge and nag approaches need one thing: the firm elbow.
I do enjoy reading The Lancet.  Its editors are so clear about the need for environmental changes to make it easier for people eat better diets and be more active.
Jan 5 2012

The new study of protein and weight gain: calories count!

I was intrigued by the new study from the Pennington Research Center concluding that weight gain depends on calories, not how much protein you eat.

The idea that the protein, fat, or carbohydrate content of your diet matters more to weight than how many calories you eat persists despite much evidence to the contrary.

This study did something impressive.  It measured what people ate, how much they ate, and how much energy they expended under tightly controlled conditions.

This is unusual.  Most studies of weight gain and loss depend on participants’ self reports.

Measuring is much more accurate, as I discuss in my forthcoming book with Malden Nesheim, Why Calories Count: From Science to Politics (out April 1).  If you want calorie balance studies to be accurate, you have to measure and control what goes in and out.  The Pennington is one of the few laboratories in the country that can do this.

Pennington researchers got 25 brave people to agree to be imprisoned in a metabolic ward for the 12 weeks of the study.  The volunteers had to eat nearly 1,000 extra calories a day over and above what they needed to maintain weight.  Their diets contained either 5%, 15%, or 25% of calories from protein.

All of the volunteers gained weight (no surprise), although the low-protein group gained the least.  Most of the weight ended up as body fat.  The medium- and high-protein groups also gained muscle mass.  The low-protein group lost muscle mass.

All of the differences in weight gain among individuals could be accounted for by energy expenditure, either as activity or heat (protein causes higher heat losses).

The Wall Street Journal (January 4) did a terrific summary of the results:

This tells you that low-protein diets cause losses in muscle mass (not a good idea), and that there isn’t much difference between diets containing 15% protein (the usual percentage) and higher levels.

The study also suggests that higher protein diets won’t help you lose weight—unless they also help you cut calories.  That calories matter most in weight gain and loss is consistent with other studies based on measurements, not estimations.

Of course the quality of the diet also matters: it’s easier to cut calories if you are eating plenty of vegetables, fruits, whole grains and a varied diet based largely on relatively unprocessed foods—and it’s harder to gain weight on such diets.

Nov 26 2011

The latest source of dietary advice: The Good Wife

I’m not much of a TV watcher so I missed the episode of The Good Wife in which CBS offered a new version of the food guide icon.

Fortunately, the Minneapolis Star Tribune got permission to reprint it.

According to the Tribune’s account of the episode, “Whiskey Tango Foxtrot,”  a character representing the cheese industry proposes a more dairy-prominent alternative to the USDA’s MyPlate:

As for me, I still miss the 1992 Pyramid, maybe because it did not lend itself to such easy satire (see previous post).

Sep 19 2011

United Nations to consider the effects of food marketing on chronic disease

In what Bloomberg News terms an “epidemic battle,” food companies are doing everything they can to prevent the United Nations from issuing a statement that says anything about how food marketing promotes obesity and related chronic diseases.

The U.N. General Assembly meets in New York on September 19 and 20 to develop a global response to the obesity-related increase in non-communicable, chronic diseases (cancer, cardiovascular disease, respiratory disease, type 2 diabetes) now experienced by both rich and poor countries throughout the world.

As the Bloomberg account explains,

Company officials join political leaders and health groups to come up with a plan to reverse the rising tide of non- communicable diseases….On the table are proposals to fight obesity, cut tobacco and alcohol use and expand access to lifesaving drugs in an effort to tackle unhealthy diets and lifestyles that drive three of every five deaths worldwide. At stake for the makers of snacks, drinks, cigarettes and drugs is a market with combined sales of more than $2 trillion worldwide last year.

Commenting on the collaboration of food companies in this effort:

“It’s kind of like letting Dracula advise on blood bank security,” said Jorge Alday, associate director of policy with World Lung Foundation, which lobbies for tobacco control.

The lobbying, to understate the matter, is intense.  On one side are food corporations with a heavy financial stake in selling products in developing countries.  Derek Yach, for example, a senior executive of PepsiCo, argues in the British Medical Journal that it’s too simplistic to recommend nutritional changes to reduce chronic disease risk.  [Of course it is, but surely cutting down on fast food, junk food, and sodas ought to be a good first step?]

On the other side are public health advocates concerned about conflicts of interest in the World Health Organization.  So is the United Nations’ special rapporteur for  the right to food, Olivier De Schutter.  Mr. De Schutter writes that the “chance to crack down on bad diets must not be missed.”

On the basis of several investigative visits to developing countries,  De Schutter calls for “the adoption of a host of initiatives, such as taxing unhealthy products and regulating harmful food marketing practices…Voluntary guidelines are not enough. World leaders must not bow to industry pressure.”

If we are serious about tackling the rise of cancer and heart disease, we need to make ambitious, binding commitments to tackle one of the root causes – the food that we eat.

The World Health Organization’s (WHO) 2004 Global Strategy on Diet, Physical Activity and Health must be translated into concrete action: it is unacceptable that when lives are at stake, we go no further than soft, promotional measures that ultimately rely on consumer choice, without addressing the supply side of the food chain.

It is crucial for world leaders to counter food industry efforts to sell unbalanced processed products and ready-to-serve meals too rich in trans fats and saturated fats, salt and sugars. Food advertising is proven to have a strong impact on children, and must be strictly regulated in order to avoid the development of bad eating habits early in life.

A comprehensive strategy on combating bad diets should also address the farm policies which make some types of food more available than others…Currently, agricultural policies encourage the production of grains, rich in carbohydrates but relatively poor in micronutrients, at the expense of the production of fruits and vegetables.

We need to question how subsidies are targeted and improve access to markets for the most nutritious foods.…The public health consequences are dramatic, and they affect disproportionately those with the lowest incomes.

In 2004, the U.N. caved in to pressures from food companies and weakened its guidelines and recommendations.  The health situation is worse now and affects people in developing as well as industrialized countries.  Let’s hope the General Assembly puts health above politics this time.

 

Sep 15 2011

Harvard plate v. USDA MyPlate: an improvement?

Scientists from the Harvard School of Public Health have come up with a new Healthy Eating Plate as an alternative to USDA’s MyPlate released last June.

 For an explanation, see the Harvard group’s press release.  Harvard intends this as an explicit challenge to the USDA’s version

Recall my deconstruction of the USDA plate when it first came out.

I’d love to hear what you think of the Harvard version.

Is it better? Likely to be more effective?

 

Weigh in, please.

Aug 8 2011

It’s time for some Q and A’s

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.