by Marion Nestle

Currently browsing posts about: Dietary-Guidelines

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.

Jun 26 2011

Eat French fries, gain weight?

A reader, Thibault H writes:

So Harvard University came out with a study that news reporters are saying tells us that those who tend to eat more potatoes gain x amount of weight over 10 years…What do you make of this?…could it be possible that potatoes themselves are not the culprit and rather those who tend to eat more potatoes have a fattier diet or perhaps more sedentary lifestyle.

It could indeed.  The study, which came out in the New England Journal of Medicine last week, looked at the weight gained by more than 100,000 people who had filled out diet questionnaires in 1986 or later.  It correlates what people said they ate with weight gained over periods of 4 years:

The results show that people who said they habitually ate potato chips, potatoes, or fries—as well as the the other foods in the top part of the diagram—were more likely to gain weight.

People who reported frequent eating of the foods in the lower part of the diagram were likely to have lost weight.

What fun!  The study assigns pounds of weight gained or lost to specific foods.

The study also did a more detailed analysis.  This showed that French fries were linked to the greatest weight gain: 3.35 pounds over a 4-year period.  If you habitually eat French fries, you may have a hard time controlling your weight.

No surprise.  I recently ordered a side of fries in an excellent restaurant and was floored by the size of the order Eat a small handful: no problem.  But this order surely hit 800 calories.  Fortunately, there were four of us to share it.

Here’s how I explained the study to Katherine Hobsen of the Wall Street Journal (June 23):

Marion Nestle, New York University professor of nutrition and public health, expressed surprise that potato products were linked with more weight gain than desserts like cake, cookies and doughnuts, which contribute the most calories to the American diet, other research shows. She says she suspects people who eat potato chips and fries also tend to eat too much in general, making these foods markers for a diet leading to weight gain.

The new Dietery Guidelines “policy document” has a particularly entertaining chart of the leading sources of calories in U.S. diets.  Here are the top six, in order:

  • “Grain-based” desserts (translation: cakes, pies, cookies, cupcakes, etc)
  • Breads
  • Chicken and chicken mixed dishes (translation: fingers)
  • Sodas, energy, and sports drinks
  • Pizza
  • Alcoholic beverages

Potato chips are #11 and fries are #17.

This new study provides evidence supporting what everyone surely ought to know by now: eat your veggies!

P.S.  Here’s Andy Bellatti’s take on this study.  His point: it’s not the carbs, it’s calories.

 

 

 

Apr 10 2011

Dietary Guidelines, 1861 (they haven’t changed much….)

I’m at a meeting in Washington DC of the American Society of Nutrition. At the exhibits, David Schnackenberg, who runs a website on the history of military nutrition, gave me these dietary guidelines from 1861. They are from a monograph by Dr. John Ordonaux, “Hints on the Preservation of Health in the Armies: for the Use of Volunteer Officers and Soldiers.”

  • Soldiers should be fed a mixed diet of animal and vegetable substances.
  • A variety of foods are needed to avoid monotony and increase assimilation.
  • A healthy diet must conform to the physiological requirements of the season with less animal fats in the summer dietary, and more starch, vegetables, and fruits.
  • Fresh fruits are always preferable to dry or preserved ones.
  • Farinaceous vegetables are more nourishing than roots or grasses.
  • The best soldiers in the world are fed on dark colored bread.
  • French army dietaries provide nutritious soups made with meat or vegetables.
  • The woody fibre of the vegetable provides bulk as well as nourishment.
  • Each company should have at least one educated cook.
  • Beans, unless thoroughly cooked, are only fit for horses. When half-cooked, they will provoke indigestion and diarrhea.
  • Ardent spirits are not necessary for health and the soldier is better off without them.
  • Soldiers must be well fed to bear the fatigues of marching, to encounter unaffected the changes of climate, and to develop a high muscular tone.

As I keep saying, basic nutrition advice has, in fact, not changed much over the years.  The big change in the last 150 years is the invention of junk foods. Dr. Ordonaux did not have snacks and sodas to contend with, nor today’s extensive obesity among army recruits.