by Marion Nestle

Currently browsing posts about: Dietary-Guidelines

Jul 16 2020

Dietary Guidelines Advisory Committee releases report

The report of the 2020 Dietary Guidelines Advisory Committee is now available in online preprint.

It sets a record at 835 pages.

Its conclusions are highly consistent with those of previous Dietary Guidelines.

It recommends eating more of these foods:

Common characteristics of dietary patterns associated with positive health outcomes include higher intake of vegetables, fruits, legumes, whole grains, low- or nonfat dairy, lean meat and poultry, seafood, nuts, and unsaturated vegetable oils.

It recommends eating less of these foods:

The Committee found that negative (detrimental) health outcomes were associated with dietary patterns characterized by higher intake of red and processed meats, sugar-sweetened foods and beverages, and refined grains.

It retained the recommendation: Eat less red and processed meats

It retained the recommendation to eat less saturated fat (replace with polyunsaturated or monounsaturated)

Thus, the Committee recommends that dietary cholesterol and saturated fat intake be as low as possible within a healthy dietary pattern, and that saturated fat intake be limited to less than of 10 percent of total energy intake, as recommended by the 2015-2020 Dietary Guidelines for Americans. This recommendation applies to adults and children ages 2 years and older.

It tightened up restrictions on alcoholic beverages from 2 drinks a day for men to 1 drink:

The Committee concluded that no evidence exists to relax current Dietary Guidelines for Americans recommendations, and there is evidence to tighten them for men such that recommended limits for both men and women who drink would be 1 drink per day on days when alcohol is consumed.

It tightened up restrictions on added sugars, from 10% of calories to 6%:

After considering the scientific evidence for the potential health impacts of added sugars intake, along with findings from model-based estimations of energy available in the dietary pattern after meeting nutrient requirements, the Committee suggests that less than 6 percent of energy from added sugars is more consistent with a dietary pattern that is nutritionally adequate while avoiding excess energy intake from added sugars than is a pattern with less than 10 percent energy from added sugars.

What’s missing?

  • Salt: The report says remarkably little about sodium beyond that it is overconsumed and people should “reduce sodium intake.”  It’s possible that I missed it, but I could not find suggestions for quantitative limits.
  • Ultraprocessed: The word does not appear in the report except in the references.  A large body of evidence supports an association of ultraprocessed foods to poor health.  If the committee considered this evidence, it did not spell it out explicitly.
  • Sustainability: This was off the table from the beginning but this committee recommends that it be considered next time in the context of a food systems approach to the Dietary Guidelines (p.771).

Comment

This is an impressive, solid, conservative review of the existing science highly consistent with previous Dietary Guidelines but with mostly stronger recommendations.

This committee was up against:

  • A tight time frame
  • A first-time mandate to review literature on infancy, pregnancy, and lactation in addition to that for adults
  • A first-time process in which the agencies set the research agenda, not the committee
  • The Coronavirus pandemic

At the outset, I was concerned that the committee members might be heavily biased in favor of food industry interests.  If they were, such biases do not show up in the final report.  I think this committee deserves much praise for producing a report of this quality under these circumstances.

Want to weigh in on it? 

The agencies are taking public comments until August 13.  On August 11, there will be an online public meeting for even more comments.

What’s next?

This report is advisory, only.  USDA and HHS must boil this down to the actual 2020 Dietary Guidelines.  Whereas the committee process was transparent, the boiling down process is highly secretive, or was in 2015.  It will be interesting to see what the agencies do, especially given the heavy lobbying by proponents of meat, saturated fat, and low-carbohydrate diets.

Jun 17 2020

The Dietary Guidelines Advisory Committee reports in today

The Dietary Guidelines Advisory Committee (DGAC) meets today to talk about its draft report.  Register for it here.  

The agenda is here.

Reporters tell me that the DGAC report will not be released at this meeting; it is not ready.

Here’s what today’s announcement says:

The Committee will finalize their advisory report based on Committee discussion at the meeting. They will then submit their final report to the Secretaries of USDA and HHS. USDA and HHS will post the final report online, send out a public notification, and open a new public comment period for the Departments to accept comments on the Committee’s report. This action is expected on or around July 15, 2020.

This meeting is being held despite calls for delay.  Politico’s Helena Bottemillier Evich describes these calls under “Influential groups press for delay of Dietary Guidelines” (behind a paywall at the moment).

The groups are turning up the pressure ahead of the committee’s final public meeting on Wednesday, where the panel will discuss its draft conclusion statements. The committee is then expected to release in mid-July a sweeping scientific report to advise the Agriculture Department and Department of Health and Human Services on what the 2020 iteration of the guidelines should say.

Some of the Dietary Guidelines’ staunchest allies and fiercest critics — including professional groups and low-carb advocates — are urging a delay. They note that last year’s government shutdown and the continuing pandemic have made it more difficult for the committee to complete the necessary work before advising the government on the 2020 guidelines, which will last five years.

Corporate Accountability notes the undue influence of industry on the guidelines.  One of its recent reports documents ties of DGAC members to ILSI, an industry front group.

The guidelines are subject to criticism from just about everyone (me too).  I’m interested to see what this committee does.  Stay tuned.

Apr 3 2020

Coronavirus: Weekend advice about what and how to eat

The Mexican food advocacy group, Alianza por la Salud Alimentaria, has produced this guide for taking care of your food needs during this emergency.

And here’s a general survival guide.

Mar 4 2020

Coca-Cola wants the 2020 dietary guidelines to say more about beverages

I am indebted to Margarita Raycheva, who writes for the highly informative newsletter, IEG Policy Agribusiness, for her recent article, which certainly got my attention: “Coca-Cola asks DGAC to develop detailed dietary recommendations for beverages” (this is probably behind a paywall).

Her article is about comments filed by Coca-Cola to the DGAC, the 2020 Dietary Guidelines Advisory Committee.  She did not provide a link to those comments, so I had to search for them.  This involved finding the DGAC comments page, searching for Coca-Cola, locating the company’s letter, and opening the pdf attachment.

The 12-page document reads like a highly sophisticated advertisement for Coca-Cola’s astounding number of beverage options, many of them low in sugar or sugar-free.

Over the last few years, Coca-Cola has been transforming to become a total beverage company that meets Americans’ fast-changing preferences across a wide array of beverage categories. We support the World Health Organization’s recommendation that people should limit added sugar to no more than 10% of their total daily calorie consumption1 and are rethinking existing recipes, package sizes and offerings to ensure we are helping consumers manage their daily intake of added sugar and other nutrients from our portfolio.  Today, we offer more than 800 drinks in the U.S. alone, ranging from soft drinks to juices, teas, coffee, dairy, sports drinks, water and more – more than 250 of which are low- or zero-sugar options. More than 40% of our sparkling beverage brands in the U.S. are now available in package sizes that are smaller than 8.5 ounces. We are increasing marketing support for low-sugar, no-sugar and unsweetened products…; we are introducing less sweet versions of classic soft drinks…; and we are accelerating our expansion into new beverage categories through the acquisition of brands….We are taking these actions because we recognize the critical role that we – and the entire industry – can play in advancing nutritional goals by using our scale for good.

Why do this?

• About 15% of energy comes from beverages
• Beverages, such as sweetened soft drinks, coffee and tea contribute more than 40% of daily added sugar intake
• Beverages, mainly milk and 100% juice, contribute over 40% of vitamin C and D intake and more than 20% intake of carbohydrates, calcium, potassium and magnesium
• Fruit intake (0.9 cup/day) is half of recommended levels (2 cups/day); 100% fruit juice contributes up to 24% of fruit intake in children, but decreases after adolescence
• Coffee and tea contribute up to 12% of potassium intake in adults
• Waters contribute up to 10% of calcium intake in adults

In other words, drink more (of our) beverages!

Coca-Cola’s proposals for how beverages can enhance diets:

  • Hydration
  • Nutrition and health
  • Enjoyment
  • Performance

What should the DGAC do?

By creating a framework that includes guidance for all types of beverages, the DGA can help drive Americans towards healthier versions of drinks they are typically consuming. Recommending limited
consumption or small shifts towards healthier beverages is more effective than simply discouraging the consumption of entire beverage categories.

The company’s proposals for how the DGAC can help it sell more beverages include sample statements like these examples [with my translations]:

  • Water should be the primary beverage choice [recommend our bottled water]
  • Milk plays an important role in development and health, and contributes essential nutrients to healthy eating patterns, including protein, calcium, vitamin D and potassium [recommend our milk drinks]
  • When fortified, plant-based beverages may provide nutrients and support consumer choice, but generally should not be considered a replacement for dairy [please don’t recommend almond, soy, or oat milks–we don’t make any of those drinks]
  • Juice contributes to the public’s consumption of essential nutrients, phytonutrient and fruit/vegetable intake [recommend our juice drinks]
  • Coffee and tea are sources of health-promoting phytonutrients and are associated with reduced risk of rtain non-communicable diseases (NCDs) [recommend them; we sell those too]
  • Replace sugar-sweetened beverages >40 kcal that do not contribute significantly to nutrition needs with these beverages to reduce calorie and sugar consumption [if you must recommend avoing sugary beverages, at least recommend replacement with everything else we sell]
  • Sports drinks can be beneficial for individuals who engage in prolonged vigorous physical activity, or those sweating for prolonged hours due to warm to hot temperatures [OK, they have sugar, but recommend them anyway]

I can’t wait to see what the DGAC does with this impressively written document.

Not that it matters, really.  Recall: The DGAC submits the research report, but the agencies—USDA takes the lead this time—write the actual guidelines.

Sep 30 2019

Eat as much meat as you like? Really?

The press release from the Annals of Internal Medicine arrived last week under embargo, sent to me by several reporters: “New guidelines: No need to reduce red or processed meat consumption for good health.”

The press announcement was accompanied by 5 review papers, a sixth with this recommendation, and an editorial.  These are posted on the website of their publisher, the American College of Physicians, implying this organization’s endorsement of this guideline.

Collectively, these papers challenge dietary advice to eat less processed meat and red meat on the grounds of inadequate science.

These papers argue:

  • Eliminating processed and red meat from the diet may reduce disease risks but the effects are small and evidence for them is of low quality and low certainty.
  • Omnivores are unwilling to eat less meat.
  • If you continue to think eating meat is bad for you in the face of this evidence, you are a victim of the “the less you know, the more you hold to your beliefs” syndrome.
  • You can ignore dietary guidelines (regardless of source) and continuing eating meat as you always have.

This is a good example of what I call nutritional nihilism, an approach that insists that because observational studies are based on self-reported information and necessarily flawed, their conclusions are unscientific and should be discounted.  Therefore, because we can’t do more rigorous studies, we should not advise the public about diets best for health or the environment.

I have several concerns about all this:

  • Yes, the effects are small but that is true of nutrition studies in general.  The small effects show benefits from eating less meat.  The authors could easily have interpreted their work as suggesting that eating less meat might be useful.  This is an example of interpretation bias.
  • The authors took a strictly science-based approach to a problem strongly affected by social, economic, and political factors and values.
  • The studies look at previous studies that compared people who eat meat to those who eat less. The authors excluded studies of vegetarians compared to meat-eaters.
  • They look at meat outside its context of calories.
  • The authors did not look at the totality of the evidence; they excluded laboratory and animal studies that can be more closely controlled.
  • They excluded studies of environmental impact, which has a significant bearing on human dietary practices (meat production adds more greenhouse gases than vegetable production).
  • The conclusions fall into the category of “everything you thought you knew about nutrition is wrong.”  This rarely happens.  Science usually works incrementally, not in one enormous reversal like this.

Do the authors really believe that all those other committees and commissions urging less meat were wrong and continue to be wrong?   Their strictly science-based approach seems unrealistic.

The papers come across to me as a concerted attack on dietary guidelines (national and international), on nutrition science in general, and on nutritional epidemiology in particular.

The meat industry and its supporters will love them.

Attacks on the quality of nutrition research have been coming from many sources lately: the food industry, of course, but also statisticians (John Ioannidis at Stanford is making a career of this), and some scientists (usually with ties to food companies).  The criticisms themselves are not new.

What is new is the vehemence and level of effort to discredit observational studies, particularly those based on self-reports of dietary intake.  Yes, nutritional epidemiology has flaws, but the methods have been useful in many instances, as argued convincingly by two of its leading practitioners.

In looking at nutrition research, I think it is essential to evaluate the totality of information available: laboratory, animal, human epidemiology and clinical studies—and to do this in the context of what people actually eat and the number of calories they consume, as well as adding in a hefty dose of common sense.

Common sense is what’s missing in these studies.  Do the authors really believe that:

  • Meat eaters are healthier than vegetarians?
  • Eating more meat is better for health?
  • Meat eaters are less obese and have less heart disease and cancer than those who eat less?

If not, the conclusions make no sense.

Most of the authors report no financial ties to the food industry.  I would love to know the back story about why they chose to do these studies and to interpret them in this way.

Reactions (I will be adding to this list as they come in)

Feb 26 2019

At last: the 2020 Dietary Guidelines Advisory Committee

Very late in the process, the USDA and HHS have finally announced the membership of the Dietary Guidelines Advisory Committee for 2020:

Today the Secretaries of USDA and HHS announced 20 nationally recognized experts who have been selected to serve on the 2020 Dietary Guidelines Advisory Committee.

The independent Advisory Committee will review the scientific evidence on topics from the Departments and provide a report to the Secretaries that, along with public and agency comments, will help inform USDA and HHS’s development of the 2020-2025 Dietary Guidelines for Americans.

I know several of the members.  I served with Barbara Schneeman on the 1995 DGAC, for example.

Some members have financial ties to food companies with deep interests in the what the guidelines say.  This is despite the agencies’ statements that

The vetting process also included a background check by the USDA Office of the Secretary to determine if any of the candidates have a financial, ethical, legal, and/or criminal conflict of interest that would prohibit them from serving on the Committee…Each Committee member submitted a financial disclosure report prior to appointment and will continue to do so annually thereafter. Each report was reviewed by USDA ethics officials for financial conflicts of interest and compliance with Federal ethics rules.

Politico’s Helena Bottemiller Evich asked groups to say who they nominated to the committee.  What she found is here, but behind a paywall.  I’ve added the information from these lists in red.  She is still trying to find out who nominated the others.

  • Jamy Ard, MD – Wake Forest University
  • Regan Bailey, PhD, MPH, RD – Purdue University, Department of Nutrition Science Academy of Nutrition and Dietetics
  • Lydia Bazzano, MD, PhD – Tulane University  Atkins Nutritional
  • Carol Boushey, PhD, MPH, RD – University of Hawaii  National Cattlemen’s Beef Association
  • Teresa Davis, PhD – Baylor College of Medicine
  • Kathryn Dewey, PhD – University of California, Davis
  • Sharon Donovan, PhD, RD – University of Illinois
  • Steven Heymsfield, MD – Louisiana State University American Beverage Association
  • Ronald Kleinman, MD – Harvard University
  • Heather Leidy, PhD – University of Texas National Cattlemen’s Beef Association
  • Richard Mattes, PhD, MPH, RD – Purdue University Academy of Nutrition and Dietetics
  • Elizabeth Mayer-Davis, PhD, RD – University of North Carolina
  • Timothy Naimi, MD – Boston University
  • Rachel Novotny, PhD, RDN, LD – University of Hawaii
  • Joan Sabaté, DrPH, MD – Loma Linda University
  • Barbara Schneeman, PhD – University of California, Davis  American Beverage Association
  • Linda Snetselaar, PhD, RD – University of Iowa Academy of Nutrition and Dietetics
  • Jamie Stang, PhD – University of Minnesota, School of Public Health, Division of Epidemiology & Community Health Academy of Nutrition and Dietetics
  • Elsie Taveras, MD, MPH – Massachusetts General Hospital, Harvard Medical School, and Harvard Chan School of Public Health
  • Linda Van Horn, PhD, RDN, LD – Northwestern University

As for transparency:

Helena Bottemiller Evich (@hbottemiller) tweeted at 11:36 AM on Fri, Feb 22, 2019:
Everyone says they want a “more transparent” Dietary Guidelines process, but the minute I ask for who X group nominated to be on DGAC food/ag/health groups are like https://t.co/6J8GJnGpD7
(https://twitter.com/hbottemiller/status/1099030227009835008?s=03)

Overall, this looks to me like any other DGAC except that there are twice as many members as in the past.

Their job is to review the research and write a report.  The agencies write the guidelines.

I will be following all this with great interest, as always.

 

Jan 25 2019

Weekend reading: The Lancet / EAT Forum report on healthy and sustainable diets

I’ve saved this for Weekend Reading because it will take a weekend to get through it.  The report is a blockbuster: 37 authors, 47 pages, 357 references.

The Lancet commissioned this report from the EAT Forum, which brought together international experts on diet and health (most of whom I do not know) to define unifying dietary principles that best promote will promote the health of people and the planet.

Fortunately, the diet that is best for health is the same diet as is best for the planet.  The report defines it on page 5.

To summarize:

This report has many strengths:

  • It is researched in depth and is now the reference source for information about needed dietary changes.
  • It firmly links dietary health to environmental sustainability.
  • Its findings are consistent with many previous reports on diet and health, including that of the 2015 Dietary Guidelines Advisory Committee DGAC).
  • Its messages are unambiguous.
  • The summary report is a big help
  • The timing  is excellent; the 2020 Dietary Guidelines advisory committee, if it ever gets appointed, will have to pay close attention to the science reviewed in this report.
  • It focuses on food, not nutrients (these meals meet the standards of recommended diets).

Does this report settle the questions?  Hardly.  Remember the fuss over sustainability (the “S-word?”) in the 2015 report of the DGAC?

There is lots to read and think about here.  Enjoy!

Nov 20 2018

Healthy diets: Variety?

I was surprised to read a recent paper in the American Heart Association journal arguing that dietary diversity may not be good for health:

“Eat a variety of foods,” or dietary diversity, is a widely
accepted recommendation to promote a healthy, nutritionally adequate
diet and to reduce the risk of major chronic diseases. However, recent
evidence from observational studies suggests that greater dietary diversity is associated with suboptimal eating patterns, that is, higher intakes of processed foods, refined grains, and sugar-sweetened beverages and lower intakes of minimally processed foods, such as fish, fruits, and vegetables, and may be associated with weight gain and obesity in adult populations.

Obviously, eating a variety of junk food is unlikely to improve health.  But the variety recommendation has never been intended to include junk food.

Here’s a summary of the variety recommendations of the Dietary Guidelines from 1980 to 2015:

These have increasingly specified healthy foods.

Eat your veggies!  Enjoy!