by Marion Nestle

Currently browsing posts about: Uncategorized

Mar 24 2021

My latest publication: a book review

I’ve just had a book review published in the American Journal of Public Health: “Public health nutrition deserves more attention.”

It’s for a textbook on public health nutrition but doing it gave me the opportunity to say some things I want public health professionals to know.  I started the review like this:

Public Health Nutrition deserves more attention

Food and nutrition deserve much more attention from public health professionals.  On the grounds of prevalence alone, diet-related conditions affect enormous numbers of people.  Everybody eats.  Everybody is at risk of eating too little for health or survival, or too much to the point of weight gain and increased prevalence of non-communicable diseases (NCDs).  By the latest count, nearly 700 million people in the world do not get enough to eat on a daily basis, a number that has increased by tens of millions over the past five years and will surely increase by many millions more as a result of the Coronavirus pandemic.[i]   At the same time, about two billion adults are overweight or obese, and few countries are prepared to deal with the resulting onslaught of type 2 diabetes and heart disease.[ii]  Beyond that, food production, distribution, consumption, and disposal—collectively food systems—are responsible for a quarter or more of greenhouse gas emissions; climate change affects the health of everyone on the planet.[iii]

The same social, behavioral, economic, and structural determinants that affect health also affect nutritional health, and it is no accident that food choices are flash points for arguments about culture, identity, social class, inequity, and power, as well as about the role of government, private enterprise, and civil society in food systems.   From a public health standpoint, everyone–regardless of income, class, race, gender, or age—should have the power to choose diets that meet nutritional needs, promote health and longevity, protect the environment, and are affordable, culturally appropriate, and delicious.

Nutrition in 2021

For people in high-income countries, dietary prescriptions for health and sustainability advise eating less meat but more foods from plant sources.[iv]  Optimal diets should minimize consumption of ultra-processed foods, those that are industrially produced, bear little resemblance to the basic foods from which they were derived, cannot be prepared in home kitchens, and are now compellingly associated with NCD risk and mortality.[v]  We now know that ultra-processed foods encourage people to unwittingly take in more calories and gain weight.[vi]

Agenda for 2021

Today, a book for researchers and practitioners of public health nutrition needs to emphasize coordinated—triple-duty—recommendations and interventions to deal with hunger and food insecurity, obesity and its consequences, and the effects of food production and dietary choices on the environment.  Such approaches, as described by a Lancet Commission early in 2019,4 should encourage populations of high-income countries to eat less meat but more vegetables, those in lower- and middle-income countries (LMICs) to consume a greater variety of foods, and everyone, everywhere to reduce intake of ultra-processed foods.  As that Commission argued, public health nutritionists must recognize that attempts to improve diets, nutritional status, nutritional inequities, and food systems face daunting barriers from governments captured by corporations, civil society too weak to demand more democratic institutions, and food companies granted far too much power to prioritize profits at the expense of public health.  Nutritionists need knowledge and the tools to resist food company marketing and lobbying, to advocate for regulatory controls of those practices, and to promote civil society actions to demand healthier and more sustainable food systems.[vii]

I then go on to talk about the book itself, which alas, did not have much to say about this agenda.

References to the first part of this review

[i] The World Bank.  Brief: Food Security and COVID-19. December 14, 2020. https://www.worldbank.org/en/topic/agriculture/brief/food-security-and-covid-19#:~:text=In%20November%202020%2C%20the%20U.N.,insecure%20people%20in%20the%20world. Accessed January 2, 2021.

[ii] WHO.  Obesity and overweight: Key facts.  Geneva: WHO.  April 1, 2020. https://www.who.int/news-room/fact-sheets/detail/obesity-and-overweight. Accessed January 2, 2021.

[iii] International Panel of Experts on Sustainable Food Systems. COVID-19 and the crisis in food systems: symptoms, causes, and potential solutions. IPES-Food, April 2020. www.ipesfood.org/pages/covid19. Accessed January 2, 2021.

[iv] Swinburn BA, Kraak V, Allender S, et al. The global syndemic of obesity, undernutrition, and climate change: The Lancet Commission report. Lancet. 2019;393:791–846.

[v]  Monteiro CA, Cannon G, Levy RB, et al.  Ultra-processed foods: what they are and how to identify them. Public Health Nutr. 2019;22(5):936–941.

[vi] Hall KD, Ayuketah A, Brychta R, et al. Ultra-processed diets cause excess calorie intake and weight gain: an inpatient randomized controlled trial of ad libitum food intake. Cell Metab. 2019;30, 67–77.

[vii]  Jayaraman S, De Master K, eds.  Bite Back: People Taking On Corporate Food and Winning.  Oakland, CA: University of California Press; 2020.

 

 

Mar 23 2021

Vitamin C and the common cold. Again? Really?

I cannot believe that we are still talking about whether vitamin C prevents colds.  No such luck.

What triggered this is a recent and quite detailed critique of a 2018 meta-analysis of studies of this question: “Extra Dose of Vitamin C Based on a Daily Supplementation Shortens the Common Cold: A Meta-Analysis of 9 Randomized Controlled Trials.”

Its conclusion:  “The combination of supplemental and therapeutic doses of vitamin C is capable of relieving chest pain, fever, and chills, as well as shortening the time of confinement indoors and mean duration.”

You can read the detailed critique of this study for yourself, but I thought this was settled years ago by one of my all-time favorite nutrition studies: Karlowski TR, Chalmers TC, Frenkel LD, Kapikian AZ, Lewis TL, Lynch JM. Ascorbic acid for the common cold. A prophylactic and therapeutic trialJAMA 1975; 231: 1038–1042.

This fabulous study was done at NIH using NIH employees.  As the abstract puts it,

Three hundred eleven employees of the National Institutes of Health volunteered to take 1 gm of ascorbic acid or lactose placebo in capsules three times a day for nine months. At the onset of a cold, the volunteers were given an additional 3 gm daily of either a placebo or ascorbic acid.

The initial analysis of the data showed a highly significant effect of vitamin C in preventing colds or reducing symptoms.  But the trial had one major flaw: it had an usually big dropout rate.

One hundred ninety volunteers completed the study. Dropouts were defined as those who missed at least one month of drug ingestion. They represented 44% of the placebo group and 34% of those taking ascorbic acid.

These were good investigators.  They asked the dropouts why they had dropped out.  The reason: the study subjects knew (well, they thought they knew) whether they were taking vitamin C or the placebo.

The investigators reanalyzed the data according to what the study subjects thought they were taking.  Those who thought they were taking vitamin C had fewer colds and reduced symptoms—regardless of whether they were taking vitamin C or the placebo.  And those who thought they were taking the placebo had more colds and worse symptoms regardless of whether they really were taking the placebo or were actually taking vitamin C.

The authors’ cautious conclusion:

Analysis of these data showed that ascorbic acid had at best only a minor influence on the duration and severity of colds, and that the effects demonstrated might be explained equally well by a break in the double blind.

My conclusion: Vitamin C is one terrific placebo.

Nothing wrong with that, but that’s why I can’t believe investigators are still arguing about it.

Mar 22 2021

Annals of marketing: walnuts as plant-based meats

The California Walnut Commission, ever on the job, has a new white paper out on using walnuts as ingredients in plant-based meat substitutes.

The paper rightly points out that the most popular plant-based meats are full of artificial ingredients (they don’t use the word “ultra-processed).

The public wants “clean.”

The sweet spot for manufacturers is in creating great-tasting plant-based products while maintaining clean labels. Walnuts are a popular tree nut and the ideal ingredient for many uses in plant-based meat alternatives. Want to mimic meat in taco crumbles or provide a savory taste and exceptional texture to a plant-based burger? Use walnuts.

Apparently, such products are on the market already (the white paper gives examples).

My question, as always, how do they taste?

I will look for them and find out.  With luck, they will taste like walnuts.

Expect trade associations for every kind of nut to get on this bandwagon, if they haven’t already done so.

 

 

Mar 19 2021

Weekend reading: Michael Moss’s Hooked

Michael Moss.  Hooked: Food, Free Will,and How the Food Giants Exploit Our Addictions.  Random House, 2021.

This follows Michael Moss’s Salt Sugar Fat which was about how food companies used these ingredients to hook us on junk food.  The new book focuses on the “addictive” qualities of junk foods—what we are now calling “ultra-processed.”  I put addictive in quotes because his definition is looser than others I’ve seen: habits that are hard to quit.

By this definition, his book provides convincing evidence for what food companies do to make their products irresistible—remember Frito Lay’s “You can’t eat just one?”

The book starts by going into the physiology of addiction:

When we taste sugar, the taste buds on our tongue send the signal.  By contrast, the signal for fat gets transmitted by the trigeminal nerve that extends from the roof of the mouth to the brain.  Food that has both sugar and fat will activate these two different paths, sending to separate alerts, and thus doubling the arousal of a brain that appears to place a high value on information for information’s sake [62].

No wonder we like ice cream so much.

In speaking about how the food environment sets us up for overeating, he says:

…we simply haven’t had anywhere near the time we would need, vis-à-vis evolution, to catch up with the dramatic changes in food and our eating habits of the past forty years.  As a result, we are fundamentally mismatched to the food of today.  Small [Dana Small, an expert Moss interviewed] puts it this way: “It’s not so much that food is addictive, but rather that we by nature are drawn to eating, and the companies have changed the food [p. 99].

Moss is a terrific writer and tells a compelling story.  Even if you don’t have a problem resisting fast food, sodas, or chocolate, this book has a lot to say about why so many people have put on pounds during the Covid-19 pandemic.

 

Mar 18 2021

What’s happening with Brexit?

The UK’s departure from the European Union is now a done deal, but its impact is only just now becaming clear.  Here are some observations of what’s happening.

Mar 17 2021

Overweight is a major risk factor for Covid-19 hospitalization and death

I was struck by headlines last week stating that a CDC study found that 78% of people hospitalized with Covid-19 were overweight or obese.

78%?  That is an enormous percentage.

I looked up the study: Body “Mass Index and Risk for COVID-19–Related Hospitalization, Intensive Care Unit Admission, Invasive Mechanical Ventilation, and Death — United States, March–December 2020.”

Summary

What is already known about this topic?

Obesity increases the risk for severe COVID-19–associated illness.

What is added by this report?

Among 148,494 U.S. adults with COVID-19, a nonlinear relationship was found between body mass index (BMI) and COVID-19 severity, with lowest risks at BMIs near the threshold between healthy weight and overweight in most instances, then increasing with higher BMI. Overweight and obesity were risk factors for invasive mechanical ventilation. Obesity was a risk factor for hospitalization and death, particularly among adults aged <65 years.

What are the implications for public health practice?

These findings highlight clinical and public health implications of higher BMIs, including the need for intensive management of COVID-19–associated illness, continued vaccine prioritization and masking, and policies to support healthy behaviors.

The data supporting the headline are found in Table 1 in the paper.  This shows that overweight and obesity do indeed account for 78% of hospitalizations, but also close to that percentage for ICU visits and mechanical ventilation, but “only” 73% of deaths.

Overweight and obesity were especially risky for people under age 65, although they caused plenty of problems for people over age 65 too.

Why do they make Covid-19 worse?  The best guesses have to do with inflammation and mechanical pressure on lungs.

I found these figures shockingly high.

Shouldn’t we be doing all we can to reduce the risks for overweight and obesity?  Yes we should.

And what are those risks?

  • Poverty
  • Racial discrimination
  • Inadequate schools
  • Unemployment
  • Lack of adequate health care
  • Air pollution
  • And, of course, poor diets

If Covid-19 has taught us anything, it is that to prevent its bad effects, we need vaccinations and masking for sure, but we also need to change society.

 

Mar 16 2021

What does the $1.9 trillion stimulus bill do for the food system?

The American Rescue Plan Act of 2021, otherwise known as the $1.9 trillion stimulus bill has lots of bits and pieces to strengthen elements of the food system.

This bill:

  • Extends the 15% increase in SNAP benefits through September 30, 2021
  • Makes more SNAP benefits available to Puerto Rico, Samoa, Marianas
  • Increases support for WIC, especially for fruit and vegetable purchases
  • Continues Pandemic-EBT (free meals for school children excluded from schools)
  • Provides funds for debt relief and outreach for socially disadvantaged farmers
  • Establishes a new grant program for restaurants and bars to meet payroll and other expenses
  • Expands income support for families with children through tax credits for child care and earned income

In addition, the Biden Administrration has done some other things to reduce food insecurity

What’s still needed:

  • A comprehensive plan for creating a food system that promotes health and sustainability
  • Universal school meals
  • Universal Basic Income

Some of these new measures are steps in that direction.  They just need to be continued.  Advocate!

Mar 15 2021

Annals of food industry marketing: potatoes

I like potatoes and they have plenty of nutritional value along with their calories, but their calories mainly come from starch—a rapidly digested carbohydrate.

The Harvard Food Pyramid puts potatoes in the “Eat Sparingly” category, right at the top with red meat, butter, and sugary beverages.

Potato industry marketers to the rescue!  Take a look at the website of Potatoes USA, which has as its mission developing marketing campaigns for the industry.

Industry participation is key to making any campaign a success. Here you’ll find marketing tools that will help you promote the positive potato nutrition message.  Find the tools that match your organization, whether you’re looking for resources for retailersmanufacturersconsumersfoodservice operators, or information on potato nutrition.

Here you can find a toolkit on how to market potatoes:

For years we’ve talked about why you can eat potatoes. Now we’re talking about why you should eat potatoes. Getting the whole industry involved is key to getting this message heard. Find the tools you need to support the process with events in your area.

I was interested in what they have to say about nutrition, of course: “Potatoes are more energy-packed than any other popular vegetable and provide the carbohydrates, potassium and energy you need to perform your best.”

The nutrition campaign focuses on energy for performance.  It provides a Nutrition Facts label that reassures you that one 5.3-ounce potato has only 110 calories.

It doesn’t say much—anything, really—about how Americans mostly eat potatoes, which happens to be as fries or chips.

It does provide tons of information about marketing methods, the research sponsored by the potato industry, and even issues regarding international trade—a goldmine if you are interested in this sort of thing.

If you just want to eat them, watch out for the added fats.  The bigger the potato—and the more butter and sour cream—the higher the calories.