Search results: dietary guidelines

Eating fish presents difficult dilemmas (I evaluate them in five chapters of What to Eat).

This one is about asking pregnant women to weigh the benefits of fish-eating against the hazards of their toxic chemical contaminants to the developing fetus.

The Dietary Guidelines tell pregnant women to eat 2-to-3 servings of low-mercury fish per week (actually, it’s methylmercury that is of concern, but the FDA calls it mercury and I will too).

But to do that, pregnant women have to:

• Know which fish are low in mercury
• Recognize these fish at the supermarket, even if they are mislabeled (which they sometimes are).

Only a few fish, all large predators, are high in mercury.  The FDA advisory says these are:

• Shark
• Swordfish
• King Mackerel
• Tilefish

What?  This list leaves off the fifth large predator: Albacore (white) tuna.  This tuna has about half the mercury as the other four, but still much more than other kinds of fish.

The figure below comes from the Institute of Medicine’s fish report.  It shows that fish highest in omega-3 fatty acids, the ones that are supposed to promote neurological development in the fetus and cognitive development in infants, are also highest in mercury.

White tuna is the line toward the bottom.  The ones in the blue boxes are all much lower in omega-3s and in mercury except for farmed Atlantic salmon (high in omega-3s, very low in mercury).

What’s going on here?

• Tuna producers know you can’t tell the difference between white and other kinds of tuna and don’t want you to stop eating tuna during pregnancy.
• The data on the importance of eating fish to children’s cognitive development are questionable (in my opinion).  The studies are short term and it’s difficult to know whether the small gains in early cognitive development that have been reported make any difference a few months later.
• The FDA must be under intense pressure to promote fish consumption.

I think it is absurd to require pregnant women to know which fish to avoid.  In supermarkets, fish can look pretty much alike and you cannot count on fish sellers to know the differences.

Other dilemmas:

• Even smaller fish have PCBs, another toxin best avoided by pregnant women, if not everyone.
• The world’s seafood supply is falling rapidly as a result of overfishing.
• Half of the mercury in seafood derives from emissions from coal-burning power plants.  The best way to reduce mercury in fish is to clean up the emissions from those plants, but plant owners want to avoid the expense.

That’s fish politics, for you.

The FDA documents:

• Press Release: FDA and EPA Issue Draft Updated Advice for Fish Consumption
• FDA and EPA Draft Updated Advice for Fish Consumption (open for public comment)
• Federal Register Notice – Environmental Protection Agency and Food and Drug Administration Advice About Eating Fish: Availability of Draft Update
• Consumer Update: New Advice: Some Women and Children Should Eat More Fish
• Dietary Guidelines for American’s 2010
• Quantitative Assessment of the Net Effects on Fetal Neurodevelopment from Eating Commercial Fish

Mal Nesheim and I have an editorial in a recent issue of the American Journal of Clinical Nutrition: “Advice for fish consumption: challenging dilemmas.”

We commented on a research article evaluating blood mercury levels in adults eating seafood.

In it, we point out that

the 2010 Dietary Guidelines for Americans advise Americans to consume 8 ounces (227 g) of seafood per week to reach an average intake of 250 mg/d of the omega-3 fatty acids EPA and DHA.

This recommendation represents a substantial increase over current consumption amounts of ∼3.5 oz/wk. It is based on “moderate, consistent evidence” that the health benefits of increased seafood consumption outweigh the risks associated with methylmercury, a toxic contaminant of large predatory food fish (tilefish, shark, swordfish, king mackerel) and, to a lesser extent, albacore (white) tuna.

To avoid this toxin, the guidelines advise eating seafood typically found to be low in methylmercury, such as salmon, anchovies, sardines, and trout.

Such advice, however, leads to at least 3 dilemmas. Eating more fish might raise methylmercury intake above safe amounts. Pressures to consume more fish might place impossible demands on an already threatened seafood supply. And the obvious solution—fish farming—raises concerns about what farmed fish are fed and how farmed fish affects the environment.

We urge the 2015 Dietary Guidelines committee to take all this into consideration when making recommendations about fish consumption: “We hope that its advice for seafood consumption will help a confused public resolve some of these dilemmas and make wise seafood choices.”

Wise seafood choices may be an oxymoron, alas.

Nicholas Kristof of the New York Times recently devoted a column to an analysis of who really gets welfare in the United States.  He listed policies that favor not only the wealthy, but the fabulously wealthy:

• Subsidies for private airplanes via tax write-offs and deductions
• Tax deductions for private yachts
• Tax deductions for hedge funds and private equity
• Bank rescues
• Incentives to operate locally

His column reminded me of one written in 2005 by Sean Faircloth, then a Maine State representative, “Six ways government promotes obesity and what to do about it.”

No government, Faircloth said, could have devised more effective policies for reducing physical activity and promoting junk food.  Taxpayers, he pointed out:

• Subsidize oil companies and cars to the detriment of trails and sidewalks.
• Make it impractical to get basic information in foods and restaurants (menu labeling regulations: where are you?).
• Give large corporations free reign to market to children.
• Allow soda and snack-food companies to market products in schools (USDA is trying to change this).
• Direct billions in subsidies toward processed foods while neglecting fresh produce.
• Promote high-calorie foods in programs for poor people.

I thought this was an interesting way of thinking about obesity policy and over the years have added these:

• Allowing marketing costs to be deducted from taxes as business expenses
• Bans on lawsuits against food companies
• Ambiguous and obfuscating dietary guidelines (e.g. SoFAS in the 2010 edition)

No doubt there are others.

Can you think of any others?  Thanks.

What is a poor eater to do?

The latest meta-analysis of the effects of saturated fat on heart disease finds—none.

This study, reported in the Annals of Internal Medicine (doi: 10.7326/M13-1788), examined the results of

• 32 observational studies involving 530 525 participants
• 17 observational studies involving 25 721 participants
• 27 randomized controlled trials involving 103 052 participants

The result?

Current evidence does not clearly support cardiovascular guidelines that encourage high consumption of polyunsaturated fatty acids and low consumption of total saturated fats. 

This meta-analysis follows an editorial in a Mayo Clinic publication (http://dx.doi.org/10.1016/j.mayocp.2013.11.006) by authors who argue that saturated fat is not the problem.  Carbohydrates (e.g., sugars) are the problem.  The authors argue:

• Effects of saturated fat on blood cholesterol are weak and transient.
• Meta-analyses have found a lack of an association between heart disease mortality and saturated fat intake.
• Stroke studies find that patients with stroke had eaten less saturated fat.
• Long-term studies find that people with the highest dairy consumption have the lowest mortality risk, and also low diabetes and heart disease.
• Dietary trials find trivial or no benefit at all from decreasing saturated fat and/or increasing intake of polyunsaturated fat.

On this basis, they say that advice to reduce intake of saturated fat is irrational.

The New York Times asked several experts for comment on the meta-analysis, among them Dr. Frank Hu of Harvard:

The single macronutrient approach is outdated…I think future dietary guidelines will put more and more emphasis on real food rather than giving an absolute upper limit or cutoff point for certain macronutrients…people should try to eat foods that are typical of the Mediterranean diet, like nuts, fish, avocado, high-fiber grains and olive oil.

Dr. Hu was referring to a large clinical trial (not included in the meta-analysis), which concluded that a diet with more nuts and extra virgin olive oil reduced heart attacks and strokes when compared with a lower fat diet with more starches.

The Times story contained a reminder that the American Heart Association issued dietary guidelines last year to “restrict saturated fat to as little as 5 percent of their daily calories, or roughly two tablespoons of butter or two ounces of Cheddar cheese for the typical person eating about 2,000 calories a day.”

How to make sense of this?

I vote with Frank Hu that dietary advice should focus on food, not nutrients.

Focusing on one or another nutrient—fat, saturated fat, cholesterol, or sugar—takes foods out of their caloric as well as dietary context.

My guess: If you balance food intake with physical activity and are not overeating, the specific proportion of fat, carbohydrate, and protein won’t matter nearly as much.

While the arguments about fat v. sugar go on and on:  Eat your veggies, vary the foods you eat, don’t gorge, and enjoy what you eat.

On Friday, President Obama signed the Agriculture Act of 2014, a.k.a. the farm bill.

 The green object on the left is a John Deere tractor.  Why is it there?

The John Deere company:

• Sells crop insurance.
• Is one of the 18 insurance companies that benefit handsomely from the newly revised law.
• Gives widely to members of Congress (both parties).

The bill has 12 titles or sections:

1. Commodities
2. Conservation
3. Trade
4. Nutrition
5. Credit
6. Rural Development
7. Research, Extension, and Related Matters
8. Forestry
9. Energy
10. Horticulture
11. Crop Insurance
12. Miscellaneous

I took a quick look at what’s new in Title 4: Nutrition—the part that deals with SNAP.  Here are a few of its details [with my comments]:

Sec. 4001. Preventing payment of cash to recipients of supplemental nutrition assistance benefits for the return of empty bottles and cans used to contain food purchased with benefits provided under the program.  [This closes a loophole but hardly seems worth the trouble—how much cash is involved here?  And won’t it be impossible to enforce?]

Sec. 4018.  No funds authorized to be appropriated under this Act shall be used by the Secretary for recruitment activities designed to persuade an individual to apply for supplemental nutrition assistance program benefits. [This one is especially troubling, as it eliminates USDA outreach activities to people who might be eligible for benefits but don’t know about them.]

Sec. 4028. Nutrition education is to include physical activity in addition to healthy food choices.  [Translation: Focus obesity-prevention efforts on activity, not on making fewer purchases of junk foods and sodas.]

Sec. 4202.  The Secretary [of USDA] shall conduct a pilot project…[to] facilitate the procurement of unprocessed fruits and vegetables in not more than 8 States. [It’s only a pilot program but it’s to promote local farm-to-school programs! Score this one as a small win.] 

Sec. 4204.  Not later than the 2020 report [on the Dietary Guidelines for Americans] and in each report thereafter, the Secretaries [of USDA and HHS] shall include national nutritional and dietary information and guidelines for pregnant women and children from birth until the age of 2.  [I’m baffled by this one.  Current Guidelines apply to everyone over the age of 2 and already contain advice for pregnant women.  I doubt this is meant to make sure that the Guidelines advise parents to avoid giving sodas to kids under the age of 2.]

Sec. 4208. Food Insecurity Nutrition Incentive.  This provides for competitive matching grants to increase the purchase of fruits and vegetables by SNAP participants.  [As discussed by Michele Simon and Daniel Bowman Simon, the bill does not necessarily favor local foods or purchases at farmers’ markets, and the size of the incentive is unclear.]

Sec. 4209.  Food and agriculture service learning program…to increase capacity for food, garden, and nutrition education within host organizations or entities and school cafeterias and in the classroom.  The USDA is to award competitive grants to entities that have a proven track record; work in underserved rural and urban communities; teach and engage children in experiential learning about agriculture, gardening, nutrition, cooking, and where food comes from; and facilitate a connection between elementary schools and secondary schools and agricultural producers in the local and regional area. [This must mean Food Corps.  The bill authorizes $25 million until spent, but the funding is not mandatory.  Will it be funded?  Fingers crossed.]

Sec. 4213.  Pulse crop products.  The [USDA] Secretary shall purchase eligible pulse crops and pulse crop products for use in the school lunch program…[and] the school breakfast program. [Bean growers—soybean growers?—must be doing some effective lobbying.]

Sec. 4214. The Secretary shall carry out a pilot project in schools participating in the Fresh Fruit and Vegetable Program…in not less than 5 States, to evaluate the impact of allowing schools to offer canned, frozen, or dried fruits and vegetables.  [It looks like the frozen food industry is also doing some effective lobbying.  Frozen vegetables are fine, but not if they mean giving up fresh ones.]

—Thanks to Daniel Bowman Simon for pointing out some of these issues and for providing links to relevant sources.

I’ve only just come across this USDA chart, which first appeared in an article in Amber Waves.

USDA’s Economic Research Service (ERS) researchers looked at 1998-2006 grocery store food expenditures and compared what consumers buy to dietary guidelines for healthy eating.  

Oops.  

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. 

SNAP, the Supplemental Nutrition Assistance Program, is funded by Title IV in the farm bill, currently under consideration in Congress.   It accounts for about 80% of the total farm bill funding, and costs taxpayers about $80 billion a year.

SNAP is an entitlement, which means that everyone who qualifies gets benefits—unless Congress changes that.  So far, all it is doing is trying to cut budget.

Although SNAP is under the Nutrition title, little about the program is designed to improve the nutrition and health of participants.  But the farm bill has plenty to say about nutrition—just not for SNAP participants.

Much of the Senate version of the Nutrition Title is about continued funding for food assistance programs other than SNAP:

• The Commodity Supplemental Food Program (CSFP)
• The Emergency Food Assistance Program (TEFAP) which mainly works through food banks
• The Department of Defense Fresh Program (fresh foods to schools and service institutions)
• Agriculture Marketing Service pilot programs in states for to source local foods
• The Senior Farmers Market Nutrition Program (coupon exchange at farmers’ markets, roadside stands, and community supported agriculture programs).
• A new Pulse Products Program that encourages sampling of a variety of beans and peas for use in school meal programs (I suspect some lobbying here).
• A Healthy Food Financing Initiative to administer loans and grants to improve access to healthy foods in “food deserts.”
• The Fresh Fruit and Vegetables Program to provide free fresh fruits and vegetables to low-income elementary school children
• Grants to eligible nonprofit organizations to improve community access to food through school gardens programs and urban greenhouse initiatives
• A new Service and Learning program funded at $25 million in which members work in K-12 schools to engage children in experiential learning about agriculture, gardening, nutrition, cooking and where food comes from. [Wow!  This one reads as if written to support FoodCorps—wouldn’t that be terrific!]
• Interagency taskforce to coordinate and direct programs that supply food to key nutrition programs like the Emergency Food Assistance Program and National School Lunch Program.

And here’s another one about the Dietary Guidelines for Americans of all things [whose bright idea was this?]:

• Not later than the 2020 report [the Dietary Guidelines for Americans] and in each report thereafter, the Secretaries [of USDA and HHS] shall include national nutritional and dietary information and guidelines for pregnant women and children from birth.

The Senate bill does have one useful, if poorly funded, piece directed at the health of SNAP participants, and another aimed at retailers:

• Grants to expand the purchase of fruits and vegetables by SNAP participants through programs like “Double Up Food Bucks.”
• Requires retailers who accept SNAP benefit payments to stock a wider range of healthful foods.

The House bill does more or less the same with the addition of:

• Grants for eligible nonprofit organizations seeking and developing innovative ways to improve community access to healthy foods.

Small-farm activist Ferd Hoefner, policy director at the National Sustainable Agriculture Coalition, said the quarrel over SNAP could rupture a long-standing partnership of rural and urban lawmakers who supported farm programs on the one hand, and public nutrition programs on the other.

“Is this the end of the farm bill coalition?” Hoefner said.

Is it?  I wonder if we will ever have a Congress that puts a little vision into this bill and writes legislation to solve some of our country’s agriculture, poverty, and health problems, interconnected as they are.