How far do we need to go to avoid processed foods?

Q. I am trying to reduce the amount of processed foods in my diet, and I recently learned that soy milk is a processed food; which leads me to wonder whether cow's milk and other dairy products are also considered "processed"?   Would I be better off taking a supplement to get my vitamin D and calcium?

A. Yes, soybeans are cooked and pressed to make plain soy milk.  Commercially available cow's milk is skimmed, homogenized, and pasteurized. So, both are "processed." However, either one would be considerably less processed than a vitamin supplement, don't you think?

I think the movement away from processed foods is a great idea!  But if avoiding "processed" foods means that you need to take a vitamin supplement to supply missing nutrients, I think you may have missed the point of the exercise!

Cooked vegetables and pasteurized milk are technically "processed foods." And there are those who will argue that uncooked vegetables and unpasteurized milk are better for you. But I really don't think we need to go that far to improve the nutritional quality of most people's diets.

How do you define processing?

Think of processing as a spectrum.  On one end of the spectrum, you might have a raw ear of corn. On the other end might be corn chips. In its journey from one end of the spectrum to the other, the raw corn is cut off the cob, cooked, dried, ground, combined with sugar, salt, and fat, shaped into chips, and fried. 

We'd all immediately recognize corn chips as "processed" food. But where exactly do we draw the line between unprocessed and processed?  As soon as we cut the ear off the cob? When we boil it? When we grind it into flour? When we add sugar, salt, and preservatives? When we fry it? 

People are going to draw that line in different places.  Some might consider cooked corn OK but ground corn meal too processed.  I'd probably draw the line a step later, when the sugar, salt and preservatives are added.  But it's obviously somewhat arbitrary.  

A step in the right direction

Depending on how you want to define "unprocessed," a 100% unprocessed diet may not be practical. But every step you can take toward the "unprocessed" end of the spectrum is a step in the right direction. 

Michael Pollan proposes several humorous, common-sense guidelines in his recent books In Defense of Food and Food Rules, such as:

    1. Don't eat anything your grandmother wouldn't recognize.

    2. Don't eat cereal that changes the color of your milk.

Here are some other "food rules" that can help you shift your diet away from processed foods:

    3. Eat more food that comes without packaging.

    4. Look for foods with fewer than 5 ingredients in the ingredient list.

    5. Avoid things made with ingredients that you don't recognize as food.

    6. Eat more whole intact grains and less flour.

    7. Eat most of your fruit whole and unprocessed.

    8. Eat at least some of your vegetables raw every day.

What would you add?

Are "extruded" foods bad for you?

Q. I always thought Cheerios were really good for you; but I guess they are "extruded"?  How healthy are Cheerios?

A.  Many cereals, pastas, and snack foods are "extruded." That's not really as bad as it sounds. It simply means that grains are ground into flour, mixed into a semi-solid paste or dough and then squeezed through a tube or nozzle to produce a particular shape.  In the case of pasta shapes, like shells or penne, they are simply dried.  Cereals, crackers, and other foods may then be toasted or fried.

An extruded food can be made with whole grain flour, in which case it retains the bran and germ, or from refined flours.  It  may contain a lot of added sugar, fat, and/or sodium--or very little.  Cheerios are made from whole oats and are low in sodium and sugar. Compared to processed cereals that are high in sugar, I'd say they stack up fairly well. Still, for people who like to eat their food as close to nature as they can, Cheerios might be "too processed." 

There are a lot of things one could worry about vis-a-vis nutrition. I think we need to pick our battles.  If your diet is full of high-sugar, sodium, and trans-fat-laden processed foods, Cheerios might be the least of your problems! At the other extreme, if "extruded" Cheerios are the most processed food in your diet, I doubt they are doing much damage. But if your goal is a 100% unprocessed diet, then the Cheerios will have to go!

My goals for my own diet are a little more modest: If 80% of my diet is whole and minimally processed foods, I'm satisfied.

Trans fats and your metabolism

Last week, I answered a question from a reader who wanted to know if there was evidence to support the idea that processed foods could slow your metabolism.

In the popular imagination, the word "metabolism" is thrown around somewhat loosely. A "sluggish metabolism" might be invoked to explain anything from slow digestion to fatigue to weight gain. But when I hear "metabolism," I understand it to refer to how energy-efficient (or inefficient) the body is: How much energy does it take to maintain basic body functions?

For example, low thyroid function or long-term calorie restriction can slow your metabolism, or reduce your energy needs. Your metabolic rate (and energy needs) can go up following surgery or injury.  Now, there are certainly plenty of reasons to avoid processed food. But, as I wrote, I wasn't aware of research showing that processed foods affected metabolic rate, per se.

Over the weekend, however, I got a couple of interesting studies from readers, suggesting that certain components in processed foods could in fact impact metabolism.

One of the studies found that monkeys fed a diet high in trans fats gained more weight than monkeys fed a diet that contained the same number of calories but was high in monounsaturated fats.  The results suggest that large amounts of trans fats could, indeed, slow the metabolism.  Of course, the amount of trans fats in processed foods has been on a steep decline lately.  Still, processed foods are likely to be a primary source of trans fats in the modern diet.

Another reader pointed out research discussed by Gary Taubes and others suggesting that refined carbohydrates may have subtle effects on metabolism, mainly by reducing insulin sensitivity. Although I think the magnitude of this effect has been greatly exaggerated in the popular imagination, there is no denying that processed foods are often quite high in refined carbohydrates.

In short, readers have offered evidence of two reasonable mechanisms by which processed foods could affect metabolism.  Plus, evidence that you readers make this blog a far better resource than it would be without you!

Feeling stressed? Chocolate can help

It's no coincidence that Heart Health Month, Chocolate Lover's Month, and Valentine's Day are all celebrated in February.  It gives chocolate makers a great opportunity to remind us that the antioxidants in chocolate are good for hearts and sweethearts.

And the good news on chocolate just keeps piling up. Chocolate can lift your mood and ease emotional stress. Now, research shows that it actually reduces the biochemical impact of stress as well.  People who rated themselves as "highly stressed" ate an ounce and a half of dark chocolate every day. After two weeks, researchers found that that the level of stress hormones and other markers of stress in the subjects were reduced.  (See study.)

Online Surveys & Market Research

Do processed foods slow the metabolism?

Q. The Biggest Loser trainer says in her book that processed foods derailed her metabolism. Is there any credence to the theory (she offers no scientific evidence) that processed foods lead to a more sluggish metabolism?

A. Reminds me a little bit of the nutrition information offered by fashion models in the popular diet book, The Skinny Bitch.  My advice? Get your fashion advice from fashion models, your exercise advice from (qualified) fitness professionals, and your nutrition advice from a credentialed nutritionist or dietitian.

Processed foods may do a lot of things. (See for example this recent post on the link between processed foods and depression.) But I'm not aware of any evidence that they have any effect on the body's basal metabolic rate.  Could "sluggish metabolism" be a euphemism for constipation? As processed foods tend to be low in fiber and high in sugar and sodium, I could certainly see how they might be constipating! And I can think of plenty of other good reasons to cut them out of your diet without inventing any myths about their effects on "metabolism."

Will an anti-inflammatory diet help athletes?

Q. Would runners or other athletes benefit from following an anti-inflammatory diet?

A. Sure! But maybe not quite the way you're thinking.

An anti-inflammatory diet would benefit athletes as much as anyone--but it would be unrealistic to expect foods to counter inflammation due to injury or over-use.   Anti-inflammatory diets are helpful in suppressing the kind of chronic, low-level, systemic inflammation that leads to heart disease and aging. This type of inflammation is often caused or exacerbated by poor diet, obesity, and a sedentary lifestyle.

That's really a different kind of inflammation than the type likely to be experienced by runners.

There is research showing that anti-inflammatory diets can reduce systemic inflammation and disease risk factors. I'm not aware of any solid research that demonstrates an effect on athletic performance or recovery.

Bottom line: I believe an anti-inflammatory diet is a good choice for everyone. But if you're trying to bring down the swelling in an achy knee, you're better off with an icepack.

Flax versus hot flashes: It's a draw

There's good news and bad news from a recent study on flaxseed in post-menopausal women.

The bad news is that women eating 25 grams a day of ground flax seed for twelve weeks had no fewer hot flashes or other menopausal symptoms than women eating a placebo food. The good news is that both the flaxseed and the placebo groups reported fewer hot flashes!

It would have been interesting to have a third arm in the study--a group of women who got neither flaxseed nor a placebo food. That might have helped us tease out how much of the decrease was due to a  placebo effect--in which people's symptoms improve because they think they're being treated--and how much was simply the fact that hot flashes diminish naturally over time. 

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Snacks now account for a quarter of daily calories

Given today's obesity rates, findings from this study looking at trends in snacking behavior probably won't surprise you:

• Almost all adults now report snacking at least once a day (up from 71% in the 70s)
• We're also eating more snacks per day

And here's one that's especially disturbing:

• Snack foods have gotten more calorie dense (just what we need).

Americans now get a quarter of their daily calories from snacks. In addition, the total number of calories consumed has gone up. In other words, we're not snacking instead of eating meals. We're snacking in addition to meals.

Part of it is that we are surrounded by food everywhere we go.  It's also become socially acceptable to eat anywhere and everywhere: in class, in the car, on the bus, at the gym, in stores, and while walking down the street.  (My grandmother wouldn't have been caught dead eating in any of those situations.)

There's also a widely-held belief that it's best to eat every two or three hours. It all started with popular a diet concept that advocated six small meals instead of three large ones.  The problem is that people forget the "small" part. They snack religiously every two hours...in addition to three normal sized meals.

For more on this, I recently devoted two episodes of my weekly podcast to discussing why you do not need to eat every two hours and why you might be better off going longer between meals.

Maybe the old-fashioned "three meals no snacking" approach is worth trying again.  The grazing thing does not seem to be working out so well (except maybe for Auntie Anne's and Jamba Juice).

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Nutrition Data: Not an exact science

Every week, I get questions from users who are convinced that they've found an error on our site. I'm happy to chase these issues down because if there is an error, we want to correct it.  My first step is always to check the data on our site against the USDA's online database (which you can access here). In virtually every case, our site correctly reflects the USDA data. 

Of course, the USDA's database contains some errors. In fact, several errors in the USDA database have been corrected over years because ND users found them and I passed them along to the team over there. As a Nutrition Data user, you can take partial credit for improving the accuracy of our nation's nutrient composition data!

More often, however, it's a misunderstanding on the part of the user (i.e, wrong quantity, wrong food ID, etc.).  And sometimes, it's confusion about the nature of nutrient composition data.

From now on, I'm going to include a link to this article by Marion Nestle in my response to these sorts of queries. Nestle is responding to a question from a user, who (as it turns out) has misinterpreted the data. But Nestle then goes on to articulate several points that I am always struggling to explain to confused users.  She writes:

"Here’s the deal on food composition tables: you have to consider these numbers as ballpark figures, not as something engraved in stone.

• Foods grown and raised in different places under different circumstances have different nutrient compositions, so the food you are eating is unlikely to be identical to the ones tested by USDA.

• Nutrient amounts depend on weight; if your egg is a little bit bigger or smaller, the nutrient numbers change accordingly.

So you need to interpret food composition numbers leaving a lot of wiggle room.  That’s why I think reporting calories the nearest calorie is silly.  A 50-gram hard-cooked egg is 78 calories?  Plus or minus 10 maybe."

Sometimes I think the sheer amount of detail and precision here on Nutrition Data (nutrients reported to the hundredth of a milligram) seduces people into thinking that nutrition composition is an exact science. But as Nestle suggests, the nutrient composition database provides only an approximation (give or take 10%, perhaps) of what's actually on your plate.

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The Fifth Stage: Decline

An editorial in this month's Journal of the American Medical Association describes the four phases of the "epidemiological transition" that brought us into the modern medical age--and adds a depressing coda.

Here's the topline:

Phase 1: Pestilence and Famine.  Average life expectancy was 30 years during this phase, which stretched from the beginning of human history to late 19th century.

Phase 2: Receding Pandemics.  Industrialization in the U.S. and Western Europe in the late 19th and early 20th century led to better nutrition and sanitation, reducing infant mortality and increasing life expectancy.

Phase 3: Man-Made Disease:  In the middle of the century, smoking, reduced activity and changes in diet led to a peak in deaths from cancer and heart disease.

Phase 4: Delayed Degeneration:  Toward the end of the 20th century, preventive medicine and improved medical technology reduced early deaths from cardiovascular disease, effectively delaying illness and death to later years.

And now, the authors see a fifth phase emerging: The Age of Obesity, in which current and future generations face declining life expectancy due to complications of lifelong obesity. Obesity now causes more health problems than smoking or problem drinking. Yet, the authors write, "Unlike cigarette smoking, hypertension, and dyslipidemia, there is little consensus on the ideal approach to weight management...Failure rates are exceedingly high."

The statistics are depressing, for sure.  But the dire predictions are all based on things continuing according to current trends.  I'd like to think there could be another turning point in our near future. A Phase Six.    But what will drive it? Medical technology? Individual initiative? Public policy? Economic pressure?

What has the greatest power to turn the tide? What's most likely, given political and financial realities? I'd like to hear your ideas.

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