Last Monday the USDA released its latest version of the Dietary Guidelines for Americans (nominally dated “2010”). I was driving home and NPR carried USDA Secretary Tom Vilsack’s speech, in which he listed a few of the new highlights: eat less, eat less food with solid fats, eat less processed food, eat more vegetables and fruits, eat less sodium.
How much less sodium? About 2300 mg or 6 grams (1 teaspoon) of table salt per day, he said, is the recommended maximum for healthy adults, in line with the long-standing National High Blood Pressure Education Program’s guidelines, which are shared by the American Heart Association and many other professional medical groups.
There’s a second lower-sodium recommendation for anyone overweight, African-American, with heart or kidney disease or high blood pressure or diabetes, and anyone middle-aged or older. This year, as the more specifically heart-health-oriented professional organizations already recommend, the USDA guidelines set the lower maximum at 1500 mg per day, or about 3 grams of table salt.
And you’d think that was great, and I do, that the USDA guidelines have finally caught up with what the medical associations have been demanding based on the overwhelming weight of studies on dietary sodium intake as it affects blood pressure, cardiovascular disease including stroke, and kidney disease.
But there are two catches hidden in the midst of all this, and I’m not even sure Vilsack was aware of it. Smaller one first: Middle-aged? How old is middle-aged?
“Fifty-one and older,” Vilsack said. Whew, I thought. Four more years before I have to start thinking of myself as middle-aged. By the time I get there, I’m hoping the standard will have gotten fudged upward by at least another decade or so.
Because, you know, if you’re not 50 yet, 51 sounds reasonable–and comfortably remote for a lot of younger adults. Which I am, thank you very much. Don’t look at me like that.
So here’s Catch-51: When I was working at the National Heart, Lung and Blood Institute back in the mid-’90s, the general working recommendation for lowering sodium to 1500 mg/day was all the other high-risk groups Vilsack mentioned…and healthy adults 40 and up. Not 51 and up.
The choice of a cutpoint at age 40 for otherwise healthy people was based on the risk data from the first three National Health and Nutrition Education Surveys, which began collecting data across the nation starting in the 1970s. The latest version collected data around 2006 and its findings were just released last spring by the Centers for Disease Control. All the NHANES studies correlate in-depth interviews about diet, exercise and lifestyle patterns, and cardiovascular history along with clinical health measurements (height and weight, blood pressure, cholesterol, urinary sodium excretion, blood iron, etc.) from thousands of ordinary Americans. Even early on, there appeared to be an independent higher risk and a greater need to lower sodium at 40 and older, all other health risk factors being equal.
But of course 40 seems too young to be middle-aged. And the USDA, which issues the Dietary Guidelines for Americans, tends to downplay certain elements of the risk statements so that no one, or at least not the agency’s chief constituents, gets upset. The no one in this case might easily be the processed food and restaurant industries, which depend heavily on salting aggressively, and whose most reliable customers (other than for McDonalds, maybe) happen to be people in their 40s–people with money, jobs, children at home, a shortage of free time and a perceived desperate need for convenience foods.
Professor Marion Nestle has pointed out that some of the language in the new guidelines seems politicized to appease corporate partners and diffuse the effectiveness of recommendations that disfavor them. She contends the guidelines name specific foods for people to eat more of, but when it comes to restricting foods high in saturated fats, sugar, and salt, the language suddenly turns to chemical components rather than naming foods to avoid (like french fries, burgers, packaged baked goods, snack foods, pizza, cereals, and so on).
That would certainly be in line with what I heard from (often frustrated) scientific participants on the earlier USDA dietary guidelines committees, but I think by now people know what sodium is and are actually, thanks to the newer restaurant nutrition laws, starting to pay a little attention.
Back to the argument at hand here:
Forty vs. 51–what does it matter really? Especially if 90 percent of everyone is eating about 3400 mg of sodium per day at this point? Wouldn’t getting everyone down to 2300 or so be miracle enough?
It would, actually. My beef with the guidelines is that Americans don’t think of themselves as middle-aged at 40–they think they’re youngish still. Are they likely to start “moderating” their intake now unless they happen to have suffered an early stroke or heart attack? Not without a real push for awareness.
The 10 years between 40 and 50 are critical for just about everyone. That’s when both men and women start slowing production of estrogens and androgens, they start to lose collagen and flexibility in their joints and ligaments, and they start to build more abdominal fat. Most also begin to lose muscle and skin tone as well as bone mass. They start to increase their risk of heart attacks, stroke, kidney disease and Type II diabetes. They start to need blood pressure medications. So waiting until you’re over 50 to reduce your sodium intake could mean an extra 10 years of your body coping–badly–with the excess at a time when it’s already going through big changes.
But that’s not all that’s offtrack about the newest USDA guidelines on sodium. The 40 vs. 51 debate is really moot, given the more general state of American physical fitness at this point.
Here’s the second catch, the important one, Catch-2 if you will: The truth about lowering sodium aggressively is that it’s no longer really about who’s middle-aged.
About 70 percent of all adults in the U.S. are now overweight–yes, that’s the grim majority, even among hip young 20-somethings–and a third of all kids are too. The American Heart Association has come out and said that means just about EVERY adult should be aiming for 1500 mg/day, not 2300. And they shouldn’t be waiting until they’re 51.
Here the USDA appears to be using a euphemism, “middle-aged,” to downplay exactly when you need to start worrying about your salt intake. Worse, it’s listing the recommendation that’s relevant for most people second, as though it weren’t really all that important. And nowhere does the agency point out that the second one is actually the guideline for most people.
Considering how sound bites tend to go, you know the 1500-mg. recommendation is going to be dropped all too easily, while all the radio and tv announcers eagerly parrot a misleading and vague moderate-your-sodium-to-2300-mg. guideline that really only applies to less than one-third of American adults and isn’t very motivating.
But let’s say you’re not one of the overweight–lucky you. Let’s say you’re not African American, you’re not unfit, you don’t have any of the cardiovascular, diabetic, or kidney diseases, etc. etc. Let’s say your only worry is age because you’re no longer 39 and you’re wondering whether you should go with the general consensus among the major medical associations or the USDA’s less-upsetting one.
All I can say is, if you’re currently eating a “typical American diet” with 3400 or so mg of sodium per day, giving yourself an extra 10 years’ “benefit of the doubt” and waiting until you hit 50-plus could be a bad bet. Lowering the sodium in your diet starting now, even if you don’t achieve a 1500 mg. diet right away, could give you an extra 10 years of life. Maybe even 20, and if you throw in some light daily exercise, a lot less likelihood of spending most of it in a wheelchair with tubes taped to your nose. (And isn’t that an appetizing thought. No wonder the USDA shoved it under a rug.)
Check out the DASH Diet Basics page link above and get a free guide with charts, shopping strategies, meal suggestions, etc. from the NHLBI–to its credit the USDA has pointed out that DASH is very well-tested for lowering blood pressure, it’s versatile, and it’s relatively painless for cutting down on hidden salt and fat.
Filed under: cooking, DASH Diet, Diabetes, Eating out, Food Blogs, Food Politics, history, nutrition, shopping, unappetizing | Tagged: American Heart Association, cardiovascular disease, DASH Diet, Dietary Guidelines for Americans 2010, heart disease, hidden salt, high blood pressure, hypertension, low-salt, middle-aged, NHANES, NHLBI, sodium intake, stroke, USDA |