A new study argues that eating meat in ‘old age’ may be as deadly as smoking cigarettes — only animal protein also seems to protect people from heart disease. Confusing? In a word, yes.
That’s because in our world of multimedia, 24-7 news cycles churning in an ocean of “infoglut” — the irrelevant, useless factoids in which we’re daily immersed — most of us never get past them.
We scan the websites, blog posts and, if you’re a real dinosaur, the newspaper, and absorb a few quick items without a whole lot of time or effort devoted to digging any deeper. That’s not a criticism of anyone’s intellectual curiosity, but rather a recognition of the sheer volume of information that confronts us each day.
Here’s a great example of how headlines can be misleading, this from CBS News online yesterday: “Meat, dairy may be as detrimental to your health as smoking cigarettes, study says.”
If you stopped right there, the implication is that bacon and eggs for breakfast, or a burger for lunch, is no different from firing up a pack of smokes. Indulge in either one, and you’re as good as dead.
The study, which was published in the journal Cell Metabolism earlier this week, claimed that middle-aged people who eat a diet high in animal proteins from milk, meat and cheese are more likely to die of cancer than someone eating a low-protein diet. The researchers further contended that people who ate lots of meat and dairy were more likely to die at an earlier age.
“The question is not whether a certain diet allows you to do well for three days, but can it help you survive to be 100?” the study’s co-author, Valter Longo, Edna M. Jones professor of bio-gerontology at the University of Southern California’s Davis School of Gerontology and director of the USC Longevity Institute, stated in a news release.
Of course, there’s more, much more, to the story.
Confusion and complications
Prof. Longo researches a protein that controls a growth hormone called IGF-I, which supports physiological anabolism—what we call “growth.” Highly elevated levels of IGF-I have been associated with an increased cancer risk, which makes sense, since cancer basically involves cells growing out of control.
Fine. But now here’s where it gets complicated. Allow me to quote from the study’s actual abstract to illustrate the complexity the news story’s headline utterly failed to capture:
“Mice and humans with growth hormone receptor/IGF-1 deficiencies display major reductions in age-related diseases. Because protein restriction reduces GHR-IGF-1 activity, we examined links between protein intake and mortality. Respondents aged 50–65 reporting high protein intake had a 75 percent increase in overall mortality and a 4-fold increase in cancer death risk during the following 18 years. These associations were either abolished or attenuated if the proteins were plant-derived.
That much of the abstract explains the headline, “Meat, dairy may be as detrimental to your health as smoking cigarettes.” A four-fold increase in the risk of death by cancer is nothing to take lightly, whether it’s from eating meat (allegedly) or sucking down cigarettes.
But let’s continue with the rest of the abstract, and see if you’re still crystal clear on what this research is actually suggesting, diet-wise:
“Conversely, high protein intake was associated with reduced cancer and overall mortality in respondents over 65, but a 5-fold increase in diabetes mortality across all ages. Mouse studies [also] confirmed the . . . detrimental effects of a low-protein diet in the very old. These results suggest that low protein intake during middle age, followed by moderate to high protein consumption in old adults, may optimize healthspan (sic) and longevity.”
So eating meat is bad, until you start cashing your Social Security checks. Then you should start spending that cash on all the meat and dairy products you used to try to avoid.
Does that advice make any sense? Foods that are unhealthy when you’re young and healthy suddenly become healthier as you become less healthy in old age? Really?
Granted, people tend to produce significantly less growth hormones after the age of 65, which is why many seniors tend to lose muscle mass over time. But what would you suppose might mitigate that loss of muscle tissue and the resulting decline in functional strength and mobility that accompanies it?
Eating a diet high in animal proteins, of course, as Longo himself acknowledged.
And here’s one more complication that renders meaningful conclusions so suspect.
In the study, the researchers reviewed 6,318 adults older than 50. On average, about 16 percent of their total daily calories came from protein. The “high-protein” eaters, the people supposedly four times more likely to die young, derived 20 percent of their daily calories from protein foods.
But what exactly is “high protein?” The Institute of Medicine, part of the National Academy of Sciences, recommends that adults consume 15 percent of calories from protein. Furthermore, resent research from the Institute showed that, “Increasing protein intake to 20 percent to 25 percent of calories can reduce the risk of heart disease, if the extra protein replaces refined carbohydrates, such as white bread, white rice, or sugary drinks. Higher protein diets can also be beneficial for weight loss, in conjunction with a reduced-calorie diet.”
So which is it? Eat more protein and avoid heart disease, still the No. 1 killer of American adults? Or cut down on protein and reduce the risk of cancer? Is that really the choice.
No, it’s not. Like all such consumption studies of “meat” or “dairy” or other broad dietary categories, the data are not only flawed by people’s skewed recollections of what they say they eat and what they actually consume, but “meat” doesn’t necessarily mean a serving of whole-muscle beef or pork sitting on a plate. Meat-eating typically means burgers or hot dogs in buns (and with fries) or deli meat in sandwiches with condiments — all involving the refined starches and added fats and sweeteners the Institute of Medicine recommends avoiding.
Not to mention all the tacos, pizza and fried chicken that people identify as “meat,” which are all loaded with those same fats and starches known to create health problems.
In the end, common sense makes the most sense, and pretending that otherwise healthy, nutritious foods people are encouraged to consume later in life could at the same time be bad news for younger, healthier people is, to cite a “meaty” example, baloney.
The opinions expressed in this commentary are solely those of Dan Murphy, a veteran food-industry journalist and commentator.