Ever since the second-coming of the Atkins Diet in 2003, carbohydrates have taken the blame for rising obesity rates. Before I go any further, let me make it clear that this country’s steadily rising intake of added sugars (which increased by 23 percent from 1985 to 1999, and currently clocks in at 156 pounds per year per person) has undoubtedly played a major role in the contribution of empty, and mostly liquid, calories that do not satiate and therefore do not discourage the consumption of additional calories.
However, the dangerous and inaccurate carb-phobia out there goes far beyond added sugars, vilifying all carbohydrates, essentially equalizing oatmeal with soda, chickpeas with donuts, and brown rice with Froot Loops.
If you hear some of the low-carb “authorities” like the infamous Gary Taubes (who in part supports his scientific theory on fruit being fattening by claiming that “if [he] eat[s] fruit, other than maybe a handful of blueberries a day, [he] start[s] to gain weight”), oatmeal and strawberries are just as responsible for obesity as Mountain Dew and chocolate donuts.
Mind you, this coming from a man with a background in applied physics and aerospace engineering who, to my knowledge, has never worked a day with patients in a clinical or outpatient nutrition setting, but instead makes conclusions and grandiose statements (and essentially says “everything we know about nutrition is wrong!”) based on reading copious amounts of scientific literature. Sure, he has acquired degrees from top-rated Ivy League universities, but in subjects that bear no relation to physiology, human biochemistry, public health, biology, or nutrition.
I wonder how the folks at NASA would feel about someone proclaiming themselves an expert on aerospace engineering (and telling them everything they know about engineering is incorrect) not because they actually had experience and an academic background with some semblance to the field, but simply because they had read piles of books on the subject for many years. Shouldn’t a relevant academic career and experience in a field that someone criticizes as being “dead wrong” count for something? Otherwise, why pursue a degree in a specialized field? Why work towards a credential? I digress. Let’s push that to the side, though, and examine the claims he and other “anti-carbers” make.
Interestingly, most vegetables — which are mainly comprised of carbohydrates — are exempt from harsh criticism, demonstrating how loosely and inaccurately the word “carbohydrate” is thrown around (anti-carb advocates generally use it to mean “grains and fruit”, though some go as far as shunning all beans due to their starch content.)
Speaking of starchy foods: this past Wednesday, a new Harvard study declared that ALL potatoes — no matter how they are prepared — are to blame for weight gain (according to that study, a baked potato and a French fry are equally responsible for added pounds). In fact, one serving of potatoes “was found to cause more weight gain than downing an additional 12-ounce can of a sugary drink or taking an extra helping of red or processed meats.” The Los Angeles Times article which reported this study also featured this jaw-droppingly ignorant “understanding” of nutrition:
“Making matters worse, potatoes pack a lot of calories into a relatively small package, said Dr. Dariush Mozaffarian, the study’s lead author. A large baked potato — without any fixings — will set you back about 278 calories, and a serving of French fries contains between 500 and 600 calories. That makes the 140 calories in a 12-ounce can of Coca-Cola or the 150 calories in a Pepsi look puny.”
This is what happens when we live in a society that gives exponentially more importance to weight than to health outcomes. By the logic (?) stated above, then, a can of soda is better than an avocado because it has fewer calories (70 fewer calories, to be exact). There is no mention of the fact that the large baked potato with its fiber and protein, is much more satiating than the empty calories in the can of soda. Or, for example, that the baked potato offers vitamin C, B vitamins, potassium, manganese, and an array of health-promoting phytonutrients. This caloric tunnel vision is the same nonsense trotted out by General Mills to “prove” that a serving of Trix is “better” than oatmeal due to a lower caloric content (I guess we’re supposed to ignore the copious amount of added sugar in the cereal).
Potato-phobia aside, let’s return to the “carbohydrates are making us fat” issue. A look at the historical data on carbohydrate intake makes it glaringly obvious that blaming all carbohydrates for current obesity rates is grossly misguided, to say the least.
This study from the American Journal of Clinical Nutrition, which displays average per capita intake of calories and macronutrients (fat, protein, and carbohydrates) in the United States between 1909 and 1997, is rather interesting, especially since it disproves much of the central arguments made by fervent low-carbers.
For starters, many in the low-carb camp like to make the statement that calories are irrelevant (according to them, calories from fat and protein “don’t count” because they do not lead to weight gain). This study shows that “until 1980, the total energy intake remained relatively constant. Then, between 1980 and 1997, energy intake increased by > 500 kcals/day.” And, wouldn’t you know, the early 1980s was when obesity rates began to rise.
Now, yes, approximately 80% of these extra calories came from carbohydrates. Specifically, that study points out that carbohydrates went from comprising 48 percent of the diet to 54 percent of the American diet. However, it also states that “from 1963 to 1997, the consumption of total fat increased nearly 30%, protein consumption increased 8%, and total energy consumption increased 9%.” So, really, we are looking at a caloric increase from all macronutrients.
Let’s take a closer look at carbohydrates, though. The “It’s the carbs, stupid!” advocates point out that, over the past fifty or so years, carbohydrate consumption in the United States has increased. Yes, absolutely. Set the clock back another fifty years and, well, the “blame the carbs” mentality doesn’t hold a lot of weight.
This chart shows average per capita carbohydrate intake in the United States from 1909 to 1997. Look at the average grams of carbohydrate consumed per capita in 1909. That’s right — exactly the same as 1997! Alas, the difference is in the quality of carbohydrates. Total grams of carbohydrates remained the same, but fiber intake plummeted. In other words, what happened after 1980 was an increase in two specific sources of carbohydrates: caloric sweeteners (i.e.: corn syrup, sugar, etc.) and refined grains.
But what about that Harvard study that claimed potatoes are fattening? Well, again — total potato consumption over the past 50 years has remained steady. However, according to figures by the United States Department of Agriculture’s Economic Research Service, “processed potatoes [mainly fries and chips] comprised 64 percent of total U.S. potato utilization during the 2000s (compared to 35 percent in 1960s).” So, once again, what we are looking at are higher intakes of highly processed, fiberless, refined potatoes.
Take a look at this map, culled from data by the United Nations’ Food and Agriculture Organization, which shows the contribution (percentage-wise) of carbohydrates in total dietary consumption around the world. Now, I should point out that the data is based on available food calories. So, for instance, The United States produces 3,800 calories per person, which is not the same amount that is actually consumed (some of these produced calories are wasted or exported).
However, intake data from the CDC matches these figures (that is to say, the contribution of carbohydrates in total dietary consumption based on food availability data is within one or two percentage points of data based on actual intake). Note, that the United States has one of the world’s lowest percentages of calories from carbohydrates. Now, compare that map with these two World Health Organization global obesity maps (one for males 15 and older, one for females 15 and older). There is absolutely no correlation between percentage of calories from carbohydrates and obesity rates. I am sure, though, that if one looked at consumption of caloric sweeteners and refined grains, the maps would look strikingly similar.
Two more things I want to mention before wrapping up:
1. Many in the low-carb camp employ the common “straw man” argument that if one does not condone the liberal eating of protein and fat while simultaneously shunning whole grains and fruit, then they are a “low-fat” drone who thinks people should start their day with a bowl of Corn Flakes, a slice of white toast, and a tablespoon of jelly, followed by a lunch of white rice and vegetables and a side of Jello, and a dinner consisting of two cups of refined spaghetti with a cup of fat-free marinara.
As readers of Small Bites know, I am far from a low-fat advocate. Is the American diet saturated with refined grains and caloric sweeteners? Absolutely. Is the American diet deficient in fiber? You bet. Should we lump all carbohydrates into one bag? No.
2. “But then why do people lose weight when they go on low-carb diets?”, some of you may wonder. No magic there — most people who go on low-carb diets simply consume fewer total calories than they did before starting the diet. Decreases in total caloric intake are why, every once in a while, the media revives one of those “man loses 30 lbs. eating nothing but (insert heinous fast food chain here)” stories. Weight loss is about caloric net loss. Of course, the key lies in achieving healthful weight loss and sustainable weight loss. Consuming 600 calories of Haagen Dazs — and nothing but 600 calories of Haagen Dazs — a day will certainly lead to weight loss, but it is also unhealthy and unsustainable.
As long as we continue to blame one nutrient for obesity, we are giving food companies ammunition to trot out more “low in (latest nutrient blamed for obesity)” stickers on the front of packaging for nutritionally-pitiful products that are better suited for a science fair exhibition than anyone’s pantry. What needs to be examined and brought to people’s attention is the increased intake of fake, refined, laboratory-made foods, the relentless advertising by food companies, and the agricultural policies that make added sweeteners and refined grains ubiquitous and cheap.