What causes weight gain
If I ask you what constitutes “bad” eating, the kind that leads to obesity and a variety of connected diseases, you’re likely to answer, “Salt, fat and sugar.” This trilogy of evil has been drilled into us for decades, yet that’s not an adequate answer.
We don’t know everything about the dietary links to chronic disease, but the best-qualified people argue that real food is more likely to promote health and less likely to cause disease than hyperprocessed food. And we can further refine that message: Minimally processed plants should dominate our diets. (This isn’t just me saying this; the Institute of Medicine and the Department of Agriculture agree.)
And yet we’re in the middle of a public health emergency that isn’t being taken seriously enough. We should make it a national priority to create two new programs, a research program to determine precisely what causes diet-related chronic illnesses (on top of the list is “Just how bad is sugar?”), and a program that will get this single, simple message across: Eat Real Food.
Real food solves the salt/fat/sugar problem. Yes, excess salt may cause or exacerbate high blood pressure, and lowering sodium intake in people with high blood pressure helps. But salt is only one of several risk factors in developing high blood pressure, and those who eat a diverse diet and few processed foods — which supply more than 80 percent of the sodium in typical American diets — need not worry about salt intake.
“Fat” is a loaded word and a complicated topic, and the jury is still out. Most naturally occurring fats are probably essential, but too much of some fats — and, again, it may be the industrially produced fats used in hyperprocessed foods — seems harmful. Eat real food and your fat intake will probably be fine.
“Sugar” has come to represent (or it should) the entire group of processed, nutritionally worthless caloric sweeteners, including table sugar, high fructose corn syrup and so-called healthy alternatives like agave syrup, brown rice syrup, reduced fruit juice and a dozen others.
All appear to be damaging because they’re added sugars, as opposed to naturally occurring ones, like those in actual fruit, which are not problematic. And although added fructose may be more harmful than the others, it could also be that those highly refined carbohydrates that our bodies rapidly break down to sugar — white bread, for example — are equally unhealthy. Again: These are hyperprocessed foods.
In sum: Sugar is not the enemy, or not the only enemy. The enemy is hyperprocessed food, including sugar.
In the United States — the world’s most obese country — the most recent number for the annual cost of obesity is close to $200 billion. (Obesity-related costs are incalculable but could easily exceed $1 trillion annually. Wanna balance the budget? Eat real food.) The amount the National Institutes of Health expends for obesity-related research is less than $1 billion annually, and there is no single large, convincing study (and no small study will do) that proposes to solve the underlying causes of obesity. If the solution were as simple as “salt, fat, sugar” or the increasingly absurd-sounding “calories in, calories out,” surely we’d have made some progress by now.
We know that eating real food is a general solution, but a large part of our dietary problems might stem from something as simple as the skyrocketing and almost unavoidable consumption of caloric sweeteners and/or hyperprocessed carbs, which are in 80 percent of our food products.
Or it could be those factors in tandem with others, like the degradation of our internal networks of bacteria, which in turn could be caused by the overuse of antibiotics or other environmental issues. Or it could be even more complex.
The point is we need to know for certain, because until we have an actual smoking gun, it’s difficult to persuade lawmakers to enact needed policies. (Smoking gun studies are difficult in the diet world, but throwing up our hands in the face of complexity serves the interests of processed-food pushers.) Look no further than the example of tobacco.
Meanwhile, if we had to pick one target in the interim, caloric sweeteners are unquestionably it; they’re well correlated with weight gain (and their reduction equally well correlated with weight loss), Type 2 diabetes and many other problems. How to limit the intake of sugar? A soda tax is a start, proper labeling would be helpful, and — quite possibly most important, because it’s going to take us a generation or two to get out of this mess — restrictions on marketing sweet “food” to children.
There’s no reason to delay action on those kinds of moves. But let’s get the science straight so that firm, convincing, sound, evenhanded recommendations can be made based on the best possible evidence. And meanwhile, let’s also get the simple message straight: It’s “Eat Real Food.”
Mark Bittman is a columnist for The New York Times.