Newswise — Does it feel impossible to keep from overeating certain foods? That may be no accident. According to Stacey Cahn, PhD, an associate professor of psychology at Philadelphia College of Osteopathic Medicine, one’s willpower is often no match for the technology behind those tasty treats. Dr. Cahn explains:

When it comes to processed food, people often can’t stop at “just one.” It’s not a question of willpower. In fact, in a contest between processed foods and “willpower,” the good money is on Big Food. That’s because the game is rigged: Processed foods have been deliberately engineered, through extensive research and testing, to maximize your cravings. Here’s how they do it.

CraveabilityIt’s “good business” to develop products people crave; food companies may spend up to half a billion dollars a year, every year, to develop products that we crave—and they have been so phenomenally successful at unlocking the code of craveability that the former Chief Scientist for Frito-Lay once confessed, “I feel so sorry for the public.”

It turns out, craveability includes many things, including the optimal color (we like our “cheesy snacks” bright orange), the optimal crunch (we like chips that “break” at 4 pounds of pressure per square inch) and the optimal ratio of sweetness and fat. We don’t actually taste fat, so much as feel it. This “mouthfeel” stimulates the “reward” areas in the brain, intensifying the “hedonic experience.” So we keep eating.

Vanishing Caloric DensityResearch shows that we’re much more likely to overeat processed foods than “whole foods.” Snack foods that have an airy, crispy texture like cheese puffs leave us particularly prone to overeating because of vanishing caloric density. As the snack somewhat dissolves on our tongues, our bodies don’t register those fat calories, so we still feel hungry, and we keep eating.

Sensation-specific SatietyOur brains eventually tire of a specific flavor, a phenomenon known as sensation-specific satiety. Alternatively, the “Smorgasbord Effect,” explains why we overeat at buffets – the multitude of different flavors keeps us from habituating to any single one. That’s why processed foods like nacho chips are engineered to contain a complex spectrum of flavors. So we keep eating. And while junk foods may lead to overeating, their unnatural ingredients may independently lead to weight gain.

A (Bad) “Gut Feeling”The high-fructose corn syrup common to “regular” soda may be even worse than sugar when it comes to hunger and obesity. Artificially sweetened beverages (ASBs) masquerade as a weight-conscious alternative under the label of “diet” soda, but a growing body of research suggests that the opposite is true. Even more so than regular soda, existing research has shown that consumption of ASBs is associated with metabolic syndrome (precursors to diabetes and heart disease) and obesity, particularly abdominal fat. This may be because our hunger cues rebound in response to experiencing sweetness without the expected corresponding calories, and/or because the artificial sweeteners negatively affect bacteria in the “gut.” Food additives common to processed foods also appear to disrupt our guts’ natural bacteria, further promoting obesity and metabolic syndrome.

The Smart PlaySoda and processed foods can be “gateway drugs” to overeating. So when it comes to managing weight, sometimes the best advice is the simplest. To quote journalist and food activist Michael Pollan, “Eat Food. Not too much. Mostly plants.” Stack the deck in your favor by eliminating all sodas from your diet and choosing actual foods, rather than “edible food-like substances” to nourish yourself. A version of this piece, authored by Stacey Cahn, PhD, originally appeared on Philly.com: http://www.philly.com/philly/blogs/goal-getter-nutrition/Overeating-Its-not-by-accident.html