In the documentary “Fed Up,” Katie Couric and Laurie David depict America’s sugar-saturated food system in ways that are at once startling and all too familiar. It reveals why Americans have such a hard time following the governmental advice to use sugar “sparingly.”

Over the last three decades, Americans have doubled the percent of their grocery budget directed toward sweets and processed foods (by 2012, those items represented nearly one-fourth of total household grocery expenditures). Of the 600,000 food items sold in the United States, 80 percent have added sugars (that go by more than 50 different names).

Food corporations spend millions calculating the precise “mouth feel” and “bliss point” that will entice people to return repeatedly to their brand. Recent brain research shows that the carefully mixed cocktails of sugar, fat and salt in industrial foods are highly addictive.

“Processed food is far more powerful than we ever realized,” observes former U.S. Food and Drug Administration Commissioner Dr. David Kessler in “Fed Up.” “Our brains are constantly getting hijacked.” Sugars stimulate the same pleasure responses in the brain as drugs and alcohol. A study with cocaine-addicted lab rats found that 40 out of 43 rats chose sugar water over cocaine.

Food corporations use this biochemical response to maximal advantage, exploiting our innate taste for sweet foods. Soda companies, writes Michael Moss in “Salt Sugar Fat,” refer internally to their most loyal customers as “heavy users,” suggesting that they knowingly cultivate sugar junkies.

The tactics that processed food manufacturers employ – paying for favorable research, discrediting critics, using deceitful advertising, and denying health risks – are similar to those tobacco companies used to get people hooked on cigarettes. And with good reason: Of the 10 vast corporations that control 90 percent of food produced in the United States (think Kraft, Nabisco, Coca-Cola, Pepsico, Nestle, etc.), several have been held by Philip Morris or R.J. Reynolds.

The U.S. Department of Agriculture supports processed-food manufacturers by subsidizing the production of corn (converted to high fructose corn syrup) and sugar. Repeatedly, Congress and the USDA have squelched nutritional reform efforts, opting instead to let the food and beverage industry “self-regulate.”

Thanks to corporate lobbying, sugar is the lone item on “nutrition facts” labels that has no recommended daily allowance. Similarly, soda manufacturers can call a 20-ounce bottle – typically guzzled at once – “2.5 servings,” and list a “serving” of Oreo cookies as “3.4 grams” (out of an 11.3 ounce package – good luck calculating how that translates to actual cookies!) Yet the labels don’t reveal more meaningful weights: Would people really feed their children Fruit Loops, Cap’n Crunch and Golden Crisp cereal if they knew those products were – by weight – between 40 and 52 percent sugar?

The food and beverage industry works hard to convince Americans that the alarming rise in obesity is not tied to their products, but is due to individual sloth and gluttony. Losing weight, they claim, is a simple balance of “calories in” (diet) matched by “calories out” (exercise).

Yet what the body does with those calories depends on their form. A handful of almonds may equal a can of soda in calories, but the liver and pancreas respond differently to real food because of the fat, fiber and nutrients it contains. Fructose in the absence of fiber is what pediatric endocrinologist Dr. Robert Lustig calls a “chronic, dose-dependent hepato (liver) toxin.”

Exercise can certainly regulate insulin, raise our metabolic rate and reduce stress. But it’s the rare individual who can expend the excess calories from junk food through greater activity (given that a 20-ounce Coke takes more than an hour of biking to burn off).

The industry’s “blame the victim” strategy has helped deflect public attention from the deleterious effects of junk food. Beset by advertising and confused by conflicting fad diets and fitness regimes, people reach for what’s cheap and close at hand – which tends to be highly processed foods and sweetened drinks. Americans now consume 3 to 5 times the daily limit of added sugars advocated by the World Health Organization (which recently lowered its recommended maximum to 25 grams or six teaspoons a day for an adult).

The result of this sugar saturation is a tidal wave of preventable ailments – diabetes, hypertension, cardiovascular disease, and certain cancers – which collectively account for 75 percent of current health care costs, the Centers for Disease Control estimates. These diseases threaten to overwhelm America’s health care system and undermine its economy.

Unconcerned about long-term societal costs, food corporations focus on short-term profits – collectively spending more than $36 billion each year in marketing. A third of that sum is targeted toward young people. Companies know that if they can get kids hooked on sugar early, they’ll have loyal customers for life (albeit perhaps a shorter life). The advertisers go after children, Michele Simon writes in “Appetite for Profit,” not only through television and social media but through product placement, movie tie-ins, “brand licensing” (like cartoon characters on cereal boxes), and even video “advergaming.”

Of course, there’s no better place to influence children than where they are a captive audience. More than three-fourths of the nation’s high schools have exclusive contracts with soft drink suppliers, “Fed Up” reports, and more than half have contracts to sell fast food. “The school system is where you build brand loyalty,” a CEO of Coca-Cola Enterprises admitted. In educational settings where young people should be getting habits for lifelong health, food conglomerates are allowed, in Simon’s words, to “exploit their vulnerabilities.”

“Fed Up” exposes a corporate food system tainted by rampant greed and immorality. It is indeed enough to make one sick.

Marina Schauffler, Ph.D., is a writer who runs Natural Choices (naturalchoices.com).