Another St. Patrick's Day has come and gone. I used to look forward to the holiday for the excuse it gave me to bring home a magically delicious box of Lucky Charms. I'm not alone in having eaten the iconic General Mills brand as a grown-up. According to the Golden Valley-based manufacturer, nearly half of Lucky Charms consumers are adults. Not bad for a food invented by a man who chopped up Cheerios and Circus Peanuts candy, then doused it all in milk.

It's a cruel cereal. We've all felt the devastation when the marshmallows are gone and the bowl contains only oats and rainbow-colored 2 percent. Yet General Mills moves millions of boxes of Lucky Charms each year. Its sales — over $250 million in 2013 — are still rising in a cereal market that's slumping.

Add in the hundreds of millions General Mills earns each year from Cinnamon Toast Crunch, Honey Nut Cheerios and their pre-sweetened label mates, and the local food giant is likely taking in more than a billion dollars a year from products pitting toddler against parent in cereal-aisle meltdowns. On some grocery floor somewhere, a child is scissor-kicking his vote for a Big G brand as we speak.

All of this robust economic activity comes with a cavity — oops, I meant caveat — a coming economic, public-health and public-relations catastrophe with our fingerprints all over it. Thanks to our four-pronged relationship with sugar — via agriculture, commodity sales, food production and industry-sponsored food science — Minnesota has done as much as, if not more than, any other state to foster the global diabetes epidemic.

Our exposure to approaching policy changes, taxes and cultural stigma attached to sugar production will be high. We need to plan for the post-sugar economy, and we need to start now. The Mayo Clinic has yet to remove its candy, soda and juice machines. We need to talk about Lucky Charms.

Lucky Charms is 37 percent sugar. Its original recipe — Cheerios plus candy — failed to take off until the company coated the oat pieces in more sugar. The General Mills pre-sweetened line may be modest in comparison to the high-purity product coming out of the Kellogg's and Quaker Oats cartels, but much of it contains at least 9 to 10 grams of the white stuff per three-quarter-cup "serving." And that's after the company cut the crack in its cartoony brands in 2007 in order to continue advertising to kids.

The General Mills mascot for Lucky Charms cereal posed at the New York Stock Exchange before ringing the opening bell in 2011.

But halting your loading dose of any cereal at three quarters of a cup is wishful thinking. The FDA says we eat 30 percent more per sitting than that. The agency is being modest. Except for those nibbling breakfast from the food well of a Graco stroller, most of us serve up the Breakfast of Champions at double the listed amount. When it's the Breakfast of Leprechauns, others of us are like lab rats sipping sucrose from a dropper — we are going back for the reload. That makes an enthusiastic morning with this proud Minnesota product a 5-to-10-teaspoon bolus of the source of all illness.

That's what they're calling sugar these days. In case you haven't heard, sugar is on the way out, and its stock is diving just as many other forbidden foods are being rehabilitated: The ban on dietary cholesterol has been lifted. (Eat those eggs.) The case against saturated fat is crumbling. (Eat that butter, bacon and coconut oil.) "Calories in, calories out" is being depicted as Big Food misdirection. (Rent the documentary "Fed Up.")

But the case against two of Minnesota's leading agricultural products — sweeteners derived from corn and beets — only grows stronger with each passing holiday and the attendant aisles of seasonal candy insisting we get the party started.

In February, the 2015 Dietary Guidelines Advisory Committee (DGAC) proposed the Nutrition Facts panel be re-engineered to include all "added sugars" in a food in terms a person can actually understand (teaspoons). Currently, companies are allowed to disclose naturally occurring sugars and added sugars in a combined figure, hiding the sugars that matter most under the banner of total sugar, in grams. (Quick, someone who is not a drug dealer tell me what a gram looks like.) As a recent study by the Centers for Disease Control and Prevention concluded, however, a diet high in added sugars is an independent risk factor for heart disease whether you are overweight or lean. Clearly, we need to know that number, and in teaspoons.

The DGAC also requested our first-ever daily intake limits for added sugar, a suggested cutoff at 10 percent of daily calories. We currently get 15 percent of our calories as added sugar; the World Health Organization believes we should shoot for no more than 5 percent. Finally, the DGAC suggested that we protect American's health through the taxation of high-sugar drinks, as we do with tobacco taxes.

The food industry is fighting the proposed rule changes with everything it's got.

Tough talk from policy advisers is one thing. But even the bankers are getting nervous about sugar. In March, economists at Morgan Stanley issued a 70-page report titled "The Bitter Aftertaste of Sugar." It pointed at sugar as the perceived if not likely driver of a global diabetes epidemic affecting 400 million humans and counting. The report said our love affair with sugar could bring on "a reduced workforce and lower productivity (via premature deaths, exit from the labor force and/or poorer performance at work)," with the United States among the nations hit hardest.

The investment house said that if 20-year projections prove true, the economic future looked brightest in economies eating the lowest-sugar diets: Italy, France, Switzerland, Japan and Korea. Credit Suisse released a similar report in 2013, calling for taxation on sugary foods and drinks. Again, these aren't the worries of the food police; they are coming from people who work late and eat General Tso's chicken at their desk.

The X-factor

The arguments lambasting sugar come down to epidemiology and biology. As University of California pediatric endocrinologist Robert H. Lustig writes in "Fat Chance," sugar is very likely the X-factor behind heart disease, diabetes and hypertension. (He believes that sugar isn't a major contributor to obesity, only to the sickness we associate with it.)

Lustig's argument rests on two lines of evidence: our increasing consumption of sugar in conjunction with rising rates of diabetes, and the uniquely disease-promoting properties of sugar (a term in this article designating all added caloric sweeteners, whether sugar, high-fructose corn syrup, natural syrups or, yes, fruit juice).

First, the epidemiology: Americans eat roughly 22 teaspoons (or nearly a half-cup) of sugar each day, twice what we ate 30 years ago — and five times what we ate a century back. We consume this much sugar because half of us drink 10 teaspoons of it a day in the form of soda or fruit juice, and because if we eat anything with a label we simply have to eat sugar. Bread, salad dressing, ketchup, frozen food — under one of its 56 names, sugar is in everything. Caloric sweeteners are added to 80 percent of the 600,000 food products available in the U.S.

Using global food-supply data, Lustig recently examined the relationship between calorie type and the prevalence of diabetes. He found that total increase in caloric consumption did not predict diabetes, "but the correlation [between diabetes and] the percent of calories coming from sugar and sugar crops was enormous." A recent Journal of the American Medical Association analysis found a similar relationship between sugar consumption and heart disease.

Those are only associations — we need controlled dietary trials — but calories from sugar and juice are metabolized differently than are other calories or even other refined carbohydrates. That's because added sugar is both body-fattening (via the energy-storage hormone insulin stimulated by its molecule of glucose) and liver-fattening (thanks to its molecule of sweet-tasting fructose). Fructose is fine, says Lustig, when taken in whole fruit — fiber slows its absorption — but once industrialized, consuming fructose causes fatty liver disease after an easily surpassed maximum tolerable dosage, especially efficiently when fructose from sugar is taken in liquid form.

Fat in the liver creates inflammation in the arteries, lowers good cholesterol, and makes the small, dense LDL that accompanies metabolic syndrome and heart disease.

The new Kentucky

So it's official: Leading voices in a position to know have begun viewing sugar very, very badly.

Should it bother us that Minnesota is one of its very biggest purveyors? Look around. We may not be the home of Coke or PepsiCo, but a host of examples suggest that if sugar is the new tobacco, Minnesota is the new Kentucky.

Consider Cargill. In 2014, the global commodities behemoth announced an alliance with the Brazilian firm Copersucar, otherwise known as the world's largest sugar trader. The ensuing company was named Alvean, for "movement of white," and plans to coordinate the production and transport of raw sugar from ports and factories across the globe. The global sugar trade is 60 million tons.

Reading the firm's plan, mindful of its disease-promoting product — its Europe-based executives posed in sleek studio portraits in matching white shirts — all that's missing is Mike Myers as Dr. Evil, with a cat in one hand and his pinkie extended to his mouth.

Out in Golden Valley, General Mills is also dependent on the sale of sugar. (Sweetened products make up nearly one-fifth of its line, according to Morgan Stanley.) With its cereals, yogurts and prepared foods, the company has recently been paying for our "changes in eating habits," to use the corporate euphemism (another way of putting it: our "desire for survival"). The company recently shed 800 jobs, joining the retrenching underway at Kellogg's (2,000 jobs), Coke (3,900 jobs) and Pepsi (8,700 jobs).

But if Big G's move to lower the sugar in Yoplait was smart — the product was worse than a Krispy Kreme — by remaining low-fat and low-sugar, it was showing its preference for food marketing claims rather than food science. Take away the dairy fat, and people will want something sweet.

American Crystal Sugar and Minnesota beet and corn growers are in for a surprise when sugar becomes Public Enemy No. 1. With 24,000 sugar workers, Minnesota employs more people growing and making the stuff than does any other state; in the Red River Valley, beets pump $3 billion into the local economy.

Thanks to the farm bill, Minnesota plants more than 8 million acres with corn, a portion of which help flood the zone with cheap high-fructose corn syrup, a demonized ingredient that is arguably no worse than sugar, but surely no better, either. When diabetes spreads like the plague over the land, you have to figure those subsidies will be the first thing to go.

As for beets, we prop up their price with legislative heroics (U.S. Sens. Amy Klobuchar and Al Franken made sure of that in 2013). Price supports arguably keep sugar prices high, so their health consequences are limited, but they also prolong our dependency on a crop that will soon face tax penalties, label warnings, policy punishments and declining public favor.

Finally, the St. Paul campus of the University of Minnesota is home to an influential if less-well-known Minnesota link to sugar — the food-industry-funded Department of Nutrition and Food Science. (Currently, there is a General Mills Endowed Chair of Cereal Technology position available — for all who might be interested.)

If you are wondering why we are just now seeing the advice to include "added sugars" and upper limits for sugar on the Nutrition Facts panel, it's thanks in part to the fact that the last time the DGAC met, a food-industry-funded U nutritionist, Joanne Slavin, led the committee in charge of surveying the science on sugar. In keeping with the industry-preferred position, she views sugar as a "discretionary calorie" but no more harmful than any other calorie. The notion of sugar causing diabetes seemed to be off her committee's radar entirely.

Slavin, a registered dietitian with a doctoral degree, headed the Carbohydrate and Protein Committee for the 2010 DGAC. Following her October 2008 comments surveying the science of sugar and health, a committee member asked her whether they should be concerned about children developing diabetes from sweetened beverages.

"Is there data in children with [insulin] resistance and consumption of sweetened beverages?" she replied. "I think it's probably in those reviews if there was any data out there, but I don't have it off the top of my head." In an editorial published last May in the American Journal of Clinical Nutrition, Slavin called added sugar "the nutrition villain du jour."

"Added sugars are not the new trans fats," she wrote. "They are not the 'smoking gun.' " Studies linking sugar and diabetes do not represent "the body of evidence," in her view, and so the advice is always to move along, people, nothing to see here.

Both the nutrition and endocrinology fields have been unwilling to formally connect the dots with sugar and our health problems. Slavin offers the argument of a "dietary pattern" meme, one that says warning people about one ingredient (sugar) will only result in Americans eating foods rebuilt with refined carbohydrates and the calories that come with them. Their gaze, in other words, remains fixated on the early-20th-century dietary science of counting calories.

Which, like the search for four-leaf clovers, moons and rainbows at the bottom of a bowl of Lucky Charms, may have been a fool's errand all along. That sweet taste in your mouth, that's our problem.

Paul John Scott is a health-sciences writer living in Rochester. On Twitter: @pauljohnscott.