8 “diet foods” boomers ate daily that we now know were anything but healthy

Diet culture has gone through some pretty wild phases.

Back in the boomer years, “health food” didn’t mean organic kale salads or kombucha. It meant products stamped with labels like low-fat, sugar-free, or diet.

These foods promised quick fixes—lose weight, protect your heart, stay slim—but looking back, most of them were Trojan horses for sugar, artificial ingredients, and empty calories.

The crazy part? A lot of these “diet” staples were everyday items, woven into routines like morning coffee or after-school snacks. People genuinely thought they were making healthier choices.

But as nutrition science evolved, the truth came out: many of these products weren’t much better than their “unhealthy” counterparts, and in some cases, they were worse.

Let’s dig into eight of the biggest culprits and see why they don’t hold up today.

1) Low-fat yogurt

For years, low-fat yogurt was marketed as the ultimate guilt-free snack. Boomers loved those little plastic cups, often with a swirl of “fruit” at the bottom that was more like jam than actual fruit.

The idea sounded smart—cut the fat, cut the calories. But when manufacturers removed the fat, they had to add something back to make it taste good. The answer was sugar. Lots of it.

Some of those “light” yogurts clocked in with more sugar than a candy bar. It was dessert in disguise, and yet people were spooning it down daily thinking they were nourishing themselves.

These days, we know better. Healthy fats actually help keep us satisfied, balance hormones, and slow digestion. That means full-fat plain yogurt (with probiotics intact) can be a much smarter choice than its sugar-loaded “diet” counterpart. Toss in some fresh fruit, and you’ve got a snack that’s both filling and nutrient-dense.

The lesson? Fat isn’t the enemy—it’s often the thing that makes food satisfying and prevents overeating later.

2) Margarine

Butter was practically villainized in the boomer era. Doctors warned it would clog your arteries, so margarine was touted as the “heart-healthy” alternative. Ads showed smiling families spreading it on toast as if they were avoiding a heart attack with every bite.

But here’s the problem: old-school margarine was made with partially hydrogenated oils—aka trans fats. And trans fats turned out to be far worse for cardiovascular health than butter ever was.

It’s a bit ironic. Boomers thought they were protecting their hearts, but in reality, margarine was a silent saboteur. It took decades before regulators started phasing out trans fats entirely.

Today, the narrative has flipped. Real butter, in moderation, isn’t the villain we once believed. Some nutrition experts even argue that grass-fed butter contains beneficial compounds like conjugated linoleic acid (CLA). Meanwhile, margarine as we knew it is basically a relic of the past.

3) Diet sodas

Diet Coke, Tab, Fresca—these drinks defined an era. Zero calories, zero sugar, and all the fizz. For many boomers, cracking open a can of diet soda felt like the ultimate diet hack.

The problem? Artificial sweeteners like aspartame and saccharin aren’t the miracle they were made out to be. Research shows they can confuse your brain and taste buds, keeping your sugar cravings alive. Some studies suggest they might interfere with gut health or insulin regulation.

And there’s the behavioral side too. When you drink six cans of diet soda a day, you’re not exactly building a foundation of health. It becomes a crutch—a way to chase sweetness without calories—rather than addressing the root habits.

Do I think the occasional Diet Coke is going to ruin your life? Probably not. But as a daily staple, it’s less “diet” and more “chemical experiment.”

4) SnackWell’s cookies

SnackWell’s were the poster child of the fat-free craze in the 90s. The green boxes lined supermarket shelves, filled with cookies people believed they could eat endlessly without consequence.

Boomers bought into the promise: no fat = no guilt. But the truth was, those cookies were highly processed, loaded with refined flour and sugar, and about as “healthy” as eating Oreos by the sleeve.

The psychology is fascinating, though. People often ate more of them because they felt they were safe. This became known as the “SnackWell effect”—when a food is marketed as healthy, people overeat it.

It’s a reminder that labels can trick us into forgetting the basics: cookies are cookies, no matter how you spin the ingredients.

5) Canned fruit in syrup

Those little fruit cocktail cups in school lunches seemed harmless—after all, fruit is fruit, right? The problem was the syrup.

A single serving of canned peaches in heavy syrup could deliver as much sugar as a soda. You got sweetness, sure, but very little of the fiber and nutrition you’d get from fresh fruit.

Boomers thought it was a clever substitute for dessert, but in reality, it was dessert. Today, dietitians encourage whole fruit because fiber is what slows down digestion, regulates blood sugar, and keeps us full.

Fresh fruit was always the better choice, but marketing made those syrupy cups look like a shortcut to health.

6) Instant diet shakes

If you lived through the SlimFast era, you probably remember the ads: “A shake for breakfast, a shake for lunch, and a sensible dinner.”

It was the ultimate quick-fix plan. And sure, drinking two cans of meal-replacement shakes a day could make the number on the scale drop. But it was mostly water weight, muscle loss, and calorie restriction.

The shakes themselves weren’t much better than sweetened chocolate milk. Loaded with sugar, artificial flavors, and not nearly enough protein, they left people hungry and unsatisfied.

Today, the shake trend looks different. Protein smoothies with leafy greens, nut butters, and seeds can actually fuel your body. But those old diet shakes? They were a shortcut that came at a cost.

7) Rice cakes

If you’ve ever bitten into a plain rice cake, you know they’re basically crunchy air. Back in the 80s and 90s, they were hailed as the ultimate low-calorie snack. Boomers would munch on them, convincing themselves they were staying slim.

Here’s the catch: rice cakes are mostly refined carbs with a high glycemic index. That means they spike your blood sugar quickly, leaving you hungrier than before. Pairing them with peanut butter or hummus helps, but eating them plain is basically dietary punishment.

The rice cake craze highlights a flaw in diet culture thinking: chasing “low calorie” instead of actual nutrition. A handful of almonds would have been more satisfying, even if the calorie count was higher.

8) Artificial sweetener packets

Coffee with pink, blue, or yellow packets was almost a ritual. Sweet’N Low, Equal, Splenda—they were the holy trinity of calorie-free sweetness.

At the time, sugar was seen as the enemy, so these packets looked like a miracle. But studies now suggest artificial sweeteners can disrupt gut bacteria, keep cravings alive, and maybe even trick the brain into expecting calories that never come.

To be fair, they’re not poison. But relying on them daily as a “healthier” substitute for sugar misses the bigger picture: retraining our palates to enjoy less sweetness is the real win.

Many people now opt for natural alternatives like stevia or monk fruit, or better yet, just learn to enjoy their coffee with less sweetness altogether.

The bottom line

Here’s the thing: boomers weren’t stupid. They weren’t trying to harm themselves. They were following the best advice available at the time. The problem was that most of that advice was driven by marketing, not science.

Food companies were quick to slap “low-fat,” “diet,” or “sugar-free” on products that were anything but nourishing. And because these foods were positioned as everyday staples, millions of people built their diets around them.

Looking back, it’s a reminder of how important it is to question health claims and look beyond the label. Nutrition isn’t about cutting one nutrient (fat, sugar, carbs) and replacing it with another artificial fix. It’s about balance, whole foods, and long-term sustainability.

The good news? We’ve come a long way since the boomer diet era. Today, we’re more focused on gut health, metabolic flexibility, and eating food that actually fuels us.

So the next time you see a shiny “low-fat” or “sugar-free” promise on a package, take a moment to ask yourself: does this food actually nourish me? If the answer is no, it probably doesn’t deserve a daily place in your diet.