A 21-year science story about sugar, sweat, and the surprising power of losing just 14 pounds.

Your body is basically a set of dominoes

Here's a fact that's interesting but not exactly cheerful: chronic diseases love company. When one shows up, others tend to follow, like party crashers who heard there were snacks.

Doctors have a word for this: multimorbidity. It just means having two or more long-term health problems at the same time — stuff like high blood pressure, heart disease, stroke, arthritis, kidney disease, lung disease, cancer, depression, dementia, and diabetes. Think of it as a buy-one-get-several-free deal nobody wanted.

And it's everywhere in older folks. Somewhere between 67% and 91% of Americans over 65 are juggling more than one chronic condition. More conditions means more pills, more appointments, more bills, and a lot less time doing the things you actually enjoy.

So scientists asked the million-dollar question: Can we knock the dominoes down before they start to fall?

The study that refused to end (21 years!)

Back in 1996 — when flip phones were fancy and the Macarena was somehow everywhere — the National Institutes of Health kicked off a big experiment called the Diabetes Prevention Program (DPP).

They signed up 3,234 adults at 27 sites across the U.S. Everyone had one thing in common: prediabetes. That means their blood sugar was higher than normal, but not yet high enough to count as full diabetes. It's the warning zone — the "we still have time to fix this" zone.

The scientists split everyone into three groups, totally at random:

Group 1 — The Lifestyle Crew. These folks got serious coaching: 16 one-on-one sessions in the first six months with real experts — nutritionists, exercise specialists, and behavior coaches. The plan was simple but specific. Eat better, cut calories and fat (aiming to trim about 700 calories a week worth of energy from their diet), get 150 minutes of moderate exercise a week (think brisk walking), and lose at least 7% of their body weight. For a 200-pound person, that's just 14 pounds.

Group 2 — The Metformin Crew. These folks took metformin, a cheap and trusted diabetes pill, twice a day.

Group 3 — The Placebo Crew. These folks took a sugar pill (fitting, right?) — no coaching, no real medicine. They were the comparison group, there to show what happens when you don't change much.

After about three years, the results were so strong the scientists actually stopped the experiment early — it felt unfair to keep some people on a sugar pill. The Lifestyle Crew had slashed their risk of getting diabetes by a jaw-dropping 58%. Metformin cut it by 31% — solid, but lifestyle clearly won the round.

Then came the twist: the scientists didn't stop watching. They followed these same people all the way to 2021. That's over two decades of check-ins, making this one of the longest health stakeouts in history.

The big new discovery: it was never just about diabetes

In June 2026, a fresh study published in the medical journal JAMA asked a bigger question. Forget diabetes for a second — did all that healthy living protect people from stacking up other chronic diseases too?

The researchers pulled Medicare records for 1,173 of the original participants (median age 74, mostly women) and tracked 15 different chronic conditions — high blood pressure, heart failure, clogged arteries, irregular heartbeats, high cholesterol, stroke, arthritis, asthma, cancer, kidney disease, lung disease, dementia, depression, diabetes, and osteoporosis.

Here's what they found, and it's a lot:

By the end, 85% of everyone had developed two or more chronic conditions. The typical person had five. Five! That's a calendar full of waiting rooms.

But the Lifestyle Crew did clearly better:

• 82% developed multimorbidity, versus 87% in the placebo group.

• They had a 21% lower risk of getting two chronic conditions, and a 25% lower risk of getting three.

• For the most expensive, most dangerous disease combos — like stroke plus kidney failure, or stroke plus heart failure — the Lifestyle Crew had a 43% lower risk. That's enormous, for both your health and your bank account.

Wait — what does "21% lower risk" actually mean?

Good question, because this trips people up. It does not mean lifestyle erased every disease. It means that, compared to the placebo group, the lifestyle folks were 21% less likely to stack up conditions over time. Diseases still happened — they just happened less often and tended to show up later. In the world of aging, "later and less" is a huge win.

And here's the kicker that surprised even the researchers: these benefits held up even when they removed diabetes from the list entirely. So the healthy habits weren't just preventing diabetes and calling it a day. They were quietly protecting people against a whole buffet of other diseases at the same time.

So what about metformin?

Let's be fair to metformin, because it's a genuinely great drug. It's been around for decades, it costs almost nothing, and it really does help prevent diabetes — especially in younger adults, people with a lot of extra weight (a BMI of 35 or higher), and women who had diabetes during pregnancy.

But in this study, looking at older adults and all chronic diseases? Metformin came up short. Its results (85% with multimorbidity) were basically a tie with the placebo group (87%). It's a sharp tool for controlling blood sugar — but it didn't deliver the broad, all-around disease protection that lifestyle changes did.

This isn't a total shock, either. Earlier research already showed metformin works less well in people over 60, even for diabetes alone. Different tools for different jobs.

Why does lifestyle punch so far above its weight?

The lifestyle program wasn't magic or some secret superfood. It was plain old science-backed common sense, delivered with structure and real human support. A few reasons it worked so well:

Losing a little weight does a lot. Even modest weight loss (7% of your body) calms inflammation, lowers blood pressure and cholesterol, and makes your body respond better to insulin. Weight loss was the single biggest factor in cutting diabetes risk.

Walking is weirdly powerful. That 150 minutes a week is just about 20 minutes of brisk walking a day. And get this: even people who didn't hit their weight-loss goal but did hit the exercise target still cut their diabetes risk by 44%. Sometimes showing up and moving is enough.

The habits stack. There's growing evidence that healthy behaviors work like a team. Eat well and move and sleep and skip the cigarettes, and the benefits add up to more than any single habit on its own. The DPP's whole-life approach wasn't one trick — it was several small ones working together.

Coaching beats a pamphlet. People didn't get a flyer and a "good luck." They got real coaches helping with real-life problems — how to eat well at a restaurant, how to stay motivated during a stressful week. Support is what turned good intentions into lasting habits.

The benefits actually lasted. Twenty-one years later, the effects were still showing up — probably because participants kept getting "booster" sessions and group classes to help them stay on track. Habits need maintenance, like a garden.

Oh, and the program was remarkably safe. No deaths were linked to it. The most notable side effect? More people reported sore muscles — which, let's be honest, is just proof they were exercising.

The modern plot twist: what about the new weight-loss shots?

Here's something the original 1996 study couldn't test, because the drugs didn't exist yet: the GLP-1 medications, like semaglutide (Wegovy/Ozempic) and tirzepatide (Zepbound/Mounjaro), that everyone's talking about now.

These drugs are stunningly good at preventing diabetes. In a three-year trial published in late 2024, only 1.3% of people with prediabetes taking tirzepatide progressed to diabetes, compared to 13.3% on a placebo — a 94% drop in risk, alongside major weight loss. Those numbers actually beat what lifestyle changes alone usually achieve.

So is the walk-and-salad approach obsolete? Not so fast. A few honest caveats:

The DPP study tested lifestyle, not these new drugs, so we can't directly say one beats the other in this experiment. They were different studies, with different people, measuring different things.

The shots only work while you take them. Real-world data shows that when people stop the medication, the benefits fade — and a lot of people stop. Persistence is everything.

We don't yet have 21 years of data on whether these drugs prevent the whole pile of chronic diseases the way lifestyle did. Lifestyle has the long-term track record. The drugs are still building theirs.

The likely future isn't pill-versus-walk. It's both — medication for people who need a powerful boost, layered on top of the eating and moving that keep the rest of the body healthy. The healthy habits never stop mattering.

Why you should care (the big-picture money part)

Multimorbidity isn't just a health headache — it's a giant economic one. More chronic conditions mean more hospital stays, more prescriptions, and bigger bills. In the U.S., chronic diseases eat up roughly 90% of the nation's $4.5 trillion yearly healthcare spending. That's trillion, with a T.

This study suggests something hopeful: a simple, safe, affordable program — started early, back when someone just has prediabetes — can lower the long-term pileup of disease. As the study's lead author, Dr. Marcel Salive, put it, very few things have ever been shown to prevent or delay multiple chronic conditions at once. This one did.

Your actual game plan (no clinical trial required)

You don't need to sign up for a 21-year study to steal these benefits. Here's the playbook:

Move your body. Aim for 150 minutes of moderate activity a week. Walk the dog, dance in the kitchen, take the stairs, pace while you're on the phone. It all counts.

Eat a little smarter. Trim some calories and fat. Lean on vegetables, fruit, whole grains, and lean protein. You don't have to be perfect — just a bit better than yesterday.

Lose a little. Even a 5 to 7% drop makes a real difference. For a 180-pound person, that's just 9 to 13 pounds.

Get screened. Health experts recommend diabetes screening for adults 35 to 70 who are overweight or have obesity. Catching prediabetes early is what gives you the chance to act before the dominoes fall.

Ask about the National DPP. The CDC runs a year-long, evidence-based lifestyle program in communities all over the country. Many are covered by insurance, including Medicare. It's literally this study, repackaged for real life.

The bottom line

A pill didn't pull it off. A 21-year study showed that eating better, moving more, and losing a modest amount of weight — with the right support — can meaningfully lower your odds of stacking up chronic diseases as you age.

It's not flashy. There's no slick brand name or viral ad. But it works, and the evidence is now stronger than ever.

Your body is going to get older no matter what — that part's not up for negotiation. But how many diseases tag along for the ride? That, it turns out, is at least partly your call. So lace up the shoes. Future you is watching.

This article is for general education and isn't medical advice. The lifestyle approach here is safe and effective for most people, but if you have prediabetes or other health conditions, talk to your doctor about the right plan for you — and ask about the CDC's National Diabetes Prevention Program, which many insurers (including Medicare) cover. If GLP-1 medications come up, they're powerful tools best prescribed and monitored by a clinician who knows your history, not bought from online clinics; the cluster's skinny-shot and weight-loss guides cover that landscape. Never start or stop a medication like metformin or a GLP-1 on your own.