A Stack Worth Knowing About

Introduction

What does it really take to stay metabolically healthy in your 70s?

I ask myself that question most mornings. At 75, I've watched friends and patients slide into the slow decline that starts with a little extra belly fat, a fasting glucose creeping up, blood pressure drifting upward, and a heart working harder every year. Very few of them thought of it as a disease. They thought of it as aging. In many cases it's both, and the line between the two is thinner than most people realize.

Metabolic health is the soil everything else grows in. If your body can't handle sugar properly, can't use insulin the way it was designed to, or can't clear fat from your bloodstream, every downstream system pays the price. Heart, kidneys, brain, joints. I've seen it play out a thousand times in the emergency room.

The foundation of any change here is lifestyle. I'm going to keep saying that because it's true, and because I'm guilty of slipping on it myself. Real food that doesn't come out of a bag, some daily movement, sleep you actually protect, stress that you release instead of bottle up, and a spiritual life that grounds you in something larger than the next meal or the next worry. You can't out-medicate bad habits. I've tried to cover for mine with vitamins, peptides, and good intentions, and it doesn't work.

What's changed in the last few years is that medicine has finally produced a few tools that genuinely add to what lifestyle does, working alongside the foundations rather than replacing them. Three drug classes in particular, when used together in thoughtful patients with the right risk profile, appear to shift the trajectory of cardiovascular and kidney disease in a way we haven't seen before. Some of my colleagues are calling this a real shift in how we think about metabolic disease, and I think that's fair.

Forgive me, I'm going to get technical for a while. I want to walk you through what these drugs do, what the data actually shows, and what the choices look like in practice. Think of this as an introduction, not a prescription pad. Nothing that follows is something you'd do on your own. These are prescription medications with real side effects and real monitoring requirements. You do this with a Sage Matters coach or your own medical provider beside you, with labs before you start and labs along the way. With that in mind, let's look at the science.

The three drugs, and why they work better together

The stack people are talking about is metformin, a GLP-1 receptor agonist such as semaglutide or tirzepatide, and an SGLT2 inhibitor such as Jardiance or Farxiga. Three medications that hit three separate levers in your metabolism, with very little mechanistic overlap between them.

Metformin is the oldest of the three. It's been around for decades, costs very little, and works largely by changing cellular energy handling in a way that lowers hepatic glucose production and improves insulin sensitivity. AMPK, which you can think of as one of the body's low-fuel sensors, is part of that story, even if the full mechanism is more complicated than we used to believe.

GLP-1 receptor agonists work on a completely different system. GLP-1 is a gut hormone your body releases after you eat, and these drugs mimic and extend that signal. The result is better glucose-dependent insulin release, lower glucagon output, slower stomach emptying so you feel full longer, and meaningful benefits for weight, cardiovascular risk, and kidney outcomes in the right patients.

SGLT2 inhibitors work through the kidney. They block a transporter that normally reabsorbs glucose back into your blood, so some of that glucose is lost in the urine instead. That simple shift lowers glucose, changes fluid balance, eases blood pressure a bit, and reduces strain on the heart and kidneys. The heart failure and kidney data from this class have been one of the real surprises of the last decade.

So metformin is addressing insulin resistance and hepatic glucose output, the GLP-1 drug is addressing appetite and the gut-pancreas axis, and the SGLT2 inhibitor is offloading part of the glucose and fluid burden through the kidney. Three different jobs, three different targets, and that's exactly why the combination is more interesting than any one of them used alone.

What the data is actually saying

The numbers behind this combination have gotten stronger every year.

A systematic review published in Diabetologia in 2025 pulled together 18 cohort studies covering 1,164,774 patients. When GLP-1 agonists and SGLT2 inhibitors were used together, compared with either drug alone, there were lower rates of major heart events, all-cause mortality, cardiovascular mortality, heart failure hospitalization, and kidney composite outcomes. The authors were careful to note the limitation. These were observational studies, not randomized trials, so residual confounding cannot be ruled out. Still, the signal was large, consistent, and strong enough to justify randomized trials.

Real-world registry data tells a similar story. In one large cohort analysis, combination therapy was associated with the greatest reduction in all-cause mortality versus matched controls, with a hazard ratio of 0.25. In direct comparisons, the combination also beat either monotherapy, with hazard ratios of 0.53 versus SGLT2 treatment alone and 0.56 versus GLP-1 treatment alone. That is not proof of causation, but it is the kind of pattern that gets my attention.

An actuarial analysis published in Circulation modeled a different three-drug strategy, an SGLT2 inhibitor, a GLP-1 agonist, and a nonsteroidal mineralocorticoid receptor antagonist, in patients with type 2 diabetes and albuminuria. For a 50-year-old, the projected gain in major cardiovascular event-free survival was 3.2 years. That is not the exact stack I'm describing here, but it is a useful reminder that thoughtfully combined therapies can add meaningful healthy time, not just move lab values.

Metformin is the least studied of the three in these modern combination analyses, and we should say that out loud. A 2025 meta-analysis found that SGLT2 inhibitors and GLP-1 agonists reduce major cardiovascular events whether or not the patient is on metformin. The newer drugs stand on their own merit. Still, metformin has a rational place in the stack. It's inexpensive, familiar, and it addresses hepatic glucose production and insulin resistance in a way the other two do not fully cover. The longevity claims for metformin in humans still aren't proven the way I'd want, but as a low-risk, low-cost addition, it remains a sensible piece.

The SGLT2 inhibitors, drug by drug

This is the class that confuses people most, because there are several approved agents and the differences actually matter.

Empagliflozin, sold as Jardiance, at 10 mg or 25 mg once daily, has some of the broadest cardiovascular and kidney outcome evidence in the class. EMPA-REG OUTCOME established the cardiovascular benefit, and the EMPEROR trials extended that evidence into heart failure. In the triple-stack conversation, Jardiance is one of the most evidence-based choices. Pricing is still high without coverage, although manufacturer savings programs can reduce out-of-pocket cost substantially for some commercially insured patients. For glycemic control, the label does not recommend use below an eGFR of 30, although the heart failure and chronic kidney disease indications are broader.

Dapagliflozin, sold as Farxiga, at 5 mg or 10 mg once daily, has especially strong data in heart failure and chronic kidney disease, including in people who do not have diabetes. DAPA-HF and DAPA-CKD were the pivotal trials. In many heart failure protocols where diabetes is not the main issue, Farxiga is a very reasonable first choice. An authorized generic has also lowered the cash price in some settings. For glycemic control, the label does not recommend use below an eGFR of 45, though the heart and kidney indications are broader than that glycemic cutoff.

Canagliflozin, sold as Invokana, at 100 mg or 300 mg once daily before the first meal, was the first drug in the class, approved in 2013. Its strongest data is in diabetic kidney disease with albuminuria and in reducing cardiovascular events in established atherosclerotic disease. The old boxed warning about lower-limb amputation was removed by the FDA in 2020, though peripheral arterial disease still matters when you're choosing an agent. For a patient with type 2 diabetes and protein in the urine, it's still a reasonable option.

Ertugliflozin, sold as Steglatro, at 5 mg or 15 mg once daily, is the weakest fit for this particular conversation. VERTIS CV showed cardiovascular safety, but it did not show the broader superiority pattern that made the other agents so attractive. If the point of adding an SGLT2 inhibitor is cardiorenal protection, most clinicians will reach for Jardiance or Farxiga first.

Bexagliflozin, sold as Brenzavvy, at 20 mg once daily, was approved in 2023 for glycemic control only. It does not yet have cardiovascular or kidney outcome trial evidence. Its main virtue is cost. Through Cost Plus Drugs, it has been offered at a fraction of the price of the better-studied brands. For a lower-risk cash-pay patient who needs glucose control, that matters. For a high-cardiovascular-risk patient, the lack of outcomes data matters more.

Sotagliflozin, sold as Inpefa, is the odd one out. It blocks both SGLT1 in the gut and SGLT2 in the kidney, which makes it mechanistically different. The FDA approved it in 2023 to reduce cardiovascular death, heart failure hospitalizations, and urgent heart failure visits in adults with heart failure, or in adults with type 2 diabetes, chronic kidney disease, and other cardiovascular risk factors. It is not approved as a glycemic-control drug. Dosing starts at 200 mg and can be increased to 400 mg once daily before the first meal. In practice, Jardiance and Farxiga are still the more common first-line choices in this lane.

Practical things to watch for

A few points are worth flagging, especially for patients considering this combination for metabolic or longevity reasons without full-blown diabetes.

Hypoglycemia risk is genuinely low with these three drug classes when they are used without insulin or sulfonylureas. GLP-1 agonists stimulate insulin in a glucose-dependent way, SGLT2 inhibitors do not directly stimulate insulin release, and metformin rarely causes low blood sugar by itself.

Kidney function matters. Metformin is generally avoided below an eGFR of 30, and the SGLT2 inhibitors have agent-specific thresholds depending on whether you are using them for glycemic control, heart failure, or kidney protection. Anyone starting a stack like this needs baseline kidney function and periodic monitoring.

GI side effects are the most common complaint, mostly from the GLP-1 agonist and from metformin. Nausea, bloating, loose stools, and occasional cramping are the usual story. Extended-release metformin and slow GLP-1 dose titration both help.

Diabetic ketoacidosis is a rare but real risk with SGLT2 inhibitors. The risk goes up with prolonged fasting, surgery, dehydration, or very low-carbohydrate eating. If you're doing extended fasts or a strict keto diet, your prescriber needs to know that before one of these drugs is added.

Genital yeast infections are a known class effect of the SGLT2 drugs. You're spilling more sugar into the urine, and yeast likes sugar. Good hygiene lowers the odds, but it doesn't make the risk disappear.

The ADA Standards of Care for 2025 reinforced an important shift. In adults with type 2 diabetes and established or high cardiovascular risk, heart failure, or chronic kidney disease, SGLT2 inhibitors and GLP-1 receptor agonists are recommended for outcome benefit irrespective of A1c. In plain English, we no longer wait for the sugar to look terrible before using drugs that can lower heart and kidney risk.

What this actually means for you

I want to be careful here. This is a tool with real added benefit, not a silver bullet and not a shortcut past the foundations. If you aren't sleeping, moving, feeding yourself well, or taking your emotional and spiritual life seriously, a three-drug stack isn't going to fix what is actually wrong. I've been doing this for 40 years and I have never seen medication do the work that lifestyle does.

What I can tell you is that for the right patient, with the right risk profile, this kind of combination strategy can add healthy years and reduce major downstream complications. Much of the combination data is still observational, the randomized trials are still coming, and the long-term longevity question is not fully settled. We do not yet know what 20 years on a regimen like this looks like in someone who started at 55. What we do have are strong mechanistic reasons to think these drug classes complement one another and solid outcome data for cardiovascular and kidney endpoints, which remain some of the biggest drivers of how and when we die.

If any of this has you wondering whether it might apply to you, work with a coach or physician who understands the territory. Get baseline labs, including kidney function, A1c, a lipid panel, liver enzymes, and a urine albumin-to-creatinine ratio. Repeat them at thoughtful intervals and adjust as the numbers move. We are fellow travelers on this pathway, and the one thing I have learned is that patience and consistency, paired with real data about your own body, beat enthusiasm every time.

Every drug in this piece is prescription-only. None of it is something you order off the internet and titrate on your own. It's done with a physician who knows your history, orders appropriate labs, watches for side effects, and adjusts based on how your body responds. Individualization is everything. What's right for a 62-year-old with diabetes and an ejection fraction of 35 percent is not what's right for a 70-year-old with normal glucose and stage 2 kidney disease. If you're curious whether any of this applies to you, bring it up at your next visit, or come talk to us at Sage Matters.