Issue 7 · August 6, 2026 · 5 min read
What happened when metformin was added?
The drug was added to a program that was already improving physical function
Researchers followed 114 older adults with obesity for six months. Two groups received the same supervised diet-and-exercise program. One also received metformin. The difference between those groups is the awkward part.
Tooth loss and memory: In more than 3,500 older US adults, total tooth loss tracked with a 50% higher risk of thinking problems within ten years. The link nearly disappeared among people who still saw a dentist.
A big nudge, a small move: A remote exercise program reached nearly 50,000 older women. Nine years later, they reported 3% to 4% more activity. The data were self-reported.
A pandemic that never left: Men exposed to the 1918 flu as young children died seven to eleven months sooner in old age. Exposure was estimated from deaths in their childhood cities.
The body came back, loneliness did not: Loneliness rose among more than 4,000 adults over 65 who lost mobility. Recovery stopped the rise, but did not reverse it.
Half as many deaths: A 20-year home stool-test program covered 2.2 million people in Spain's Basque Country. Colorectal cancer deaths fell by half in the screened group. Deaths fell nearly as much among the unscreened over-70s.
Steadiness matters: Across more than 11,000 people, larger blood-pressure swings between visits tracked with faster decline on a thinking-speed test, even after accounting for the average reading.
The gaps remain after 90: Among more than 800 people aged 90 and older, women faced nearly twice the dementia risk of men. Risk was also higher for Black participants than Asian participants.
Peanut tolerance from a capsule: Donor gut bacteria raised peanut tolerance in six of 15 people. There was no control group or blinding. A larger trial must confirm it.
The first mRNA flu shot: The FDA approved mFLUSIVA for adults 50 and over. It is the first licensed mRNA flu vaccine in the US. A confirming trial is still required for adults over 65.
Gene therapy keeps narrowing: Lilly dropped another program from its $1 billion Prevail acquisition. It is another sign of gene therapy's difficult economics.
Medicare goes national on hips and knees: The program is expanding nationwide, changing how hospitals manage care from surgery through recovery.
Most closures are not closures: Federal records show that most apparent nursing-home closures are ownership restructurings. The study tracked buildings and licences, not residents or care quality.
A public second thought: Bryan Johnson wrote that he may have taken his self-experiment too far. It is a reflection, not evidence about his protocol.
The Blue Zones argument, again: A thread claiming the Blue Zones rest on poor records and pension fraud passed 8.5 million views. The old critique concerns birth records, not diet.
Sinclair and Huberman disagree: David Sinclair says he takes low-dose tadalafil daily for brain and organ health. Andrew Huberman says he knows of no supporting data.
Featured
Metformin added 0.1 points
Metformin gets enormous attention in longevity. This trial tested it on top of supervised diet and exercise, not against nothing. Researchers assigned 114 adults aged 65 to 85 with obesity to three groups: supervised diet and exercise plus placebo, the same program plus metformin, or diet advice plus metformin. After six months the diet and exercise program had raised physical-performance scores by 2.5 points. Metformin added to that program moved them another 0.1 points, which could not be distinguished from chance. Use the same test on any add-on:
Added to what? Here, a supervised program that was already working.
Which outcome? Physical function over six months, in 114 people who were 89% men.
How much did it add? Here, 0.1 points, not distinguishable from chance.
What does it cost? Count money, side effects, monitoring, and attention.
This is not a verdict on metformin. The trial did not test it against nothing or study lifespan. The useful result is simpler: supervised diet and exercise improved physical function, and metformin did not show a clear added effect.
Try these four questions on one thing in your routine. If it is prescribed, discuss the answers with a clinician who knows your history.
More this week
Britain stopped rationing sugar in 1953, and those babies are still different
Britain ended sugar rationing in September 1953. That created a natural experiment.
Among more than 64,000 people born around the cutoff, those exposed to rationing during their first 1,000 days later had 36% to 69% lower rates of five cancers, slightly longer telomeres, and lower sugar intake five decades on.
The limit: this was not a trial. It does not show that cutting sugar now will do the same thing.
A rare variant in one gene tracks with the profile everyone is chasing
Researchers sequenced more than a million people. About 1 in 7,000 carried a rare variant that disables FNIP1.
Those people had less liver fat, lower blood sugar, healthier fat distribution, and about 60% lower odds of a combined measure of heart disease, type 2 diabetes, fatty liver and cirrhosis.
The variant is too rare to test for. Its value is as a drug-development clue: people appear to benefit when FNIP1 is switched off.
On the radar
A 79-year-old patient received special access to retatrutide, an obesity drug that is not approved. Six weeks later, Lilly said other patients may apply. Watch whether pre-approval access becomes routine. Lilly's filing has slipped to early 2027.
Go deeper at longevity.io