From Memios
The Longevity Letter
Practical writing and video on living strong and active into your 90s. No hype, no supplements to sell. Just what the evidence supports and what it looks like on an ordinary Tuesday.
579 items
SupplementsCannabidiol
The evidence is strong and narrow: purified pharmaceutical cannabidiol reduces seizure frequency in two rare epilepsy syndromes in placebo-controlled trials.
2026-09-30 · 16 min read
SupplementsCarnitine
Disputed. The honest summary is that the evidence is contested.
2026-09-30 · 22 min read
SupplementsCascara sagrada
Cascara is taken to force a bowel movement, and the plants that carry these anthraquinones are put into supplements for bowel function. The state of the evidence is the important part: in this search we could not reach or verify a single controlled human trial of cascara on its own, so its laxative effect rests on tradition.
2026-09-30 · 15 min read
ResearchWhat causes constipation, and why do some people get it more than others?
The evidence is strongest for the definition and for who is affected: pooled prevalence of functional constipation by Rome IV criteria is about 10% of adults, roughly twice as common in women.
2026-09-30 · 19 min read
SupplementsGerman chamomile
The best evidence is for anxiety rather than sleep, and it is thin. A randomised placebo-controlled trial in 57 people with mild-to-moderate generalised anxiety disorder found a greater fall in Hamilton Anxiety scores with chamomile (P = 0.047).
2026-09-30 · 13 min read
SupplementsCholine and citicoline
Choline's necessity is well established, while the supplement claims made for citicoline are not.
2026-09-30 · 16 min read
MedicationsCitalopram
For acute major depression in adults the randomised evidence does show an effect over placebo, but the effect is modest and the trial base is mostly industry-sponsored and at high risk of selective reporting.
2026-09-30 · 26 min read
SupplementsCocoa flavanols
The best evidence is a Cochrane review of short trials (2 to 18 weeks) finding a small drop in blood pressure of about 2 mmHg, rated moderate quality.
2026-09-30 · 12 min read
SupplementsBovine colostrum
Limited evidence. The best evidence is for two narrow things and it is not strong evidence.
2026-09-30 · 15 min read
SupplementsCranberry
Disputed. The best evidence is a 2023 Cochrane review of 50 randomised trials.
2026-09-30 · 16 min read
SupplementsCreatine monohydrate
Creatine is one of the few supplements where the exercise evidence is strong rather than suggestive: meta-analyses of randomised trials show small-to-moderate added gains in lean tissue and strength when it is combined with resistance training, and a European regulator has accepted a cause-and-effect relationship for repeated short, high-intensity efforts.
2026-09-30 · 18 min read
MedicationsCyclobenzaprine
The best evidence is a meta-analysis of 14 placebo-controlled back pain trials: cyclobenzaprine beat placebo for global improvement (odds ratio 4.7, 95% CI 2.7 to 8.1).
2026-09-30 · 23 min read
SupplementsDandelion
Not enough research to say. Most of the evidence is from animal and cell studies.
2026-09-30 · 8 min read
SupplementsDevil's claw
Devil's claw is used for musculoskeletal pain. A Cochrane review of herbal medicine for low back pain found that standardised daily doses of 50 mg or 100 mg harpagoside may reduce pain more than placebo.
2026-09-30 · 12 min read
MedicationsDoxycycline
For the uses where randomised evidence exists the effect sizes differ a lot by condition. Randomised placebo-controlled trials give it a protective efficacy of 84% to 96% against Plasmodium falciparum infection when taken daily for malaria prophylaxis.
2026-09-30 · 17 min read
FastingEarly time-restricted eating
Limited evidence. Evidence is limited to a handful of small or short trials.
2026-09-30 · 8 min read
MedicationsEmpagliflozin
Large placebo-controlled outcome trials, all funded by the manufacturers, show fewer heart failure hospitalisations and cardiovascular deaths in heart failure (reduced and preserved ejection fraction).
2026-09-30 · 13 min read
SupplementsEphedra
Ephedrine is a mixed sympathomimetic: it releases noradrenaline and stimulates alpha and beta receptors, raising heart rate and cardiac output, constricting blood vessels.
2026-09-30 · 14 min read
MedicationsEstradiol
The best evidence is that systemic estradiol reliably reduces hot flushes and night sweats and reduces fractures.
2026-09-30 · 22 min read
MedicationsEthinyl Estradiol; Norgestimate
The evidence strongly supports that this combination prevents pregnancy when taken as directed, and one brand (Ortho Tri-Cyclen) has trial evidence supporting an approved use for moderate acne.
2026-09-30 · 16 min read
MedicationsFamotidine
The evidence is strongest for what famotidine does to stomach acid and to ulcers caused by aspirin: in one 404-patient placebo-controlled trial it cut the rate of endoscopic gastric ulcers from 15.0% to 3.4% over 12 weeks.
2026-09-30 · 22 min read
Fasting48- to 72-hour fast
Evidence is very limited: small, short studies of cancer patients fasting around chemotherapy.
2026-09-30 · 10 min read
FastingFasting safety: who should not fast or needs a clinician first
Harms reported: hypoglycaemia with sulfonylureas and insulin, euglycaemic diabetic ketoacidosis with SGLT2 inhibitors, dehydration linked to SGLT2 inhibitors and diuretics, lean mass loss.
2026-09-30 · 14 min read
ResearchFecal microbiota transplantation (FMT): what it treats and what can go wrong
For recurrent Clostridioides difficile infection, a Cochrane review found FMT likely leads to a large increase in resolution (RR 1.92, moderate certainty).
2026-09-30 · 12 min read