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
SupplementsIron
The evidence is strong that iron supplements correct iron deficiency and anaemia: a Cochrane review of 67 trials in menstruating women found less anaemia, higher haemoglobin, better exercise performance and less fatigue.
2026-09-29 · 10 min read
SupplementsKava
Disputed. Kava is sold for anxiety, and the evidence is genuinely split.
2026-09-29 · 19 min read
SupplementsKefir and kefir grain cultures
Limited evidence. The evidence is limited.
2026-09-29 · 10 min read
SupplementsKratom
Disputed. There are almost no controlled human efficacy trials.
2026-09-29 · 13 min read
SupplementsL-theanine
The best-supported effect is narrow and short-lived: a single dose of around 200 mg improves one measure of attention in healthy adults within an hour.
2026-09-29 · 12 min read
SupplementsL-tryptophan
As a nutrient it is not optional; as a supplement the evidence is modest and the safety history is serious.
2026-09-29 · 18 min read
SupplementsL-tyrosine
The claim is that extra tyrosine supports thinking under pressure, and the review literature partly backs that while narrowing it sharply.
2026-09-29 · 18 min read
SupplementsLactase enzyme supplements
Lactase supplements reduce the hydrogen gas that signals undigested lactose and modestly reduce symptoms in trials.
2026-09-29 · 8 min read
SupplementsLacticaseibacillus paracasei and Lacticaseibacillus casei
Limited evidence. The evidence is strain-specific and limited.
2026-09-29 · 11 min read
SupplementsLactiplantibacillus plantarum
Disputed. The evidence is strain-specific and mixed.
2026-09-29 · 11 min read
SupplementsLacticaseibacillus rhamnosus GG
The best evidence is for reducing antibiotic-associated diarrhoea in children (moderate-quality pooled evidence); in adults the pooled result was not significant.
2026-09-29 · 11 min read
MedicationsLatanoprost
The evidence is that latanoprost reliably lowers pressure inside the eye, and that in one placebo-controlled trial this slowed the loss of visual field in newly diagnosed open-angle glaucoma over two years.
2026-09-29 · 13 min read
MedicationsLevothyroxine
Well established. It replaces missing thyroid hormone.
2026-09-29 · 15 min read
SupplementsLicorice root
Limited evidence. The best evidence concerns harm.
2026-09-29 · 11 min read
SupplementsLion's mane
The honest summary is that almost all of the biology behind lion's mane's reputation is cell-culture and rodent work, and the human evidence is a handful of small, short trials with inconsistent results.
2026-09-29 · 20 min read
MedicationsLisdexamfetamine
It raises brain dopamine and noradrenaline signalling through the dextroamphetamine released from it.
2026-09-29 · 20 min read
MedicationsLisinopril
Well established. Lisinopril lowers blood pressure.
2026-09-29 · 19 min read
MedicationsLoratadine
Loratadine blocks peripheral H1 histamine receptors, reducing the sneezing, itching and runny nose of allergic reactions, while penetrating the brain only minimally so it is comparatively non-sedating.
2026-09-29 · 11 min read
MedicationsLorazepam
Well established. Lorazepam sedates and damps down anxiety, and it stops seizures.
2026-09-29 · 14 min read
MedicationsLosartan
Well established. Losartan lowers blood pressure.
2026-09-29 · 21 min read
SupplementsLutein and zeaxanthin
Limited evidence. The evidence is limited and mostly about the eye.
2026-09-29 · 20 min read
SupplementsLycopene
Limited evidence. Less is established than the marketing suggests.
2026-09-29 · 15 min read
SupplementsManganese
Limited evidence. Manganese is essential, but deficiency is not a concern in people eating normal diets.
2026-09-29 · 9 min read
SupplementsMelatonin
Limited evidence. The honest summary is that melatonin's measured effect on sleep is real but small.
2026-09-29 · 18 min read