What the evidence says
Start with the thing you were wondering about. For each one: how many studies there are, how strong they are, and what they are.
Skin
Does collagen do anything for your skin?
Collagen
Thoroughly studied
22 studies in the archive
Is retinol worth it?
Retinol and retinoids
Thoroughly studied
11 studies in the archive
Does hyaluronic acid really hydrate?
Hyaluronic acid
Well studied
17 studies in the archive
Do peptide creams do anything?
Peptides
Studied in controlled trials
13 studies in the archive
Does vitamin C serum work?
Vitamin C
Well studied
5 studies in the archive
What does niacinamide actually do?
Niacinamide
Studied in controlled trials
3 studies in the archive
Does daily sunscreen slow skin ageing?
Sunscreen
Well studied
4 studies in the archive
What does Botox actually do to your skin?
Botulinum toxin
Thoroughly studied
11 studies in the archive
Is microneedling worth the money?
Microneedling
The evidence stops at small studies
14 studies in the archive
Do laser treatments work on ageing skin?
Laser treatment
Thoroughly studied
22 studies in the archive
Hormones
Is hormone therapy safe?
Menopausal hormone therapy
Thoroughly studied
53 studies in the archive
Do soy and plant oestrogens help with menopause?
Phytoestrogens and isoflavones
Well studied
14 studies in the archive
Hair
Does minoxidil regrow hair in women?
Minoxidil
Thoroughly studied
26 studies in the archive
Do finasteride and dutasteride work for hair loss?
Finasteride and dutasteride
Well studied
7 studies in the archive
Does platelet-rich plasma help thinning hair?
Platelet-rich plasma
Thoroughly studied
10 studies in the archive
Sleep and mind
Does melatonin actually help you sleep?
Melatonin
Thoroughly studied
11 studies in the archive
Does magnesium help you sleep?
Magnesium
Well studied
4 studies in the archive
Does ashwagandha do anything for stress and sleep?
Ashwagandha
Well studied
5 studies in the archive
How late can you drink coffee?
Caffeine
Thoroughly studied
7 studies in the archive
Is omega-3 worth taking?
Omega-3
Thoroughly studied
8 studies in the archive
Do you need a vitamin D supplement?
Vitamin D
Well studied
15 studies in the archive
Weight and lifestyle
What does strength training do after forty?
Strength training
Thoroughly studied
6 studies in the archive
Does the Mediterranean diet really help you live longer?
Mediterranean diet
Thoroughly studied
4 studies in the archive
This says how thoroughly something has been studied — not whether it works for you. What each study actually found is in the study itself, and in the plain-language write-ups we are adding.