Resources
Reference & tools
Background explainers and reference material.
Ashwagandha is a herb used in Ayurveda. The evidence is limited and short-term — and there are important safety cautions to know first.
Resources Collagen supplements: what the evidence saysCollagen is the body's most abundant protein. Here's what the evidence does and doesn't support about taking it as a supplement.
Resources L-lysine: what it is and what the evidence saysLysine is an essential amino acid you get from food. Here's what the evidence does and doesn't support about taking it as a supplement.
Resources Omega-3 and fish oil: what the evidence saysOily fish is recommended for omega-3s. For supplements, the heart-protection evidence is more mixed than the marketing suggests.
Resources Zinc: oral supplements, topical creams and what they doZinc is an essential mineral — but 'zinc' covers very different products, from oral supplements to barrier creams and dandruff shampoos.
Resources Brain health: keeping your mind wellWhat the evidence supports for keeping your brain healthy — and why the basics matter most.