Peptides and longevity: what should you check in a paper?

What was actually measured?

A biomarker is a measurable characteristic of the body, such as the blood level of a particular substance. It can provide useful information, but a change in a marker is not the same as fewer illnesses, better physical function or longer life. [4]

When reading an article, name the outcome precisely. A physical performance test improved is more accurate than ageing was reversed. The latter claim would require much broader evidence.

What does the MOTS-c example teach us?

MOTS-c research assessed measures including mouse performance and survival. The overall survival curve showed no statistically convincing difference. The paper should therefore not become a claim of proven life extension. Its human part measured responses after exercise without administering the peptide. [36]

An animal experiment can be valuable while still leaving the question about humans unanswered. This is a normal stage of research. The problem arises when a description omits that stage and presents a hypothesis as an established benefit.

Which questions help assess a claim?

• Were humans, animals or cells studied?
• Did the study actually measure lifespan or everyday functioning?
• What was the comparison group?
• Was the follow-up long enough to assess harms as well?
• Have other teams reproduced the finding?

Participants' ages matter too. Results in young, healthy participants do not automatically describe the needs of an older person taking several medicines.

Where can you find a specific example?

View MOTS-c profile and discussion of its research. There we distinguish measurements of the natural peptide, animal experiments and a planned human trial. The article explains how to assess evidence; it is not a comprehensive review of all ageing research.

Where does this information come from?