understanding health information starts with understanding the evidence behind it. this library is a practical guide to the different types of scientific evidence you'll come across, and how they relate to topics like seed cycling, hormone health and nutrition.
types of evidence, from strongest to weakest general reliability
systematic reviews and meta-analyses
these combine results from many individual studies on the same question, giving a broader picture than any single study alone. they are generally considered one of the most reliable forms of evidence, though they are only as good as the studies they include.
randomised controlled trials (rcts)
in an rct, participants are randomly assigned to a treatment group or a control group, which helps rule out other explanations for any differences seen. large, well-designed rcts are considered strong evidence, particularly when they are replicated by other researchers.
cohort and observational studies
these follow groups of people over time, or compare groups with different habits or exposures, without assigning treatments randomly. they can reveal useful patterns and associations, but they cannot prove that one thing directly causes another.
laboratory and mechanistic studies
these examine how a nutrient or compound behaves in cells, tissue or animal models. they help explain why something might work, but findings don't always translate directly to humans.
case reports and anecdotal evidence
individual stories and case reports can be a useful starting point for further research, but they are not proof that something works for people generally.
where seed cycling research currently sits
as we explain throughout our content, most of the evidence relevant to seed cycling currently comes from nutrient-level laboratory and observational studies, rather than large randomised trials of seed cycling as a complete practice. that means the evidence gives a reasonable rationale, but not proof of effect.
how to find credible sources yourself
- pubmed and google scholar allow free searching of peer-reviewed research.
- the cochrane library specialises in systematic reviews across many health topics.
- the nhs and who publish evidence-based guidance summarising current understanding for the public.
questions worth asking about any study
- how many people took part, and who were they?
- was there a control group?
- who funded the research, and could that create bias?
- has it been peer-reviewed, or replicated by other researchers?
our aim
we built this library so you can evaluate evidence yourself, rather than simply taking our word, or anyone else's, for what the research shows.