Research
Hormonal
Seasonal gene expression patterns in the immune system are inverted between the Northern and Southern hemispheres, indicating a photoperiod-driven circannual rhythm.
If you move from the Northern to the Southern hemisphere (or vice versa), your immune system's seasonal gene expression will invert to match the new local season, suggesting your body tracks daylight length to regulate immunity.
GoodSupportsHIGH confidence
We also find more than 4,000 protein-coding mRNAs in white blood cells and adipose tissue to have seasonal expression profiles, with inverted patterns observed between Europe and Oceania.
Why this rating
Replicated across multiple independent datasets from different hemispheres.
Source
Widespread seasonal gene expression reveals annual differences in human immunity and physiology
Xaquín Castro Dopico et al. · Nature Communications · 2015
DOI 10.1038/ncomms8000
cohortCited 534×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
More from this paper
- Human immune function exhibits significant seasonal variation, with a pro-inflammatory transcriptomic profile and increased circulating levels of risk biomarkers (sIL-6R, CRP) during winter months in temperate climates.Good
- The cellular composition of peripheral blood changes seasonally, with white blood cell counts and specific lineages (lymphocytes, monocytes, neutrophils) varying significantly by season in temperate regions.Good
Related findings · Hormonal
- Initial treatment for type 2 diabetes should be a combination of metformin and either an SGLT-2 inhibitor or a GLP-1 receptor agonist to achieve cardiorenal protection, rather than monotherapy or older agents like sulfonylureas.Strong
- For patients with specific monogenic obesity syndromes (leptin deficiency, POMC/PCSK1/LEPR mutations), targeted pharmacotherapy (recombinant leptin or setmelanotide) is highly effective and should be prioritized, unlike in polygenic obesity.Strong
- Continued weekly administration of 2.4 mg subcutaneous semaglutide prevents weight regain and promotes further weight loss in adults with overweight or obesity, whereas switching to placebo results in significant weight regain.Strong
This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →