Siesta
A siesta is a habitual midday nap, usually after lunch, traditional in Spain and around the Mediterranean. A short one of about 30 minutes or less looks harmless or mildly helpful in Spanish studies; a long one tracks with higher weight, blood sugar and blood pressure in one Spanish study, though the obesity link fails to appear in some other cohorts. Either way, the long siesta is no longevity secret.
If you take a siesta, keep it to about 30 minutes or less. A long daily siesta is not worth adopting for health, and if you need one, ask why you are so tired.
Short siestas: harmless, possibly helpful
In a snapshot study of 3,275 Spanish adults, people whose siestas lasted 30 minutes or less had a 21% lower probability of high systolic blood pressure (the upper number) than people who didn't nap.[1] In a Spanish cohort of over 9,400 adults, a roughly 30-minute siesta looked protective against obesity.[2]
In Spanish adults aged 60 to 96, short napping went with about 17% lower mortality, while only naps beyond an hour carried higher mortality.[3]
Pooled studies are less reassuring. Napping of any length, compared with not napping, goes with about 19% more high blood pressure,[4] and one pooling of 20 cohorts found death risk rising with every extra minute of napping.[5] All of this is observational: it shows what goes together, not what the siesta causes.
Long siestas: a mixed and partly lifestyle-driven signal
In the same 3,275 Spanish adults, siestas longer than 30 minutes went with higher body mass index (BMI), waist size, fasting blood sugar and both systolic and diastolic blood pressure, and with 41% more metabolic syndrome (a cluster of heart and metabolic risk factors) than not napping at all.[6]
Part of the weight link came from what surrounds the nap rather than the nap itself: smoking accounted for about 12% of it, later sleep and meal timing for another 8% and 4%, and a larger lunch for 5%. Most of the association remained tied to the nap. The study measured everyone at one point in time, so it cannot say which came first.
Other cohorts disagree. In the Spanish cohort of over 9,400 adults, long nappers showed no excess obesity.[7] Across countries, the link between napping and obesity is strong in Spanish cohorts, modest in UK and US ones and not statistically significant in Chinese ones.[8] That suggests, though doesn't show, that the lifestyle around the nap (diet, smoking, late eating) matters more than the nap itself.
Beyond an hour, the risk figures climb for napping in general: about 30% more coronary heart disease, and more diabetes and obesity.[9] Naps of 90 minutes or more also disturb the following night's sleep. The thresholds are covered on Daytime naps.
Activity may change the picture
In those Spanish adults aged 60 to 96, meeting the standard activity guideline (at least 150 minutes a week of moderate-to-vigorous activity) appeared to buffer much of the mortality risk that came with short nights, long nights or very long naps; among those meeting it, no association remained.[10] The study measured how much people moved, not when, and is observational.
A possible mechanism, not a proven one
In people with high blood pressure, getting up from a siesta brings a blood-pressure surge similar to, though smaller than, the one on getting up in the morning.[11] That a daily surge leads on to insulin resistance and belly fat is a plausible guess, not a demonstrated chain.
Why the long siesta is no longevity secret
The siesta grew up alongside particular Mediterranean diets and social patterns, and it doesn't translate cleanly out of that context. Within those cultures a short siesta looks protective, but the evidence on long ones is mixed. The safe reading is that a long midday nap is, at best, not the source of any Blue Zone benefit.
What to do
- Keep a siesta to about 30 minutes or less, with an alarm. Don't drive straight after, and wait at least 30 minutes after a longer one that leaves you groggy (see Sleep inertia).
- Don't adopt a long daily siesta for health. The evidence on long siestas is mixed at best, and naps of an hour or more in midlife and later track with more heart disease and earlier death.
- If you find you need a long nap most days, look at your night-time sleep and get checked for sleep apnea.
How nap length, timing and age change the risk is covered on Daytime naps.
Further reading
- Vizmanos B et al. Lifestyle mediators of associations among siestas, obesity, and metabolic health. Obesity 2023.[12]
- Sayón-Orea C et al. Association between Sleeping Hours and Siesta and the Risk of Obesity: The SUN Mediterranean Cohort. Obes Facts 2013.[13]
- Duarte Junior MA et al. Associations of nighttime sleep, midday napping, and physical activity with all-cause mortality in older adults: the Seniors-ENRICA cohorts. Geroscience 2025.[14]
- Stergiou GS et al. Intraindividual reproducibility of blood pressure surge upon rising after nighttime sleep and siesta. Hypertens Res 2008.[15]