Archive · 2 Nov 2025
Cold Weather Linked to Increased Stroke Risk, Experts Warn
When it gets cold outside, your body's blood vessels squeeze tighter to stay warm.
This makes your blood pressure go up, and your blood can become thicker, like syrup.
Thicker blood is more likely to form clots.
If a clot blocks a blood vessel in your brain, it can cause a stroke.
Doctors notice more people having strokes when the weather gets cold, especially after holidays like Diwali.
People who are older or already have health problems like high blood pressure or diabetes are at even higher risk.
To stay safe, it's important to stay warm, keep moving, manage your health conditions, and know the signs of a stroke like sudden weakness or trouble speaking.
Cold weather significantly increases the risk of stroke due to vasoconstriction and blood thickening.
A 2024 study in The Lancet found cold weather poses a greater danger for stroke mortality than heat.
Every 1 degree Celsius drop below average temperature increases ischemic stroke incidence by 3.9% in the Indian population.
Individuals with pre-existing conditions like hypertension, diabetes, and older adults are most vulnerable.
Preventive measures include staying warm, indoor activity, regular health monitoring, and seeking immediate medical help for stroke symptoms.
- Who
- Neurologists and experts, including Dr. (Col) Joy Dev Mukherji, a neurologist at Max Super Speciality Hospital, Saket, New Delhi.
- What
- Cold weather is identified as a significant trigger for strokes, with studies indicating a notable increase in stroke risk and mortality during colder periods.
- When
- Annually, especially after Diwali, and with any sudden drop in temperature, even during summer.
- Where
- North India, and globally across 522 cities in 25 countries according to a study.
- Why
- Cold weather causes blood vessels to tighten (vasoconstriction), leading to higher blood pressure and thicker blood, which increases the likelihood of blood clots and subsequent strokes.
- Stroke Risk Increase per Degree Celsius Drop
- 3.9%
- Study Publication
- The Lancet (2024)
- Study Scope
- 522 cities, 25 countries
- Seasonal Trend
- Spike in stroke cases post-Diwali
- High-Risk Groups
- Individuals with hypertension, diabetes, heart problems, older adults (over 65), those in poorly insulated homes, people spending long hours outdoors in the cold, and those in low-income areas.