The human body functions optimally at a temperature of 20-25 degrees Celsius. Outside of this range, the body compensates through increased or decreased thermogenesis and sweating to maintain equilibrium.
Blood vessels dilate in the heat, resulting in a drop in blood pressure and reduced blood supply to the kidneys and liver. This leads to reduced urine output. In contrast, when it is cold, the contraction of blood vessels causes a rise in blood pressure. A healthy person’s body adapts very quickly to changed conditions, says Dr. István Barna.
The chief physician also notes that high temperatures above 25 degrees Celsius and temperature fluctuations significantly increase the risk of cardiovascular and acute kidney diseases, as well as mortality.
A wide range of symptoms can occur when the pressure in the blood vessels changes, including headaches, dizziness, weakness, and fainting spells in the case of high blood pressure. Higher temperatures can cause temporary congestion of the veins in the hands and feet, so it is important to drink plenty of fluids to help our bodies. The internist suggests drinking water instead of drinks that affect the sympathetic nervous system, such as Coke, energy drinks, or alcohol. He adds that, if possible, you should take your blood pressure, as the symptoms of low and high blood pressure can be similar.
“Compliant patients may be permitted a break from their medication by their doctor. Patients who regularly measure their blood pressure know which medication they will need to reduce if a warm front is approaching, to prevent their blood pressure from dropping too much and causing their heart to beat very quickly,” the doctor explains.
Blood pressure can be affected by temperature, height above main sea level, humidity, and air pollution. In some countries, it can also be affected by volcanic ash. Studies have shown that major sandstorms in Africa can increase blood pressure by 4–8 mmHg. – Dr. István Barna
The fact that a special working group was set up at the recent Congress of the European Society of Hypertension to investigate the effect of environmental factors on blood pressure and heart rate control demonstrates the relevance of this topic.
“We have conducted studies at Semmelweis University which have shown that blood pressure readings are 3–5 mmHg higher in winter and lower in summer. This should be taken into account when taking medication,” says the chief physician.
Dr. István Barna also points out that physical activity can reduce blood pressure by 4–6 mmHg in healthy people and by 6–7 mmHg in people with hypertension. In other words, activities such as hiking, cycling, walking, and yoga in the fresh air can only have a positive effect, as they ensure lower blood pressure in the long term. However, if a person’s body is sensitive to large temperature fluctuations, it is advisable to allow one to two days for adaptation before engaging in physical activity.
Orsolya Dávid
Translation: Judit Szabados-Dőtsch
Photo by Bálint Barta – Semmelweis University; cover: freepik.com
