Our body temperature is maintained during the day and night by an in-built thermoregulatory mechanism which tries to strike a balance between internal heat production and environmental heat loss.
The normal body temperature ranges between 36.8 degrees Celsius and 37.2 degrees Celsius. When the body temperature falls below 35 degrees Celsius, a condition known as hypothermia (low body temperature) results; this is largely due to extreme cold conditions overwhelming the body thermoregulatory mechanism. It could also be due to the latter falling on its own.
Hypothermia can affect any body irrespective of age, sex, race or health status but the severity of its health effects is influenced by physiological and environmental factors.
The physiological factors include certain illnesses, old age, newborn/infants, sedentary lifestyle, poor acclimatization ability, inadequate thermoregulatory ability, medications, hard drugs, tobacco and alcohol.
The environmental factors include inappropriate clothing, inadequate housing with poor heating facilities and occupational or recreational exposure (outdoor workers, skiers). For outdoor workers, cold winds can easily bring down body temperature.
We can be exposed to cold through high velocity cold wind, winter cold, through water like being in the rain, immersion in cold water, wearing wet clothes for a prolonged period and to some extent, drinking very cold drinks. We can also be exposed to cold by direct contact with cold surface. When this happens, the body responds by generating heat through increased muscle activity such as shivering and exertive activities and also conserves heat by contraction of the blood vessels of the skin. If the responses fail to maintain the body temperature, hypothermia sets in.
Hypothermia (low body temperature) affects our respiration thus reducing oxygen supply to the body, it affects the functioning of the heart, it slows the circulation of blood and thickens the blood, it also affects our food digestion/absorption and our brain/nerves.
We must control our exposure to cold to live a long and healthy life
1. Respiratory diseases
Low body temperature narrows the respiratory tracts and increases the mucus secreted; this results in noisy breathing. Low body temperature increases the risk of chest infections, asthmatic attacks and chronic obstructive lung diseases. Cough is therefore common. Chest pain too.
2. Heart disease
Low body temperature from exposure to cold can cause irregular heartbeat, stroke, heart attack and other heart diseases involving the heart muscles and blood vessels.
3. Blood vessel disease
Low body temperature from exposure to cold can cause narrowing of the blood vessels to the skin resulting in changes in colour of the toes and fingers, numbness and tingling sensation in the fingers and toes. Pain is also felt in the fingers and toes.
4. Muscle/joint pains
Persons exposed to extreme cold may experience muscle pains and also joint pains. They complain of wrist pain (carpal tunnel syndrome), neck pain, chest pain, joint pain and stiffness sometime due to inflammation of the tendons.
5. Skin diseases
Skin rash (urticaria) is common when exposed to cold, the skin dries up and can be torn in some parts of the body especially the thighs. Thick oily creams help if applied liberally. Other skin conditions include psoriasis and atopic dermatitis. Sometimes the skin becomes red, itchy or pale. Occasionally, it accumulates water.
The well-known injuries from cold exposure include frost bite and trench foot; also fractures or head injury from falls
In temperate countries which experience winter, more deaths occur in winter than in any other season. The cold related deaths are due to heart disease, stroke and respiratory diseases.