The Effect of Coldness on the Body

Cold weather places physiological stresses on the body. Whether these stresses become harmful or beneficial depends on an individual’s ability to adapt. The more healthy and fit a person is, the easier it is for him or her to cope with these stressors. The proper use of clothing, avoiding undue stress, being seasonally acclimatized to the climate and good nutrition all contribute to a person’s ability to stay well in cold conditions.

Some diseases are more common in the winter than in other seasons. Among these are coughs and chest and lung illnesses, bronchitis and asthma, as well as heart and circulatory disorders such as vascular disease, thromboembolic stroke, and coronary artery disease. The risk of death from these conditions increases significantly with cold exposure.

Aside from its direct impact on these illnesses, cold weather also decreases the ability of immune system to fight illness by reducing blood flow to the extremities in order to preserve body heat at the core and the head. This in turn reduces white blood cell availability and diminishes the body’s ability to fight infection.

In the military, cold injury is one of the most common causes of combat casualties. During World War II alone, over 90,000 U.S. Army and 20,000 German Army personnel died of cold-related injuries. Today, cold injury is an area of major command emphasis for U.S. Army soldiers deployed in arctic and northern areas of the world.

Many people are more vulnerable to cold weather than others, such as the elderly and those with underlying health problems. Hypothermia can develop when the body’s internal temperature falls too low, which can cause permanent tissue damage and even death. Older people are particularly at risk for this because of their decreased circulation and the fact that they often do not dress in warm enough clothing. They are also at greater risk for cold-related illnesses and may not be able to recognize the symptoms of cold stress or the need for medical attention.

People who live in disadvantaged socioeconomic circumstances tend to be at increased risk for the effects of cold temperatures because they cannot afford adequate clothing or heating and do not have proper insulation in their homes. Poorly insulated households can lose heat more quickly than adequately insulated ones and can result in higher than necessary energy bills. Poorly maintained heating appliances can also cause carbon monoxide poisoning, which is more common on cold days than other times of the year. Cold temperatures also limit the range of biting organisms that carry diseases such as malaria, sleeping sickness (trypanosomiasis) and bilharzia (schistosomiasis). These are three of the most devastating and expensive human diseases in the world. Despite these benefits, the negative effects of the cold on health remain substantial and should not be ignored.