An appreciation of the factors that can boost your chance of hypothermia is important for your own safety and welfare in the wilderness. Recognising the chance or presence of these elements is one of the ‘softer ‘ abilities of remote country bushcraft.

Insufficient clothing has been implicated in several cases of hypothermia. Being wet through noticeably elevates your heat loss. Add to this inadequate or a complete lack of windproof clothing on a breezy day and you can rapidly envisage a disaster scenario.

Exertion leading to physical exhaustion is often a factor in the more major cases of hypothermia as it at last leads to a reduction in heat generation either through insufficient amount of energy and/or lack of activity. The level of your energy reserves is essential in fending off hypothermia. While your energy reserves remain untouched, you are more likely to be well placed to try hard enough to generate enough heat to make up for heat loss. Once your energy reserves are exhausted you can’t maintain your rate of work and heat supply falls and you succumb to hypothermia.

Inadequate food can decrease the fuel available for heat generation and in the short-term is closely linked to exhaustion. Particularly, low blood sugar has an adverse effect on your capability to stave off hypothermia. If your blood sugar is too low, it basically prevents you from shivering.

Over the long term, underfeeding (taking in less calories than you are burning) decreases your ability to maintain a standard temperature during exposure to cold. This reduces both subcutaneous fat and lean muscular mass. This decreases your body’s insulation and its ability to generate heat.

Subcutaneous fat (the fat layer under your skin) appears to have a repercussion on some people’s ability to stay warm in cold environments. there were cases where otherwise fit but highly thin people have succumbed to hypothermia while their companions have not.

Dehydration reduces your ability to do physical work. Physical work generates heat. Therefore if you’re dehydrated you might find it tougher to stay warm.

Injury and sickness both increase susceptibility to hypothermia and complicate the case of a hypothermic casualty. An injury may make the casualty less mobile and less able to generate warmth. Illnesses can interfere with your body’s temperature regulation. Vomiting and diahorrhea will make contributions to heat loss.

Sleep deprivation is thought to affect the body’s ability to regulate its temperature as the sleep cycle and other circadian rhythms are linked.

Age is also a factor. The young and the old are more prone to exposure hypothermia. Children have a higher proportion of body surface area to body mass than adults. Thus they get cold easier. Folks over 60 years old have a reduced ability to generate heat as their metabolism slows. Also their capability to limit warm blood flow to their skin reduces, probably causing increased heat loss.

Drugs can increase your proneness to the cold, either at once thru effect on your body or indirectly by having an effect on your mental state. Alcohol causes vasodilation, the exact opposite of vasoconstriction – and so increases heat loss by bringing warm blood near to the surface of your body. The increase in blood near the outer layer of your skin is why you go red in the face when you drink. Some prescription pharmaceuticals inhibit shivering. Alcohol or sedatives will dull psychological perception of the situation and the steps mandatory to cope with it such as putting on additional clothing or looking for shelter.

Hypothermia is one of the largest hazards in the wilds and an appreciation of the above contributing risk factors is vital in lessening the danger posed.

Paul Kirtley is head instructor at a Frontier Bushcraft. He is impassioned about nature, wilderness and remote travel. This is something that comes across exceedingly clearly on his bushcraft courses.