Beauty & the Heat: How Heat and Cold Effects the Skin
There are many factors that can both impact and affect our body temperature and should be considered during a consultation. It is essential that we understand the importance of heat loss and heat gain and how these temperatures are conserved within the human body.
To be able to maintain a healthy core body temperature, our bodies must have equality in its heat losing center and its heat promoting center. When one is stimulated, a concurrent inhibitory signal is sent to the other.
If the outside temperature is hot or if there is increased physical exertion which raises the body temperature above the set point, the activated heat losing center first inhibits the signal to muscle fibers lining blood vessels in the skin. This decreases our muscle tone, allowing the vessels to dilate and become flush with warm blood that is moved away from the core. Our skin acts as a giant radiator that offloads body heat to air currents that then either carry it away, transfers it to cooler objects or radiates it away as electromagnetic energy. Excess heat causes stress on vessels, altering heat schock protein content, endothelial cell damage pathways, and cause oxidative stress and inflammation.
In cold conditions where our core temperature is lowered, the heat promoting center initiates actions to conserve the heat that is made and produce more heat when and if it is needed. Again a signal is sent to the muscle fibers around the blood vessels in the skin that constricts and decreases the flow which in turn reduces a large amount of heat loss keeping warm blood deep in the body tissue. If the body requires more heat, the hypothalamus sends a signal to the adrenal glands which will increase burning of carbohydrates to increase heat in the body. This vasoconstriction restricts the amount of blood flow that is reaching the skin, therefore limiting the nutrients being delivered to the skin, and toxins being removed or elimiated. This will often result in a sluggish skin, with a paler or greyish appearance, with slower wound healing and functions.
During consultation, we can look for certain factors that can impact skin temperature to determine if this is impacting the client's skin condition. Common factors include basal metabolic rate, sleep, climate/environment and malnutrition.
Other considerations can include:
Exercise – Strenuous exercise can increase body temperature by up to 15 to 20 times the normal metabolic rate.
Hormones – Thyroid hormones increase the basal metabolic rate by stimulating aerobic cellular respiration. The reason for this is the cells will use more oxygen to produce ATP which will stimulate more heat within the body. Testosterone, insulin and human growth hormone can increase the metabolic rate by up to 10%.
Nervous System - When we become stressed our autonomic nervous system is stimulated. Hormones such as epinephrine and norepinephrine are stimulated and released which increases the metabolic rate of body cells.
Body Temperature – High body temperatures and fever will increase the biochemical reactions by at least 10%.
Food Ingestion – Energy intake increases our metabolic rate by 10-20%. Thermogenesis that is induced by food is highest after eating a high protein meal where it is a lot less after eating carbohydrates.
Age – As we age our metabolic rate slows down to almost half that it was as a child.
My reason for writing this article is to alert the reader to the importance of conducting thorough skin consultations. As I continue my studies of the skin, I become more and more aware of the countless amount of information that we need to gather through our consultation process. It is essential that thoroughly understand conditions that cause skin disorders so that we can successfully determine treatment protocols and prescribe the correct products based on the client’s individual needs.
Yours in skin,
Gay Wardle
References:
Farrell, S., Savelski M. J., Hesketh, R. (2005) Energy Balances of the Human Body
Tortora, G. J. & Derrickson, B. (2009) Principles of Anatomy and Physiology
Richards (2007) Thermal Energy and the Human Body