Does Your Blood Really Thin in Warmer Climates?

Author’s note: This article is summarized from various sources, and attributions are linked within.

person in walking in the snowPhoto byThom HolmesonUnsplash

When I moved from Massachusetts to California nine years ago, I adjusted quickly to the warmer temperatures. Though before, 65 degrees felt like beach weather, once I adjusted I began to feel cold as soon as the temperature dipped below 70. Many people told me that was normal as my blood had thinned. Turns out, that’s not true. Blood doesn’t actually thin. This is a myth that’s been handed down for generations.

Per Reference.com, “Blood viscosity is in no way affected by the heat or cold of the surrounding environment, so blood does not thin in hot weather.” However the body does behave differently according to your environment. Extreme temperatures differ in their impact to a human body.

Homeostasis, a function of our bodies, ensures that our blood and organs remain at a consistent temperature, outside of extreme temperatures. Blood viscosity, how thin your blood is, it one of the factors managed by homeostasis. A consistent temperature is “essential to human health.”

A simple demonstration of how thinning of the blood does not affect body temperature can be evidenced by those taking blood thinners. These medications “have many surgical and medical applications, but they do not make a person feel warmer or cooler because there is no significant linkage between blood viscosity and temperature.”

Circulation is impacted by “internal thermo-regulation, with blood vessels relaxing and contracting in heat and cold respectively. This allows for the dissipation of body heat in the event that external temperatures are high and for the preservation of heat when external temperatures are low, thus preserving the system’s efficiency.”

So why do we feel cold once we get settled in a warmer climate?

One reason could be that as we age, we feel colder.

This feeling is a natural progression of aging, One reason is because our skin becomes thinner. We lose skins cells over time that don’t regenerate, and also fat which serves as insulation. “This fat loss tends to happen more in the legs and arms, making these areas feel colder than the rest of the body.”

Another factor that contributes to feeling colder as we age is the loss of muscle mass. Starting about 30 years old, we c lose “3% to 8% of muscle each decade. By age 65, many individuals have lost 10% or more of their muscle mass, and by age 80, it can be as much as 30%. Muscle tissue is responsible for generating heat, so less muscle means less warmth.”

Though feeling chillier is common in aging, it’s worth mentioning to your doctor as there can be additional causes, especially if it comes on suddenly. “In rare cases, feeling colder can be a symptom of an underlying health condition, such as diabetes, poor circulation, heart failure, hypothyroidism, or anemia.”