Low body temperature (usually under 35–36 °C / 95–96.8 °F) is most often caused by being in a cold environment, but illnesses, hormones, medications, and age can also play a role. When it is significant or persistent, it can be a medical emergency and needs prompt professional evaluation.

What “low body temperature” means

  • Normal oral body temperature in adults is roughly 36.5–37.5 °C (97.7–99.5 °F); values clearly below this, especially under 35 °C, are considered hypothermia.
  • Even a mild drop can make someone feel sluggish, confused, or unusually cold, so symptoms matter as much as the number.

Big-picture causes

Low body temperature generally comes from one or more of these mechanisms:

  • Increased heat loss (for example, cold exposure, wet clothes, wind).
  • Decreased heat production (for example, low thyroid, malnutrition, severe infection, very low blood sugar).
  • Problems with the body’s thermostat in the brain or nervous system, or from certain drugs that blunt the temperature response.

Common everyday triggers

  • Staying outside in cold weather without enough warm, dry layers, especially with wind (“wind chill”) or rain/snow.
  • Falling into cold water, or wearing wet clothing for a long time in the cold.
  • Being exhausted, dehydrated, or not eating enough while in the cold so the body cannot keep generating heat.

Medical conditions that can cause it

  • Hormone and metabolism problems
    • Hypothyroidism (underactive thyroid) slows metabolism and can lower body temperature.
* Low blood sugar and malnutrition reduce available energy for heat production.
  • Serious infections and illness
    • Sepsis and severe illness in older or very sick people can present with low, not high, temperature.
* Major burns or skin conditions can increase heat loss through damaged skin.
  • Brain and nerve conditions
    • Stroke, head injury, neurodegenerative diseases, or spinal cord injury can disrupt the hypothalamus (the body’s “thermostat”).

Medications, substances, and age

  • Medications and substances
    • Sedatives, some anti-anxiety drugs, antipsychotics, general anesthetics, beta‑blockers, and overuse of fever‑reducers can all contribute to a lower body temperature.
* Alcohol and some recreational drugs impair judgment, cause blood vessels to widen at the skin, and increase heat loss.
  • Age-related factors
    • Newborns and older adults lose heat faster and may not shiver or “feel” cold normally, making low body temperature more likely and more dangerous.

When to worry and what to do

Seek urgent medical help (emergency services) if:

  • Body temperature is around or below 35 °C (95 °F), or a person is confused, very drowsy, having trouble speaking, or shivering uncontrollably.
  • There is suspected sepsis, overdose, head injury, or prolonged exposure to cold or cold water.

For milder situations in an otherwise healthy person:

  • Get out of the cold, remove wet clothing, and warm the core (chest, abdomen) with blankets and warm (not hot) drinks if the person is alert.
  • If low temperatures keep happening, or you feel unusually cold with fatigue, weight change, or hair/skin changes, a check for thyroid, infection, anemia, or other medical issues is important.

Information gathered from public forums or data available on the internet and portrayed here.