July 11, 2024
Body Temperature Monitoring: Tools, Tips, and Reasons for Doing It
Maintaining an optimal body temperature is essential to life. Deviation from the normal body temperature range is an important indicator of potential trouble: infection, inflammation, heat stroke, drug reaction, tumor growth or another altered physiological state. Body temperature is one of the seven universally accepted vital signs, along with pulse & respiration rates, blood pressure, body weight, and blood glucose.
Recent studies show that the normal human body temperature is changing and that the “norm” can vary from person to person. Thus, keeping a personal temperature diary and establishing individualized benchmarks can be instrumental in detecting unwanted changes early, taking timely action, and building better health management plans.
What Are Thermoregulation, Homeostasis, Hypothermia, and Hyperthermia?
Thousands of chemical reactions that continuously occur in the human body require temperature to be maintained in a rather narrow range. In fact, our bodies normally regulate temperature more tightly than even our blood pressure or heart rate. The system for thermoregulation (or body temperature control) is very complex and involves many feedback loops with nearly every part of the autonomic nervous system. Thermoregulation is part of homeostasis - the process by which living organisms maintain a stable internal environment despite changes in external conditions.
Thermoregulation in young children is not yet fully developed, making them more susceptible to passive intraoperative hyperthermia (excessive heating) and neonatal hypothermia (defined by the WHO as an axillary temperature below 36.5°C). Hypothermia (body temperature below the norm) and hyperthermia (body temperature above the norm or “fever”) may cause permanent organ damage and even death in people of all ages. Both often require intervention and are cautiously watched against in intensive care units. Normally, the human body employs such thermoregulation mechanisms as sweating, shivering, and blood flow adjustments with the aim of keeping its temperature at around 37°C or 98.6°F, but recent research suggests that these numbers are changing.
Is “Normal” Body Temperature Changing and Is It “Personal”?
In a Harvard Medical School blog post titled “Time to Redefine Normal Body Temperature?”, a senior faculty editor Robert H. Shmerling, MD, shares that “normal body temperature may be falling over time, according to data samples reaching back almost 160 years”. Humans seem to be getting cooler, and the two main reasons responsible for this change are thought to be the lowering rates of infection/inflammation along with lower metabolic rates.
An article by Nina Bai published in Stanford Medicine states that “A new, large-scale study of body temperatures has found that “normal” isn’t one size fits all — it varies by age, sex, weight, size, time of day and more”. Type 2 diabetes has recently been linked to lower body temperatures, moreover, a publication from the Yale School of Medicine titled “Insulin Stimulates Production of Body Heat, New Study Finds” discusses research on how insulin may activate genes that regulate body temperature.
Body temperature IS a marker for metabolic rate. Our personal temperature norm, our spikes and lows are influenced by many factors, potentially changing what mark should be considered as fever. A normal temperature in one person may be abnormal in another, and clinical teams may find it necessary to monitor a patient’s temperature for a while in order to establish their personal baseline.
Why Keep a Temperature Diary?
Keeping a body temperature diary can be a valuable tool for managing health, diagnosing conditions, tracking treatment reactions, and understanding how various factors affect our bodies. A personal temperature log can help recognize patterns, identify trends, establish a personal temperature baseline, collect self-reported data sets to share with a doctor, and increase overall personal health and wellness awareness.
General health, fitness and wellness body temperature monitoring is popular with people who want to understand how their body responds to exercise, detect overheating or potential signs of heat exhaustion. Tracking temperature can reveal patterns related to sleep quality and collect more information for treating such disorders as insomnia.
Basal body temperature monitoring (BBT monitoring) for menstrual cycle tracking can help predict the time of ovulation in women. It is often referred to as “the temperature method” for estimating the time of ovulation (the release of an egg from an ovary) with the aim of identifying the optimal days for becoming pregnant. Menopause or other hormonal changes can cause temperature fluctuations, and tracking these can help manage symptoms.
Medical body temperature monitoring may be recommended for people with such chronic conditions as Diabetes (for managing potential complications) and Thyroid Disorders (both hyperthyroidism and hypothyroidism can affect body temperature regulation).
Fever management may be required for people suffering from infections (tracking fever patterns can help identify trends and effectiveness of treatments), and for post-surgery patients (monitoring for signs of complications). Autoimmune conditions such as lupus or rheumatoid arthritis can cause periodic fevers, and tracking these can help manage and understand individual flare-ups.
Body temperature monitoring is recommended for individuals with compromised immune systems. Patients receiving cancer treatments and other people who have fewer white blood cells (or neutropenia) have a higher risk of infections, and monitoring their body temperature serves as a standard-of-care method in inpatient settings. In fact, studies show that wearable temperature sensors provide early warning for complications in patients undergoing chemotherapy.
Patients undergoing general or neuraxial anesthesia must have their body temperature monitored, since their thermoregulatory control becomes impaired and unable to trigger the normal defense responses.
Workplace temperature testing can provide early warnings of fever and infection, which is especially useful during COVID-19 and other epidemic threats. Employers, public services, airports, educational institutions, and other organizations may use population temperature screening in public spaces for disease control.
Post medication and vaccination changes in body temperature can help catch unwanted side effects, adjust dosages, and take steps to provide additional comfort to patients. Clinical trial participants are also often asked to keep detailed records of their body temperature for research purposes.
What is Important in Maintaining a Temperature Diary?
- Consistency: measurements should be made at the same times each day.
- Details: time, context (e.g., resting, post-exercise), and any relevant symptoms or activities should be noted.
- Tools: only reliable thermometers with all required regulatory clearance should be used, as well as quality apps, specifically designed for tracking health data. For example, MedM’s Health Diary app is one of the best health monitoring apps on the market.
Body Temperature Logs and Sheets
People once relied on paper body temperature monitoring sheets or paper temperature logs, but now smarter alternatives, like diary apps, are available. These digital temp trackers not only simplify recording and safeguarding temperature history, but also offer reminders for scheduled measurements, easy data sharing with caregivers, and alerts when temperature thresholds are exceeded.
What Types of Body Temperature Thermometers are There?
Measuring a person’s body temperature is not possible with the help of a smartphone alone and should involve a thermometer approved for this specific task. Ideally, the process should be simple, fast, non-invasive, reproducible, and cost-effective. So what tools are available? Aside from old-school mercury and alcohol thermometers there are also disposable thermometers, but let us look at the more user-friendly and modern options.
Digital Thermometers
Can be oral (including pacifier thermometers for babies), rectal, or axillary (used in the armpit), these require direct contact and longer measurement times.
Infrared Thermometers
Can be ear (tympanic) or forehead (temporal), are non-invasive and non-contact, respectively.
Wearable Thermometers
Come in the form of patches, armbands, rings, earplugs, and smartwatches, enabling users to receive string temperature readings for continuous body temperature monitoring.
MedM Health Diary app is the world’s most connected personal health monitoring diary in the world, which enables users to log their vital signs and a dozen more biomarkers by automatically capturing measurements from over 800 supported smart health meters, including over 70 connected infrared and digital thermometers that come in an array of formfactors.
