1.Normal Heart Rate: 75 beats per minute (bpm)
In a healthy adult at rest, the average heart rate is 75 bpm.
The normal range is 60-100 bpm. A heart rate exceeding 100 bpm in an adult at rest is tachycardia; below 60 bpm is bradycardia. Heart rate can vary based on age, gender, and other factors, such as increasing by 12-20 bpm for each 1°C rise in body temperature. Female heart rates are slightly faster than males, and athletes typically have slower heart rates.
2.Normal Body Temperature: 36.3°C-37.2°C(Oral Method)
Clinically, body temperature is represented by oral, rectal, and axillary measurements. The normal range for the oral method (held under the tongue for 5 minutes) is 36.3°C-37.2°C; for the axillary method (held under the armpit for 5 minutes), it is 36°C-37and for the rectal method (inserted into the rectum for 5 minutes with lubricant), it is 36.5°C-37.7°C. Body temperature fluctuates cyclically throughout the day, usually lowest between 2-6 AM and highest between 1-6 PM, but the fluctuation generally does not exceed 1°C. A temperature below 37.3°C is considered normal.
3.Hemoglobin (HbB): 120-160 g/L for adult males, 110-150 g/L for adult females
Hemoglobin levels are used clinically to assess anemia. Normal adults with hemoglobin levels of 90-110 g/L have mild anemia; 60-90 g/L, moderate anemia; and 30-60 g/L, severe anemia.
4.White Blood Cell Count (WBC): 4-10 x 10^9/L
A WBC count above 10 x 10^9/L is called leukocytosis, and below this range is leukopenia. Generally, acute bacterial infections or inflammation can increase WBC counts; viral infections can decrease them. Colds and fever can be caused by either viral or bacterial infections. To determine the cause and guide treatment, doctors may order a complete blood count (CBC).
5.Platelet Count (PLT): 100-300 x 10^9/L
Platelets maintain the integrity of blood vessels. When platelet counts drop below 50 x 109/L, bleeding may occur, with skin manifestations like petechiae and ecchymoses. However, individuals with normal platelet counts who frequently experience bruises should not panic as factors such as vascular wall issues, coagulation factors, and physiological factors can also cause bruises. Consulting a hematologist for diagnosis is recommended.
6.Urine Output: 1000-2000 mL/24 hours
Urine output exceeding 2500 mL/24 hours is considered polyuria, which can be physiological (due to excessive water intake or diuretic use) or pathological (e.g., diabetes, diabetes insipidus, renal tubular diseases).
Urine output below 400 mL/24 hours is oliguria, commonly seen in dehydration, insufficient water intake, and renal insufficiency.
Less than 100 mL/24 hours is anuria, indicating severe conditions like renal failure or shock.
Reminder: If you notice increased urine output and excessive thirst, consult your doctor to rule out diabetes or renal tubular diseases. If you drink adequately but have decreased urine output accompanied by swelling, prompt medical attention is needed to exclude renal issues.
7.Nocturnal Urine Output: 500 mL
Nocturnal urine refers to the total urine output from 8 PM to 8 AM the next day, typically 500 mL with 2-3 voidings. Increased nocturnal urine output with more frequent urination than during the day is termed nocturia. Physiological nocturia is related to excessive fluid intake before sleep; pathological nocturia often indicates impaired renal concentrating ability, an early sign of renal dysfunction.
Reminder: Nocturia is an abnormal sign. Besides renal dysfunction, it can also be caused by male prostate enlargement, uterine prolapse in elderly women, urinary tract infections, diabetes, and stress.
8.Urine Red Blood Cell Count (RBC): Normal Value: 0-3/high-power field (HPF)
3 RBCs/HPF is called microscopic hematuria;
>10 RBCs/HPF, gross hematuria.
Reminder: An RBC count exceeding 3/HPF often suggests renal pathology or urinary tract infection, requiring immediate medical attention. Female patients should avoid urine tests during menstruation to prevent contamination and false results.
9.Urine White Blood Cell Count (WBC): Normal Value: <5/HPF
A urine WBC count >5/HPF is termed microscopic pyuria.
Reminder: A high urine WBC count, especially if above the normal range, suggests urinary tract infections such as pyelonephritis, renal tuberculosis, cystitis, or urethral infections. Counts below 5/HPF are considered normal.
10.Survival Time: 72 hours for spermatozoa, 24 hours for ova
Reminder: Many couples use the rhythm method for contraception, but unfortunately, it’s not always reliable. Besides miscalculating the fertile window, another factor is that spermatozoa can survive up to 3 days in the female body. Therefore, even if it’s not the ovulation day, fertilization is still possible during the fertile period (4 days before to 2 days after ovulation).
11.Two Major Blood Type Systems: ABO and Rh
The ABO system categorizes blood into four types: A, B, AB, and O.
The Rh system divides blood into Rh-positive and Rh-negative.
Among Caucasians, 85% are Rh-positive and 15% Rh-negative.
Reminder: If the father is type A and the mother is type B, the possible blood types for the child are A, B, AB, or O. Don’t be surprised if both parents are not type O but the child is.
However, if one parent is AB, the child cannot be O; if both parents are O, the child must be O.
12.Body Mass Index (BMI) = Weight (kg) / Height² (m²): 18.5-23.9 is normal
BMI <18.5 indicates underweight;
24.0-27.9, overweight;
≥28.0, obesity.
Reminder: If your BMI exceeds 24, you are overweight and should consider weight loss. Remember, obesity is a root cause of many diseases, including diabetes, hypertension, and coronary heart disease.
13.Optimal Weight Loss Rate: 1-2 kg per month
Reminder: Overweight individuals should lose weight gradually under medical guidance. Rapid weight loss can lead to rebound weight gain, anorexia, anemia, malnutrition, menstrual irregularities, hair loss, memory decline, osteoporosis, and other adverse effects.
14.Waist Circumference: 90 cm for males, 80 cm for females
Exceeding these values indicates abdominal obesity, a risk factor for coronary heart disease and metabolic syndrome.
Reminder: If your BMI is within the normal range but your waist circumference exceeds the threshold, you have abdominal obesity, which is more dangerous than generalized obesity and increases the risk of coronary heart disease and diabetes. Be cautious!
