Does the physical examination need an empty stomach?

Yes, blood drawing and abdominal ultrasound examination need fasting, otherwise the blood biochemical indexes are somewhat inaccurate, and the gallbladder contraction is unclear during ultrasound.

There are mainly the following reasons:

1. The normal reference values of many blood tests are obtained from the results of fasting blood drawn by normal people.

2. After eating, many chemical components in blood will change, so it is impossible to obtain accurate detection values. After eating the night before, the fasting time reached more than ten hours, and various substances in the body reached a relatively stable balance. Food factors had little effect on blood components. At this time, blood sampling can obtain relatively stable and accurate results.

3. The change of human biological cycle, some indicators change greatly due to different blood collection time, such as cortisol secretion peaks in the morning and gradually decreases from afternoon to evening, so the results measured at the same time are comparable.

4. People exercise less in the morning, and eating will make some laboratory indexes fluctuate, which hinders the accuracy of laboratory results.

Extended data

Precautions for physical examination:

First, please make an appointment for a physical examination; Avoid alcohol the day before physical examination, limit the high-fat and high-protein diet, and avoid using drugs that affect liver and kidney function.

Two, three to five days before the examination, diet should be light, do not eat bloody food such as pig liver, pig blood, check the night before 12, please completely fast (including drinking water).

Third, blood drawing and hepatobiliary ultrasound must be performed on an empty stomach; Do not urinate when doing B-ultrasound of bladder, prostate and appendix; If there is no urine, drink water until the bladder is full.

Four, do X-ray examination, should wear cotton underwear, do not wear clothes with metal buttons, bra; Please take off your necklace, mobile phone, pen, keys and other metal objects. Female candidates who are pregnant or may be pregnant, please inform the health examination service staff first and have a careful X-ray examination.

5. Female physiological period, not suitable for gynecological examination and urine test; Empty the bladder before gynecological examination; It is best to choose breast far-infrared reexamination within one week after the physiological period.

Baidu encyclopedia: physical examination