Diet has the greatest influence on glucose and triglycerides in biochemical projects, because the intake of any carbohydrate will cause the increase of blood sugar; The intake of oil will affect the determination of triglyceride; Eating a high-protein and high-purine diet the day before blood drawing will lead to an increase in uric acid or urea nitrogen, but it has little effect on creatinine; Caffeine-containing beverages will affect the determination of some drugs and hormones, and will also increase the concentration of plasma free fatty acids.
In addition, after fasting for more than 16 hours, the contents of serum albumin, transferrin, glucose and complement C3 will decrease due to excessive hunger, and serum bilirubin will increase due to the decrease of clearance rate. Drinking alcohol will increase plasma uric acid and lactic acid. A large amount of high-salt diet for a short time will cause a significant increase in electrolyte sodium and chlorine, while long-term non-eating will cause hyponatremia, which will affect the detection indicators.
Recently, it has been found that taking some health care products, such as ganoderma lucidum spore powder and spirulina, will lead to a significant increase in some tumor markers, which is believed to be caused by the cross-reaction between some heterophilic antigens in these health care products and these carbohydrate antigens. Therefore, it is suggested to stop taking the above health care products for one week before detecting tumor markers to avoid getting false positive results.
In addition to the blood test items affected by diet, some urine and feces results will also be affected by diet. For example, drinking a large number of drinks with high sugar content such as cola and sprite can lead to positive urine sugar; After taking a large amount of vitamin C, it will interfere with the examination of urine occult blood, urine sugar and urine bilirubin, resulting in false negative results. Long-term hunger can lead to urine ketone body positive reaction.