Glucose is the primary source of energy in the body.
It can be absorbed directly from dietary glucose, or obtained from other sources (eg, splitting complex carbohydrates into individual glucose molecules).
Glucose in the blood doesn't actually provide for any energy needs: The glucose must cross into the cell (an insulin-dependent process) before it can be metabolized. Diabetics, who are insulin-deficient, usually have plenty of glucose, but they can't metabolize it within the cells because they don't have enough insulin.
Glucose levels may rise in the presence of:
Diabetes
Pancreatitis
Acute stress reactions
Pheochromocytoma
Hyperthyroidism
Brain injury
Liver disease
Glucose levels may fall in the presence of:
Excessive insulin administration
Hypothyroidism
Sepsis
Addison's disease
Normal Values*
Fasting
Men
70-110 mg/dl
3.9-6.1 mmol/L
Women
75-115 mg/dl
4.2-6.4 mmol/L
Pregnancy
60-105 mg/dl
3.3-5.8 mmol/L
2-Hour Post-Prandial
Men-Women
<140 mg/dl
<7.8 mmol/L
Pregnancy - Post 50 G Glucose Load
Screening
<135 mg/dl
<7.5 mmol/L
Pregnancy - Post 100 G Glucose Load
Fasting
95 mg/dl
5.3 mmol/L
1-Hour
180 mg/dl
10.0 mmol/L
2-Hour
155 mg/dl
8.6 mmol/L
3-Hour
140 mg/dl
7.8 mmol/L
If two or more of these values are exceeded, gestational diabetes is present.
*These are general values taken from a variety of sources. The actual normal values may vary from lab to lab and from one type of testing protocol to another.
Source: Operational Medicine 2001, Health Care in Military Settings, NAVMED P-5139, May 1, 2001, Bureau of Medicine and Surgery, Department of the Navy, 2300 E Street NW, Washington, D.C., 20372-5300
