Glucose is a type of sugar from food that the body uses for energy. The level of glucose in the bloodstream usually rises after a meal. To be efficiently utilized by the body, glucose in the bloodstream needs to enter the body’s cells. If glucose is unable to enter the cells, blood glucose levels rise leading to hyperglycemia. Long-term hyperglycemia damages nerves, blood vessels and vital organs.
Insulin is a hormone produced by the beta cells of the pancreas. The beta cells release more insulin whenever there is a rise in blood glucose levels. Insulin enables glucose to enter the cells, thereby restoring normal blood glucose levels and allowing efficient glucose metabolism.
People with type 1 diabetes can no longer produce insulin because the disease has destroyed the beta cells of their pancreas. People with type 2 diabetes can produce insulin but their body does not respond well to it, a condition known as insulin resistance. Insulin resistance also develops in pregnant women with gestational diabetes because the placenta (organ that connects the fetus to the mother’s blood supply) produces insulin-blocking hormones.
Insulin therapy replaces or supplements the body’s own insulin, thereby restoring normal or near-normal blood sugar levels. It is one of the cornerstones of diabetes management, providing intensive blood glucose control crucial in preventing diabetes-related complications. Why is insulin injected into the fat under the skin rather than taken as a pill? Because insulin taken in pill form would be broken down by digestive enzymes and rendered ineffective.
The first generation of man-made insulin is called “human insulin.” Developed through the 1960s and 1970s and approved for pharmaceutical use in 1982, human insulin is the name given to synthetic insulin “grown” in the laboratory to mimic the insulin produced by the human pancreas. Before human insulin was developed, animal insulin—usually a purified form of porcine (pig) insulin—was used for insulin therapy. Human insulin is available in three types: regular (short-acting), intermediate-acting (also called NPH) and premixed. Premixed human insulin is a mix of regular and NPH insulin.
In the late 1990s, a new type of synthetic insulin was developed. Analog insulin is also laboratory-grown but genetically altered to produce either more rapid or more uniform effect on blood glucose levels. As such, analog insulins can provide advantages for blood glucose management. Analog insulin is likewise available in three types: long-acting, rapid-acting and premixed. Premixed analog insulin is a mix of long- and rapid-acting analog insulin.
Analog insulins are associated with lower risk of hypoglycemia (abnormally low-blood glucose level), lower levels of postprandial glucose excursions (change in blood glucose levels from before to after a meal), better patient adherence, greater quality of life and higher satisfaction with treatment.
While these various types of insulin work differently to mimic the way the body normally releases insulin, they all help to keep diabetes under control. No one type of insulin is right for everyone. Each person’s insulin need is different and may change over time. Your doctor will prescribe the insulin that is best for you.
CONTEST: Insulin can either be injected or taken orally. True or False? E-mail your answer to email@example.com and get the chance to win a prize! Congratulations to Alele Lagaña! Your correct answer to the question in the June 15 column was chosen as this week’s winner in the Diabetes Trivia Contest. You will receive an e-mail on how to claim your prize.
(Dr. Leorino M. Sobrepeña is a diabetes specialist. The “Changing Diabetes” column commemorates the 92nd anniversary of insulin’s discovery. It aims to increase awareness on diabetes prevention, diagnosis and management. Novo Nordisk supports “Changing Diabetes.” Headquartered in Denmark, Novo Nordisk is a global healthcare company with 90 years of innovation and leadership in diabetes care. For questions or comments, e-mail firstname.lastname@example.org or follow us at www.facebook.com/ChangingDiabetesPH.