What is Flexible Insulin Therapy?
(Intensive Management)
Flexible Insulin Therapy (FIT) is a different way of thinking about your diabetes care. FIT allows you to adjust the timing and amount of insulin to meet your needs. For example, you may correct your meal-time bolus insulin doses up or down to reflect such things as
  • your current blood glucose level
  • the carbohydrates you plan to eat
  • the exercise that you plan to do

Flexible insulin therapy is possible because today's rapid-acting insulins are injected at the exact time you eat, not 30 minutes before. Since you inject right at mealtime, you can make spontaneous food choices at a meal, then adjust the insulin dose to reflect the grams of carb that you actually eat. Some people use the names 'Flexible Insulin Therapy' and 'Intensive Insulin Therapy' to mean the same thing.

A Proven Approach
Testing and Injecting Often Reduces Diabetes Complications

Research shows that frequent testing and injecting really works. From 1983 to 1993, a group of people with type 1 diabetes participated in a large U.S. clinical study called the Diabetes Control and Complications Trial (DCCT). They tested their blood glucose four or more times a day. They injected insulin three or more times a day. Some of the participants adjusted their insulin doses based on their blood glucose, food intake, and exercise.

  • After nine years, the frequent testers/injectors were compared to a control group that consisted of people with type 1 diabetes who injected insulin and tested their blood glucose one or two times a day. The people who tested and injected more often had fewer diabetes complications:
    • They reduced the risk of developing eye complications by 76%. People who already had some eye disease reduced the risk of future worsening by 54%.
    • They reduced the risk of early kidney disease by 43%. The risk of later kidney disease was lowered by 56%.
    • They experienced a reduction of more than 60% for the risk of confirmed nerve damage.
    • Lastly, their risk for high cholesterol was lowered by 40%.
  • On the other hand, the EDIC study, which continued to follow the DCCT participants, showed that a person's poor blood glucose control in early years can have effects that last up to ten years, even if the person switches to a more intensive insulin therapy.

Flexible Insulin Therapy Improves Quality of Life [2]
Research also shows that flexible insulin therapy improves people's quality of life. A one-year clinical study in Great Britain called DAFNE (Dose Adjustment for Normal Eating) was conducted in 2001-2002. 136 adults with type 1 diabetes were taught how to count carbs and adjust their mealtime insulin based on the carb grams. Compared to a control group, after 12 months of flexible insulin therapy:

  • DAFNE patients had significantly better HbA1c levels.
  • They reported greater feelings of well-being and higher satisfaction with their treatment, in spite of the fact that they were testing and injecting more often.
  • Cardiovascular risk factors and episodes of low blood glucose did not change significantly in either the test and control groups.

Is Flexible Therapy Right For You?
Because of the positive findings of the DCCT study, healthcare professionals recommend that many people with type 1 diabetes test and inject at least three times a day - preferably more. Some people with type 2 diabetes may also do better if they test and inject more often.

Going one step further, the DAFNE study suggests that people who test and inject often will be more satisfied with their diabetes care if they follow flexible insulin dosing. Could the extra steps of flexible therapy work for you? Answer these questions to find out:

  • Are you enthusiastic and motivated to keep your blood glucose in target?
  • Are you willing to make an extra effort to avoid the health complications of diabetes?
  • Are you willing to calculate insulin dose corrections based on the amount of carbohydrates that you eat?
  • Are you willing to check your blood glucose at least four times a day?
  • Can you inject insulin at least three times a day?
  • Can you fill out a daily blood glucose and insulin diary?

If you answered, "Yes" to most of these questions, ask your doctor about FIT. To see if you are able to handle the extra work, your doctor may ask you to do four blood glucose tests a day for a month, and to keep a diary of your test results and insulin doses. There is a greater risk of hypoglycemia with FIT, so it's not for everyone. It should be used cautiously with children under the age of 13 years, and for people who have:

  • Recurrent hypoglycemia (low blood glucose).
  • Hypoglycemia Unawareness (in which one does not experience the symptoms of low blood glucose)
  • Advanced kidney disease, eye disease, or nerve disease
  • A prior history of heart disease or stroke 


  1. Sustained Effect of Intensive Treatment of Type 1 Diabetes Mellitus on Development and Progression of Diabetic Nephropathy The Epidemiology of Diabetes Interventions and Complications (EDIC) Study
    Writing Team for the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications Research Group
    JAMA. 2003;290:2159-2167.
  2. Training in flexible, intensive insulin management to enable dietary freedom in people with type 1 diabetes: dose adjustment for normal eating (DAFNE) randomized clinical trial. BMJ.2002 October 5; 325 (7367): 746Author (Verdana, -2]