Does Weight Loss Prevent Type 2 Diabetes?

Finger-pricking four times a day gets old real quick!

Finger-pricking four times a day gets old real quick!

I found an interesting statistic in a scientific journal article last year:

Every 2.2 pound (1 kg) loss of excess weight lowers the risk of developing type 2 diabetes by 16%.

That tidbit was embedded in another article with a focus on regain of lost weight over time.  The “16% per kilogram” number sounded too good to be true, and I had never heard it before.  So I did some digging and found the source of the statistic.  Ain’t the Internet wunnerful?

The origin of the 16% figure is the Diabetes Prevention Program Research Group.  Investigators enrolled 1,079 middle-aged (mean 50.6 years) study participants and followed them over 3 years, noting the effects of exercise, percentage of fat in the diet, and weight loss on the subsequent development of diabetes.  Average body mass index was 33.9.  (A 5-foor, 4-inch person weighing 197 pounds (89.5 kg) has a BMI of 33.9).  Sixty-eight percent of participants were women.  The investigators’ goal for this group of overweight people was for loss of 7% of body weight through diet, physical activity, and periodic counseling sessions.  Average weight loss over the course of three years was 9 pounds (4.1 kg).

None of the study participants had diabetes at the time of enrollment.  But, by design, they all had laboratory-proven “impaired glucose tolerance.”  Impaired glucose tolerance is a form of “pre-diabetes.”  It is determined by giving a  75-gram dose of glucose by mouth, then measuring blood glucose (sugar) 2 hours later.  A blood glucose level under 140 is normal.  If the level is 140-199, you have impaired glucose tolerance.

Having impaired glucose tolerance means that study participants’ glucose (sugar) metabolism was already abnormal.  They were at higher than average risk of developing diabetes, compared with both average-weight healthy people and overweight people without impaired glucose tolerance.  This is a great cohort to study for development of diabetes.  But the finding that “every 2.2 pounds of weight loss lowers the risk of diabetes by 16%” applies to this particular group with impaired glucose tolerance, not the general overweight population.

A total of 153 participants developed diabetes over the course of 3 years.  Loss of excess weight was by far the best predictor of lowered diabetes risk, compared with regular exercise and lowering percentage of dietary fat.

Yes, weight loss does prevent diabetes in some, probably many, overweight people.  The specific degree of reduced risk depends on numerous factors, such as age, sex, genetics, degree of weight loss, and pre-existing impaired glucose tolerance.

Steve Parker, M.D.

Reference: Hamman, Richard, et al.  Effect of Weight Loss With Lifestyle Intervention on Risk of Diabetes.  Diabetes Care, 29, (2006): 2,102-2,107.

7 Comments

Filed under Overweight and Obesity, Prevention of T2 Diabetes, Weight Loss

7 responses to “Does Weight Loss Prevent Type 2 Diabetes?

  1. joanna

    I am very discouraged. I was diagnosed with type 2 diabetes about a year and a half ago. As if that weren’t enough, I’ve been struggling with chronic fatigue syndrome for 8 years. My grandpa and father both have had type 2 and it turned into type 1.
    I’m 48 and am overweight. My blood sugar is never under 100. I am constantly hungry-thus, it is impossible so far for me to lose weight. I struggle with low blood sugar.
    I keep reading that insulin resistance is reversible with diet and exercise. My struggle is-how to exercise when I’m so tired all the time? And also-how can I lose weight when I am eating all the time?
    Can you help? I often want to just give up. Already some of my toes go numb from time to time. I do take metformin once a day.

  2. Hi, Joanna.

    I’m sorry things aren’t going well for you at this point. But please don’t give up. It can definitely get better.

    NutritionData.com has a good exercise program called “Four Weeks to a Fitter You.” I suggest you check it out. Here’s the URL: http://blog.nutritiondata.com/dieting_weight_loss_blog/spring_shape_up/index.html

    I’m confused about your glucoses. You say your sugar is never under 100 yet you struggle with low blood sugar. Low blood glucoses would be under 65-70 mg/dl.

    Regarding your hunger: Be sure to eat three or four meals daily. Don’t skip meals. Ever try a tsp of sugar-free Metamucil in 8 oz of water once or twice daily?

    Be sure to work closely with your personal physician. And a dietitian may be very helpful.

    The Chronic Fatigue Syndrome is a tough nut to crack. Whoever figures out the cause or cure should win a Nobel Prize in Medicine.

    -Steve

  3. joanna

    I was told by a doctor that low blood sugar can move up-in other words, 170 could be considered low blood sugar for some people.
    Is this true?
    Mine is never under 100 or even near there. Yet, my stomach can feel empty and I can feel dizzy and my head gets fuzzy until I eat something. I don’t know how much my adrenals play into those symptoms because they can make me feel dizzy also.
    I’m just really confused right now.

    • I’ve had a few patients with diabetes that have been so used to living with glucoses of 250-300 mg/dl – for years – that when it gets below 200 they feel strange. With them, we’ve had to work more slowly to reach “normal” glucose levels of 80-160.

      -Steve

  4. joanna

    what should I do to feel better at lower levels?
    I only ever feel “well” when I have a stomach
    full of food. 😦

  5. Beate

    I would love to meet these researchers! I lost 50 (FIFTY!!) pounds on my way from BMI 34 to 24. I have just been diagnosed with ‘severe’ diabetes (endo’s words not mine). The last 10 pounds of the weight loss was probably due to undiagnosed diabetes, but I did ‘pass’ an oral glucose tolerance test about the same time I hit the 40 pounds mark. I don’t have any relevant antibodies and I’m severely insulin resistant.