0 Low Glycemic Index Diet Vs High Cereal Fiber Diet

Which of these two diets - a low-glycemic-index (LGI) diet or a high-cereal-fiber (HCF) diet - do you think would produce the better blood sugar control?

Researchers from Toronto set out to answer that question. Their results were published in the December 17 issue of the Journal of the American Medical Association:

Effect of a Low-Glycemic Index or a High-Cereal Fiber Diet on Type 2 Diabetes

Ill give you the answer up front: The low-glycemic-index diet was better, but only moderately.

The 210 participants with type 2 diabetes followed their respective diets for 6 months, at the end of which:

For those who followed the LGI diet:

• HbA1c went down by 0.50 (from 7.14 to 6.64)
  
• HDL went up by 1.7 mg/dl

For those who followed the HCF diet:

• HbA1c went down by 0.18 (from 7.07 to 6.89)
  
• HDL went down by 0.2 mg/dl (HDL is the good cholesterol, you want this to go up)

How Did The Diets Differ?

Low-Glycemic-Index Diet

"The following foods were emphasized: low-glycemic index breads (including pumpernickel, rye pita, and quinoa and flaxseed) and breakfast cereals (including Red River Cereal [hot cereal made of bulgur and flax], large flake oatmeal, oat bran, and Bran Buds [ready-to-eat cereal made of wheat bran and psyllium fiber]), pasta, parboiled rice, beans, peas, lentils, and nuts."

Fruit in the LGI diet leaned toward temperate: apples, pears, oranges, peaches, cherries, and berries.

High-Cereal-Fiber Diet

"Participants were advised to take the "brown" option (whole grain breads; whole grain breakfast cereals; brown rice; potatoes with skins; and whole wheat bread, crackers, and breakfast cereals)."

Fruit in the HCF diet leaned toward tropical: bananas, mangos, guavas, grapes, raisins, watermelon, and cantaloupe

Both Diets

Everyone was advised "to avoid foods such as pancakes, muffins, donuts, white buns, bagels, rolls, cookies, cakes, popcorn, French fries, and chips."
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0 Glycemic Variability

How much do your blood sugars vary in a day?

The answer to this question might have more of a bearing on your risk for complications than your HbA1c alone. Dr. Irl Hirsh (shown) reviewed data on fluctuations in blood glucose. In his 2005 paper he reported: ¹

"New data, however, show that glucose variability, independent of A1C, may also play a significant role in the risk for complications."

He cited an example from the landmark 1993 Diabetes Complications and Control Trial:

"For example, the risk of retinopathy in control patients with an A1C of 9% was approximately 2.5 times greater than the risk of experimental patients with a 9% A1C. The only significant difference between these groups is that 90% of the control group was on twice-daily NPH insulin to cover basal and prandial insulin needs, whereas subjects in the experimental group were on basal-bolus therapy using either NPH insulin twice daily and regular insulin at meals, multiple daily injections, or an insulin pump."

Dr. Hirsch suggested that blood sugars not deviate by more than a third of average blood sugar. If your average BG was 120 mg/dl, you would not want it to fluctuate by more than 40 mg/dl, e.g. you would not want it to go higher than 160 mg/dl.

A goal for therapy that addresses both chronic high blood sugars (hyperglycemia) and glycemic variability was discussed in a recent article in the journal Diabetes Care (February Supplement): ²

"It is strongly suggested that a global antidiabetic strategy should be aimed at reducing to a minimum the different components of dysglycemia (i.e., A1C, fasting and postprandial glucose, as well as glucose variability). All the therapeutic agents that act on postprandial glucose excursions seem of particular interest for reducing the latter parameter (i.e., the glucose instability)."

Managing glycemic variability cannot be adequately accomplished without knowledge of blood sugar variations - which makes regular blood sugar monitoring essential:

"In patients with type 2 diabetes, SMBG* should be performed with increased frequency to monitor glycemic variability, regardless of the effect on HbA1c."
- Glycemic Variability: A Hemoglobin A1c–Independent Risk Factor for Diabetic Complications, Brownlee M and Hirsch I, JAMA, 2006.

* Self-Monitored Blood Glucose

The above makes a good argument for increased use of continuous monitors.
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¹ Glycemic Variability: Its Not Just About A1C Anymore! , Diabetes Technology and Therapeutics, 2005.
² Glycemic Variability, Should We And Can We Prevent It? , Diabetes Care, 2008.

0 Dos of Following a Glycemic Index Diet

* Do choose whole grains over processed whenever you can.
* Do enjoy as many fresh fruits and vegetables as you possibly can every day.
* Do look at the “whole picture” when choosing your food items.

Consider all of its characteristics.
* Do try to have at least one food from the low Glycemic Index list at

every meal.
* Do add vinegar or a no-fat vinaigrette dressing to your food

whenever possible since vinegar is acidic and lowers the food’s

Glycemic Index rating (because it slows down your digestion.)
* Do try as many foods as you can from the low Glycemic Index list.

You may be surprised to find some delicious choices that you have

never tried before.
* Do choose foods that are high in fiber. The higher the fiber the

longer it takes to digest, which will leave you feeling fuller longer

and keep your blood sugars at a steady level
for hours. Aim for between 26-35 grams of fiber per day!
* Do start the day with a great breakfast of low Glycemic Index foods.
* Do try to eat your meals at regular times and on a regular basis.
* Do be aware of the types of fats that you choose. While fat is a

necessary nutrient, some are better choices than others are.

Try to use fats that are better for your heart like olive oil and canola.
* Do eat a variety of good foods every day. Our bodies adjust to foods

and by eating differently all of the time it keeps our system “on its toes”

and in shape.
* Do look for “coarseness” in your food choices. Food that

hasn’t been over-processed will appear to have more texture and

will result in lower Glycemic Index numbers.
* Do plan your menus, shop with a list and buy plenty of fresh fruits

and vegetables when they are in season.
* Do invest in a large variety of herbs and seasonings and

experiment with them to add new and exciting flavors to your meals.
* Do look up new Glycemic Index recipes to try in order to keep

your meals interesting and fun.