Using Glycemic Index/Glycemic Load to Control Blood Glucose

The primary reason for my change to a lower-carbohydrate diet is to control my blood glucose (BG) and improve my insulin sensitivity, a choice resulting from my recent discovery that my sugars have been silently creeping up over the years. I know I'm succeeding when the number on my BG meter is in the low 100s after a meal.

I'm not pursuing low-carb as a means to lose weight (although, given my experience, if it's weight loss you're after, you'd be throwing away a chance for success if you don't try this), manage my cholesterol (although, low-carb has been shown to increase HDL and lower triglycerides), or pay homage to a Paleolithic diet (thus, I continue to eat the dark meat on poultry, fatty cuts of meat, cheeses, green beans, peas, peanuts and peanut oil, lentils, soy nuts, corn-on-the-cob, pickles, vinegars, and other foods deemed unacceptable on the Paleo Diet).

How do I determine what to eat?

1. The total carbohydrate in a serving of food (quantity).
   
2. The tendency of that carbohydrate to raise my blood glucose, as measured by its glycemic index (GI) (quality).

Fats have very little effect on blood glucose. Proteins have a small effect. Carbohydrates have quite an impact.

There are many types of carbohydrates. Sugars are short-chain or no-chain carbs. Starches are mid-to-long-chain carbs. Those long chains may be either straight (amylose), or branched (amylopectin). Some carbs, such as cellulose, are not digestible by human enzymes and thus are one constituent of "dietary fiber". These and other factors influence how fast a carbohydrate will raise blood sugar. Low GI foods do not raise blood sugar as fast or as high as higher GI foods.

When you combine the effect of items 1 and 2 (quantity and quality) above, you define the glycemic load (GL) of a serving of food.

GL = Carbohydrate (g) x GI / 100
That is, the glycemic load of a serving of food is equal to the total carbohydrate in that food multiplied by the food's GI. If you consider the GI as a percentage then the above result would be divided by 100.

A GL of less than 10 is considered low. A GL of greater than 20 is considered high.

For example:

• The GI of Ocean Spray Cranberry Juice Cocktail is about 68.¹ One half cup has 18g carbohydrate. So, the GL of that 1/2 cup of juice is around 12:
  GL = 68 x 18 / 100 = 12.24
  
  
• The GI of Silk Soymilk, Plain is 18. One cup has 8g of carbohydrate. So, the GL of that 1 cup of soymilk is around 1 or 2:
  GL = 18 x 8 / 100 = 1.44
  
  
• The GI of a medium-sized (7" to 8"), yellow banana is about 51. One banana has about 27g carbohydrate. So, the GL of a banana is around 14.
  GL = 51 x 27 / 100 = 13.77
  
  
• The GI of cooked, medium-grain brown rice is about 50. One cup has about 46g carbohydrate. So, the GL of 1 cup of brown rice is around 23.
  GL = 50 x 46 / 100 = 23
  
  
• The GI of a cooked Russet potato is about 85. One potato (3 to 4.25 in) has about 64g carbohydrate. So, the GL of 1 potato is around 54.
  GL = 85 x 64 / 100 = 54.4

If looking things up in tables or doing math has a similar appeal to you as cleaning bathrooms, you'll be happy to know there are sites like NutritionData.com that will do it for you.

________
Glycemic Load In Action

Below is a comparison of the glycemic load provided by two breakfasts. I chose RB's and mine from yesterday as an example. (See comments under Global Prevalence of Diabetes.) Data on GL was derived from NutritionData.com.

RB's Breakfast:

1 cup Cheerios, GL = 13
1 tablespoon (0.5 oz.) raisins, GL = 7
1/2 cup 2% milk, GL = 5
1 cup orange juice, GL = 9
Total GL for meal = 34

Bix's Breakfast:

1/4 cup almond/pecan/pistachio/pumpkin seed mix, GL = 2
1/4 cup spaghetti squash, GL = 1
1/4 cup tomato sauce, GL = 2
2 teaspoons grated cheese, GL = 0
1/4 cup blueberries, GL = 2
Total GL for meal = 7
(One large egg's GL = 0. I could have added an egg omelette to the above and still clocked in with a total GL of 7.)

I'm finding when a meal contains a glycemic load of 15-20 or above, my blood sugars stay high for a while. RB's breakfast, which was not so different from how I ate before my recent finding, would cause my blood glucose to rise and stay elevated for hours. Likely, I would also have undesirably higher levels of blood insulin, secreted by my pancreas to compensate for the ineffectiveness of smaller amounts of insulin - amounts which may have sufficed if my cells were less insulin resistant.

From the information above, you can see why I've chosen to severely limit my consumption of whole grains, potatoes, and other starchy foods. I haven't yet signed onto the idea of cutting out entire food groups (e.g. grains), especially when I consider we have a whole planet to feed. But, for me, just 1/2 baked potato, 1/2 cup brown rice, or 1 cup whole-wheat pasta is enough to keep my BG elevated. A Starbucks cinnamon raisin bagel has a glycemic load of 62! I may as well inject glucose directly into my bloodstream.

In answer to Autumn's question from yesterday:

"... what about brown rice and quinoa and whole wheat? What happens to blood sugar if one consumes only whole grains?"

Blood sugar responses are unique to an individual. However, those who have insulin resistance, prediabetes, or have been diagnosed with diabetes would do well to control intake of starchy and grain-based foods, whole grain or not, given their higher glycemic load. Those who do not have those conditions may wish to consider that the long-term consumption of a diet with a relatively high GL was found to be associated with an increased risk of type 2 diabetes and coronary heart disease.
________¹ A very thorough and comprehensive table of GIs can be found at the International Table Of Glycemic Index And Glycemic Load Values: 2002. You may also check a food's website for this info.
² Silk Soymilk website.

Photo: Homegrown (Cheerios).

Global Prevalence of Diabetes

Melinda raised an interesting point:

"I wonder if the billions of Indian, Chinese, Tibetan, etc. vegetarians or vegans (many for religious reasons) are diabetic and obese b/c of their diet. Damn few, I bet."

That made me wonder. Do the Indians and Chinese fare better when it comes to diabetes? It would be telling if they did.

A recent source for the global prevalence of diabetes is the work of Wild et al., that appeared in the journal Diabetes Care in 2004:

Global Prevalence of Diabetes: Estimates for the year 2000 and projections for 2030

At right is a table from the study, "List of countries with the highest numbers of estimated cases of diabetes for 2000 and 2030". It's informative, for the sheer number of people in the world afflicted. But this table provides pure numbers (not percentages) which could appear to over-represent the disease in highly-populated countries like India and China. It's also fair to say that estimates for the number of people with diabetes in developing countries are more difficult to come by, and may therefore, conversely, be under-representative.

Diabetes In India

I decided to focus on one country, India. According to David Mendosa, one of the biggest and best sites devoted to diabetes in India is run by the husband and wife team, Dr. Rao and Dr. Ushabala: Diabetes-India.com

They state:

"Prevalence of diabetes in urban India is 10 per cent." [It's about 7% here in the US.] In a more recent interview by Mendosa, Dr. Rao revealed, "But we have small studies this year [2001] that say that 14 percent of the population of our cities has diabetes."

"Indians tend to be diabetic at a relatively young age of 45 years which is about 10 years earlier than in West."

"The life expectancy in a diabetic is just about 8 years after the onset of the disease, as they succumb to kidney as well as heart disease more often than others."

"Indians eat less, weigh less and work more than Europeans." ... yet they are "more prone for diabetes than Europeans."

I don't know how meat consumption compares in the US and India. I would guess we eat more meat here, since we are wealthier and can afford it. With this scant information, I might conclude that India has a high rate of diabetes, higher than the US in some places, that coincides with a more vegetarian diet. This is only an association, not cause-and-effect. And it's hardly scientific. Also, it may not be an issue of meat-eating vs. vegetarianism at all, but an issue of type of carbohydrate consumed.

A 2003 article in the British Medical Journal reported:

"Although India's cereal production has soared, the cultivation of pulses, fruits, and vegetables has stagnated. Indian nutritionists say the consumption of fruits and vegetables in India is abysmally low - less than 150g a day, against the recommended 400 g."

One last statement, in the form of a piece of advice, from Dr. Rao:

"Many believe that one should not eat sugar in any form, one should restrict the amount of rice in a meal, one should not eat potatoes, so on and on. But all of them are restrictions on carbohydrate foods, which are not at all harmful as compared to fat foods."

What a curious conclusion, given that as the consumption of fat in this country declined (and the consumption of carbohydrates rose), the incidence of diabetes rose.

What's the answer? Eat less fat, and more carbohydrate? Or the other way around? Diabetes is one perplexing disease.________

Impact of Genes on Cholesterol Levels

What impact genes, what impact environment?

Ruby asked:

I often hear it said that genetics has a lot to do with a person's cholesterol levels.

1. Is that true?
   
2. If so, I wonder how many people chalk their high cholesterol up to genetics, when really they could make some changes to their diet to bring it down naturally?

While some high cholesterol is governed primarily by genes and is resistant to dietary and lifestyle changes, many other types, genetically rooted or not, respond well to these changes.

I know of at least one type of genetically transferred high cholesterol: familial hypercholesterolemia (FH). It results from a defect in a gene on chromosome 19 (shown). It's resistant to dietary and lifestyle therapies. High dose statins are usually given.

I looked up the prevalence of FH in the US. It looks to be about 1 in 500 or 0.20%.² So, if you had a group of 10,000 people, only 20 might have FH. It's considered rare.

How Many People In This Country Have High Cholesterol?

The age-adjusted prevalence for cholesterol levels over 200 mg/dl among white men age 20 and older is 47.9%, among white women is 49.7%.³ The prevalence is higher in older age groups. So, if you had a group of 10,000 adults, about half of them, or 5000, might have cholesterol over 200.

Clearly, many more people have high cholesterol than can be accounted for by an inherited disorder such as FH - a disorder not amenable to dietary and lifestyle changes.

Ruby makes a good point in the second part of her comment.
________¹ With any condition, there's no negating the effect of genes. We're alive because of genes. However, in my mind, conditions lie along a nature-nurture continuum. I've always liked this phrase: "Genetics loads the gun; environment pulls the trigger."
² CDC: Genetic Causes of Monogenic Heterozygous Familial Hypercholesterolemia: A HuGE Prevalence Review
³ American Heart Association: Cholesterol Statistics

Jane Brody's Cholesterol Goes Up

Melinda sent this article from yesterday's New York Times:

Cutting Cholesterol, an Uphill Battle, by Jane E. Brody

Jane Brody is the author of Jane Brody's Good Food Book: Living the High-Carbohydrate Way, among others. She's an award winning columnist for the New York Times, Personal Health section. Here's a short bio.

In the article, Ms. Brody described her battle with cholesterol:

Baseline readings (Includes exercise of 60-90 minutes/day):
total cholesterol 190 - 205 mg/dl.

December 2006 readings:
total cholesterol 222
LDL 134
HDL 69
VLDL 19
triglycerides 95

... LDL was high so she cut out cheese, lost 3 pounds, took plant stanols, continued exercising 60-90 min/day ...

March 2007 readings:
total cholesterol 236
LDL 159

.... She further limited red meat, stuck to low-fat ice cream, ate more fish, increased fiber, took fish oil, exercised 60-90 min/day...

June 2007 readings:
Total cholesterol 248
LDL 171

Her doctor’s conclusion: "Your body is spewing out cholesterol and nothing you do to your diet is likely to stop it."

Ms. Brody is concerned that her lipid-based risk factors may predispose her to a heart attack or stroke. She decided to take a statin.

Keep in mind that as the percentage of calories contributed by fat in Ms. Brody's diet declined, the percentage contributed by carbohydrates likely rose.
________
Do you agree with Ms. Brody's doctor's conclusion?

The following is an oft-cited study that sought to evaluate the relationship between the amount and type of carbohydrate consumed, and risk for coronary heart disease (CHD). It appeared in the American Journal of Clinical Nutrition in 2000.

A Prospective Study Of Dietary Glycemic Load, Carbohydrate Intake, And Risk Of Coronary Heart Disease In US Women

Over 75,000 women (part of the Nurses Health Study) with no previous diagnosis of diabetes, heart attack, angina, stroke, or other cardiovascular diseases were followed for 10 years. Their diets were analyzed periodically during that time.

Findings:

"Dietary glycemic load¹ was directly associated with risk of CHD after adjustment for age, smoking status, total energy intake, and other coronary disease risk factors."

Those who consumed the most daily carbohydrate (around 226 grams/day) fell into the highest quintile for GL, and had almost double the risk for CHD than those who consumed the least carbohydrate (around 144 grams/day).

The following piece of data stood out for me, in light of the theme of my recent posts:

"Dietary glycemic load did not appear to be determined by any particular food; the 2 most important contributors to dietary glycemic load in this population were mashed or baked potatoes (8%) and cold breakfast cereals (4%)."

The Lipid Profile Doesn't Tell The Whole Story

It's unfortunate that glucose and insulin markers weren't presented, if they were evaluated at all, since the authors of the above study state:

"Insulin resistance, hyperglycemia, and related metabolic disorders have long been recognized as important risk factors for CHD."

And that:

"High dietary glycemic load apparently induces [those states of] hyperglycemia and hyperinsulinemia, which can lead, in turn, to hypertension, dyslipidemia [high cholesterol, LDL, etc.], and possibly impaired fibrinolysis and thrombosis, all of which can increase the risk of CHD."

Do you agree with Ms. Brody's doctor's conclusion? That nothing she could do to her diet could improve her risk factors for CHD?
________¹ In this study, glycemic load was the product of the glycemic index of a food and its carbohydrate content.

Breakfast Cereals Are An Easy Sell

Breakfast cereals are also a major contributor to the prevalence of diabetes and heart disease in this country.

Draw your attention to the blue-box display that's featured prominently at the end of the aisle in the bottom photograph in my previous post. (See photo at right. Click to enlarge.)
Here, let me zoom in:



Now, recall what Sans Fromage said in comments:

"How many ways can you spell crap? I’ve looked at the ingredients for most breakfast cereals and even the most basic contain vast amounts of preservatives and sugars. Why are Americans fat? Look no further. Unfortunately cereals are so convenient and ubiquitous that convincing people that they are crap is a hard sell."

Now, have a look at the ingredient list for these boxes of Quisp cereal:

Ingredients: corn flour, sugar, oat flour, brown sugar, coconut oil, salt, niacinamide*, reduced iron, zinc oxide, yellow 5, yellow 6, thiamin mononitrate*, pyridoxine hydrochoride*, BHT (a preservative), riboflavin*, folic acid*.
* one of the B vitamins

Why is There BHT in a Child's Breakfast Cereal?

According to Wikipedia, "[BHT] has been banned for use in food in Japan (1958), Romania, Sweden, and Australia. The US has barred it from infant foods." This is because some studies have shown it to be carcinogenic. The NIH says that BHA, a close chemical relative to BHT, "is reasonably anticipated to be a human carcinogen." The state of California lists BHT's cousin, BHA, as a "Chemical Known to the State to Cause Cancer". Even the World Health Organization says "There is sufficient evidence for the carcinogenicity of butylated hydroxyanisole [BHA] to experimental animals."

Just a Bowlful of Sugar

Aside from the controversy surrounding the inclusion of a possibly carcinogenic compound, one serving (1 cup) of Quisp cereal supplies a whopping 12 grams of sugar, 23 grams of carbohydrate, resulting in a fairly high glycemic load of 16.¹ When you consider that "The long-term consumption of a diet with a relatively high GL is associated with an increased risk of type 2 diabetes and coronary heart disease.", is it any wonder we're seeing a spike in these conditions in this country, especially among our children?

Why is Quaker Oats marketing, to use Sans Fromage's term, crap, to children? When I walked by this display, a young girl, maybe 5 or 6, picked up a box (notice how low to the ground the display is) and begged her mother to buy it. The mother conceded.________¹ It isn't just sugar in a food that causes a high glycemic load (GL). Cheerios has only 1 gram of sugar per 1 cup serving, yet its GL is still a relatively high 13. That's owing to the highly refined state of its carbohydrates.
These figures were provided by the site NutritionData.com. It's worth a visit!

Photos: Homegrown

What Diet Is That?

A few more observations on my continuing experiment with a lower-carbohydrate diet:

1. I'm not a vegetarian but I think this diet would be difficult for vegetarians to follow. Dr. Atkins claims that vegetarians, but not vegans, can follow it.
   
2. I've been eating more meat. My food bills are higher because of it.
   
3. I've been spending even more time cooking than I usually do.
   
4. The above 3 points lead me to think that eating an Atkins-like diet requires more time, expertise, money, and (assuming one reason vegetarians chose to be vegetarians is to reduce the damage factory farming has on the environment) perhaps a shifting of social priorities, than, say, eating a bowl of cereal or pasta.

I'm still thinking over that last point. You might say that any diet, any way of eating, requires similar resources.

What Is The Optimum Diet?

Barbara made a good point in comments:

"When you think about it, the human race survived for a very long time (with healthy bones and teeth supposedly) before grains and sugar were introduced to the diet mix."

It's true, we'd be foolish not to consider how we evolved to eat. So, I'm left trying to find a diet that:

1. Is best suited to a contemporary human's physiology.
   
2. Can sustain the world's ballooning population. (Dr. Cordain, of Paleolithic Diet fame, claims: "Without cereal grains, there would be massive starvation of unprecedented proportion on the planet.")
   
3. Has the least negative impact on the environment.

What diet is that?

For sure, it's not this:



________
Photos: Homegrown. The cereal aisle at my local food market.

More D, Please

The following article is brought to us by Lavender Blue:

Sunshine Helps In The Fight Against Breast Cancer

I can't keep up with all these great studies rolling in about vitamin D. There are so many. Vitamin D is integral in:

• Preserving bone
  
• Supporting muscle strength
  
• Preventing cancer
  
• Decreasing heart disease risk
  
• Decreasing diabetes risk
  
• Boosting immunity
  
• ... Related to boosting immunity: decreasing risk for autoimmune diseases such as multiple sclerosis, lupus, inflammatory bowel disease, rheumatoid arthritis, etc.

It's going to change our recommendation for vitamin D in the future, I can see that. Right now, the recommended Adequate Intake is between 200 and 400 IUs/day. I can see that being increased to 800 IUs in a few years. (The recommending body for nutrients, The Institute of Medicine, works slowly.) In the mean time, and I can't believe I'm doing this since I'm as white as all-purpose flour, I've begun to have quick, unprotected sun exposure. According to Reinhold Vieth of the University of Toronto (who wrote the excellent, doggedly researched, profusely cited review article, Vitamin D Supplementation, 25-Hydroxyvitamin D Concentrations, and Safety) all I'll need is about 15 or 20 minutes, tops:

"To offer some perspective here, an adult with white skin [pigmented skin takes longer to manufacture vitamin D], exposed to summer sunshine while wearing a bathing suit, generates about 250 µg (10,000 IUs) of vitamin D3 in 15 to 20 minutes; longer exposure generates no more vitamin D." - Reinhold Vieth, Vitamin D Insufficiency: No Recommended Dietary Allowance Exists For This Nutrient

Since that's not going to do the trick for me from November through February¹: I've added vitamin D₃ (cholecalciferol) oil-based supplements to my regimen. When I run out, 3 ounces of oily fish, e.g. sardines or salmon, provide between 300-400 IUs - the amount found in many supplements. ________¹ Linus Pauling Institute, Preventing Osteoporosis Through Diet And Lifestyle Photo of basking prairie dog compliments of Manitoba, Canada's Fortwhythe Alive Nature Center.