I found “Grocery store bread is processed food” scribbled on a “Post It” next to my laptop, so since I fancy myself a lay Type 2 nutrition educator, it must be that it was my intention to write about it. So, here goes.
Most people grow up eating a lot of bread at home. I did not. I was lucky. My father grew up during the Great Depression. Later he had a good job and regarded our family as too bourgeois to use bread fillers like “Hamburger Helper.” My mother didn’t serve bread with supper either. Like most kids, though, we ate sandwiches. They were a lunch-box staple, together with fruit and cookies, for school every day.
Store-bought bread, at least the kind sold in a plastic wrapper, has to have a long shelf life. Silvercup is the brand I remember. It was white and spongy. I didn’t learn until recently that what made it spongy was sugar. Here’s a challenge: Look at the label on any loaf of bread sold with a wrapper in the supermarket. I defy you to find one where sugar, HFCS, or some other form of sugar, is not, after flour and water, the third ingredient.
The glycemic index is a scale from 1 to 100 which measures the rate at which a food will raise blood sugar. A slice of white bread is 100 on the glycemic index! No other food will make a Type 2, or Pre-diabetic or Insulin Resistant’s blood sugar rise faster and farther than white bread. Two slices of Walmart's white bread contain 23g of carbohydrate (including added sugar) and 5g protein (from gluten in the flour).
Why is bread the very definition of a high-glycemic food? Because it is a PROCESSED food, made from highly REFINED white flour (and 3g of ADDED sugar). Flour starts to break down into glucose when enzymes in saliva contact it! And sugar is a simple carb that only needs to divide once (in your mouth!) to become glucose.
Why is a processed food like white bread so much worse for you and your blood sugar control than say an apple? (To be clear, I’m not advocating you eat, as we learned as kids, “an apple a day.” I just want to explain the difference.) The carbs in white flour are 100% glucose molecules. Glucose makes your blood sugar rise.
The principal nutrients of an apple are simple sugars: sucrose (a disaccharide of glucose and fructose. Glucose and fructose are monosaccharides. The glucose molecule goes into your blood to be circulated and taken up for energy. The fructose molecule does not. It goes directly to your liver, for detoxification. If you need more glucose for energy, your liver converts the fructose to glucose. If you don’t need more, it stores it as glycogen. But if the liver is already full of glycogen, it uses a process called “de novo lipogenesis” to convert the excess fructose to fat. That’s right! The liver makes fat from the excess sugars glucose and fructose.
An apple also has high fructose content. After water (86%) and fiber (3%) the remaining 11% of an apple by weight are simple sugars: 20% the disaccharide sucrose (half glucose/half fructose), 23% “free” glucose and 57% “free” fructose. The “free” molecules are monosaccharides. So, when the sucrose breaks down to monosaccharides, an apple is 33% glucose and 67% fructose. Only the 33% glucose in an apple raises your blood sugar versus 100% in a slice of white bread. You already know what the fructose does to your liver. Ugh!
Years ago, I met a nurse in a swimming pool (in Mexico) who told me her husband had a fatty liver. This was at least a decade before Non-Alcoholic Fatty Liver Disease (NAFLD) was among the conditions associated with Metabolic Syndrome. We now know that you don’t have to be obese to have NAFLD. It’s the visceral fat within and around your internal organs that causes NAFLD. I wish I’d known that in the swimming pool in Mexico.Today, white bread is the standard bearer for the “bad boy” foods we’ve eaten ever since we carried a sandwich to school eons ago. And government still tells us to eat it. Look at Choose My Plate from the HHS/USDA and Create Your Plate from the American Diabetes Association, respectively. But don’t expect the government to change. Agribusiness and Big Pharma have too much at stake to let that happen any time soon.