DEAR DR. BLONZ: I must begin monitoring my intake of foods that raise my blood sugar level. Could you please provide some basic info about blood sugar? -- Y.M., Berkeley, California
DEAR Y.M.: A good way to begin is to think about rain -- a definite obsession here in Northern California. The rivers, lakes and even the water systems in our homes and towns are set to handle certain amounts of rain. A torrential downpour, or excessive rain on a regular basis, overwhelms the capacities of the various systems, and water ends up in places where it's not expected or desired. The end result, as we have seen in recent seasons, is flooding, property damage and injuries.
Similarly, the human body has various systems designed to handle an influx of carbohydrates.
Set aside the rain analogy for a moment. Glucose, a simple sugar, is the preferred fuel of the brain and the rest of the nervous system. It is an anaerobic fuel that releases energy without extra oxygen. It's what allows us to dash across the room to catch a falling object, or run to catch a bus without first needing to take several deep breaths to increase the level of oxygen in the bloodstream.
The body works best with a metered entry of glucose into the bloodstream, which happens when carbs come from a whole-grain starch and are part of a varied meal. After we eat complex carbohydrates, the digestive system breaks them down into simple sugars (mostly glucose) prior to absorption. After that, there are specific enzyme systems that work on the glucose to provide its unique benefits to the body.
Now back to the rain. With a normal downpour, the gutters on our houses and the drainage systems of our towns handle the water with little incident. But when you consume too much added sugar from sweets or sodas, especially on an empty stomach, it's like a deluge descending on your home.
When an excess of sugar enters the blood, the body has to scramble to assert control. Alternate pathways must be used, and if this occurs on a regular basis, the conditions become right for the development of our most troublesome diseases and conditions: heart disease, diabetes, diabetic neuropathies, obesity, hypertension, arthritis and even cancer. There is no way to sugarcoat the science.
Sugar is not bad in itself, but an excess of it tends to shove our bodies' systems in the wrong direction. A study in the Feb. 3 issue of JAMA Internal Medicine compared U.S. adults who consume no more than 10 percent of their calories from added sugar with those who have more. It reported that individuals who habitually consumed between 10 and 25 percent of their calories from added sugar had a 1.3 times higher risk of cardiovascular mortality. Those having 25 percent or more calories from added sugar had 2.75 times the risk of dying from cardiovascular disease.
Strive to keep your intake under control by opting for a diet that is primarily plant-based with a hefty percentage of whole foods. Read your labels, and pay specific attention to "added sugar" -- not the sugar naturally present in a whole food, but that which is purposefully added during processing. The FDA has proposed a revision of the Nutrition Facts label to include a specific listing of added sugars. I welcome this step forward.
Don't obsess over every gram; think big picture. This message is especially important for the growing bodies of children, teens and young adults.
Send questions to: "On Nutrition," Ed Blonz, c/o Universal Uclick, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to firstname.lastname@example.org. Due to the volume of mail, personal replies cannot be provided.