The Nutrition Debate #272: Falling asleep at the wheel?

An article in The Washington Post caught my attention: “Falling asleep causes 1 in 5 auto crashes.” The finding is based on new research of 14,268 crashes from 2009-2013 in which one vehicle was towed from the scene. The AAA Foundation for Traffic Safety analyzed the data and commented, “Like distraction, there are limitations in relying on crash-involved drivers to realize, remember and willfully report their level of impairment.” Therefore, the AAA investigators said, “This study leveraged findings from trained crash investigators, as opposed to police reports, as a source of data.”

Okay, as a practiced debunker of bogus or biased “research,” I could take issue at the “overreach” of their study design, the “factors” taken into consideration, the “confirmation bias” of the AAA and their “public health” agenda and advocacy disposition, but I won’t. The reason this caught my attention is that I could relate. In years past I almost killed myself (and sometimes another) on numerous occasions – too numerous to recount – by nodding off behind the wheel.

The reason, however, was not “fatigue” (lack of sleep) in the usual sense; it was low blood sugar (NOT hypoglycemia). Now it’s true that I have been a diagnosed type 2 diabetic for 28 years, which means I have probably been a type 2 for 30 to 35 years (since I was in my late 30s). This also means I was undoubtedly a pre-diabetic or 5 or 10 years before that, going back to my late 20s or early 30s. Why is this relevant? I will cite a source for the “history” of the development of type 2 diabetes – the mechanisms – a little later, but first I’ll cite some examples of common behavior that everyone can relate to.

In a few days we are going to celebrate Christmas. In our house, some adults eat almost as many Christmas cookies (and other baked goods full of sugar and butter) as the children do. We give ourselves “a pass” a few times a year to indulge in the goodies we would normally pass on. We also have fresh in our memories a similar feast of Thanksgiving just a few weeks before when we ate loads of starchy vegetables and stuffing and gravies passed around the table “family style.” It’s a wonderful tradition. And it’s equally a tradition for some overstuffed family members to “feel sleepy” after a “big meal.” Others go for a walk in the brisk late-fall air to increase their peripheral circulation and stave off that sleepy feeling.

Now we all know that we (most of us, except the cook!) are not suffering from a lack of sleep, or even a few stressful days leading up to the big meal. We are suffering from a lack of blood in the peripheral areas (arms and legs) and brain while the blood concentrates in the central areas to process, digest and absorb all the “energy” we ate. The extremities get short shrift, as they should. The body does this autonomically. It’s natural. Animals like big cats take a long nap after devouring enough of their catch to carry them days or even longer until they are fortunate enough to make another.

But the “big meal” syndrome is only part of the picture. People who have, or almost imperceptibly are beginning to have, a compromised glucose metabolism – like I was in my late 20s and early 30s – are simultaneously experiencing a different physiological phenomenon: our blood sugar routinely becomes elevated (“spikes”) above the normal +/- 140mg/dl after a meal. People with a healthy glucose metabolism never have a blood sugar above 140mg/dl, even after a big meal. But people with a compromised glucose metabolism, who eat a lot of carbs, always spike higher.

This is the result of the loss of the 1^st insulin response in which the pancreas produces a spurt of insulin in anticipation of and at the onset of eating and the beginning of insulin resistance in which the destination cells (muscles, etc.) for the glucose circulating in our blood have developed resistance to the insulin that is transporting the glucose. The result is that the glucose is not “taken up” as quickly. It continues to circulate and we have “high blood sugar.” Then, slowly, for the prediabetic (but not the un-treated T2), what goes up must come down. Your blood sugar crashes, and you “feel tired.”

If you’re interested, the mechanism of how someone who is genetically predisposed to having a dysfunctional glucose metabolism, and who eats the Standard American Diet (SAD), is explained by the 2008 ADA convention keynote speaker and Banting Award winner Ralph DeFronzo, MD, in The Nutrition Debate #99, “Natural History of Type 2 Diabetes.”

But for the less technically inclined, just know this: If you’ve gained weight eating the diet recommended by the USDA’s Dietary Guidelines, and the medical establishment (ACC/ADA), and their members who have no training in nutrition, then consider that it may be that your glucose metabolism is starting to unravel. If you “feel sleepy” after a big meal, it may be more than just all your blood rushing to the stomach to deal with your excesses. It may be a sign that you need to cut back on sugars and starches (i.e. on all dietary carbohydrates) that you eat. The life you save may be your own, or your family’s.