MY FRIEND SAM, who is tiny and exercises several times a day, recently learned that she was pre-diabetic and was advised to eat less sugar. She had, admittedly, been consuming mostly lattes and cookies until dinnertime, when she usually ate a healthy meal.
(Disclosure: I like sugar and sugary foods, am hounded by the food police when I add an extra packet to my tea, and read with special interest medical reports on sugar and disease.)
Type 2 diabetes (T2DM) is generally thought to occur in people with weight problems, especially those with sedentary lifestyles, but thinner people are not exempt.
In both Type 1 and Type 2 diabetes, though for different reasons, insulin is no longer doing its job of processing sugar (glucose), which then circulates at high levels in the bloodstream. High blood sugar can cause connective-tissue damage and chronic inflammation, leading to long-term effects, especially on the nerves, the retina and the kidneys. With T2DM, high blood sugar measurements can precede the development of full-blown diabetes by ten years or so, during which time circulating glucose may have begun causing complications.
The reasons for high blood sugar and eventually for T2DM in thinner people include some disease conditions (autoimmunity and “fatty liver”) along with genetics, inflammation and stress. In the past, autoimmunity was believed to cause only Type 1 diabetes, in which the body’s immune system destroys the pancreatic cells that produce insulin, usually at a young age, after which sufferers are dependent on insulin from outside sources.
Recently, lines between the two types of diabetes have blurred. Now Type 1 diabetes is also seen occurring later in life, when it looks more like Type 2. In the past, T2DM was the result of insulin resistance, when the body continues to produce insulin but the cells can’t use it efficiently to process glucose. Being over age 45 is now considered a risk factor in itself for diabetes, along with excess weight, high blood pressure, family history, etc.
In stressful situations, high levels of the “stress hormone” cortisol raise blood sugar levels to deal with the crisis. But chronic stress, from hours spent in rush-hour traffic or long-term anxiety about jobs or health, causes chronically elevated cortisol and thus chronically high blood-sugar levels, even with a perfect diet and regular exercise.
Lack of sleep can provoke a reaction similar to insulin resistance, and high sugar levels remain circulating in the blood. Getting enough sleep, however, measured by the ability to wake up without the help of an alarm clock, can be a challenge.
On the subject of sugar alone, most of the health news is bad. Besides diabetes, there are wrinkles — as many as from sun exposure and smoking – caused by a process called glycation that causes sugars to attach to the proteins in collagen and elastin. The same mechanisms by which high blood-sugar levels cause tissue damage and inflammation spur aging effects on the skin.
Sugar-curbing advice has even spread to wine. Wines with less sugar, such as Pinot Grigio and Cabernet Sauvignon, called “bone dry,” have less than one gram of sugar in a 5-ounce glass compared to about 12 grams of sugar in a 4-ounce glass of vintage port.
Low blood sugar can also create problems. Low glucose levels have been shown to make married people angrier at their spouses and more likely to lash out aggressively, according to research at Ohio State University, in which participants were given voodoo dolls representing their spouses along with 51 pins. To control anger and aggressive impulses, along with all other mental activity, the brain consumes about 20 percent of our calories, explains Ohio State psychology professor Brad Bushman. To raise blood glucose when needed, however, complex carbohydrates are, of course, preferable to candy bars.
Early symptoms of diabetes can include increased thirst, hunger and urination, especially at night, as well as fatigue and unexplained weight loss. More serious indicators are blurred vision, numb or tingling hands or feet and sores that don’t heal quickly.
To reduce the risk of diabetes, olive oil helps boost insulin sensitivity, while vegetables, whole grains and nuts lower blood sugar. Because fiber slows sugar absorption, whole foods like oranges are a better choice than the juice.
Most of the other risk-lowering tactics involve movement. An easy one is light exercise after each meal, like a stroll around the block, but it must be done 30 minutes after eating. The resulting muscle contractions continue to clear sugar from the blood for about three hours afterwards.
Moving for a few minutes every half-hour throughout the day keeps the metabolism working better to maintain low glucose levels. Recent research in New Zealand on people whose blood sugar levels remained severely elevated for hours after eating showed that three 10- to 12-minute periods of exercise worked better than one 30-minute period. And within the short sessions, blood sugar stayed low over a 24-hour period when high-intensity intervals — one minute walking as fast as possible, or one minute of high-intensity upper-body resistance training with exercise bands – were alternated with minutes of regular exercise.
But keep the risks of long-term stress in mind. Don’t worry too much about pre-diabetes. And take heart from the axiom: Pre-anything means you have nothing.
— Mary Carpenter