Sleeping poorly night after night—because you are trying to burn the candle at both ends or you work night or rotating shifts—has long-term health consequences. People who don’t average at least six hours of sleep a night are more likely to be overweight or develop various medical problems. New research from Harvard-affiliated Brigham and Women’s Hospital shows that lack of sleep plays a complex and powerful role in the development of type 2 diabetes. Among volunteers who lived in a sleep lab for several weeks, their bodies made less insulin after meals when they got under 5.5 hours of sleep a night for three weeks. As a result, their blood sugar levels went haywire. Some of the people had blood sugar levels high enough to have been diagnosed as prediabetic.
The term “personalized medicine” is still something of an abstract idea. In an audacious experiment, Stanford molecular geneticist Michael Snyder gave it a face—his own—and showed what it can do. Snyder and a large team of colleagues first sequenced his DNA, revealing his complete genetic library. Then they analyzed blood samples he gave every few weeks for two years. This was akin to taking a 3-D movie of his inner workings to observe how genes, the molecules that read and decode them (RNA), the proteins they make, and other substances interact during health and illness. The team saw how Snyder’s body responded to a cold at the very beginning of the study. Midway through, they watched as molecular changes wrought by a respiratory infection tipped him into full-blown diabetes.
Most of the changes that come with pregnancy—growing a belly “bump,” being tired, mood swings, cravings for particular foods, and the like—are normal, temporary, and harmless. Two other changes, pregnancy-related high blood pressure and diabetes, may have long-lasting implications for heart health. The development of high blood pressure during pregnancy is known as preeclampsia; pregnancy-related diabetes is called gestational diabetes. They are different from “regular” high blood pressure and diabetes because both are “cured” by delivery. A new study published this week in the journal Circulation suggests that these complications boost a woman’s risk of cardiovascular disease during middle age.
Type 1 diabetes, once called juvenile-onset diabetes, takes a toll on health and longevity. Some people, though, have managed to live with the disease for decades. Since 1970, almost 3,500 men and women who have lived with type 12 diabetes for a half century have been recognized by the Joslin Diabetes Center in Boston with bronze 50-year medals. Forty-five of them have passed the 75-year mark. A study that includes several hundred 50-year Medalists is changing experts’ understanding of type 1 diabetes. Many of the 50-year Medalists have no signs of diabetes-induced eye or kidney damage, and some still continue to make small amounts of insulin. This work may uncover new ways to protect people from the damage diabetes can cause and point ways to new treatments for it.
Today, the only reliable way to check blood sugar is by pricking a finger, squeezing out a drop of blood, and placing it on a small test strip attached to a meter. For some people, this means five to ten finger sticks a day. Researchers across the country are exploring pain-free ways to measure blood sugar. University of California, San Diego researchers have developed a titanium sensor the diameter of a quarter that would be implanted under the skin and wirelessly send blood sugar readings to an external monitor. At Northeastern University in Boston, researchers are working on a blood sugar “tattoo” by injecting glucose-detecting nanosensors under the skin. Arizona State University researchers are working to perfect a device that measures blood sugar using tears instead of blood.
More than half of people who live with diabetes eventually develop diabetic neuropathy, or damage to nerves. It can range from merely aggravating to disabling or even life threatening. The first nerves to be affected tend to those in the toes and feet. Diabetic neuropathy can be felt as a tingling in the toes and feet, a constant burning feeling in the feet, sharp pain that may be worse at night, or extreme sensitivity to touch. In some people, it robs the feet of their ability to sense pain. So far, there isn’t a cure for diabetic neuropathy. Controlling blood sugar is the most important step to preventing or managing it. Controlling blood pressure, not smoking, and staying active also help. People with diabetes should have a doctor examine their feet at least once a year, and should check their feet every day or so.
Heart disease, stroke, diabetes, asthma, osteoporosis and other common chronic diseases are often blamed on genes, pollution, or the wear and tear caused by personal choices like a poor diet, smoking, or too little exercise. An intriguing hypothesis is that these and other conditions stem from a developing baby’s environment, mainly the womb and the placenta. During the first thousand days of development, from conception to age 2, the body’s tissues, organs, and systems are exquisitely sensitive to conditions in their environment during various windows of time. A lack of nutrients or an overabundance of them during these windows, so the thinking goes, programs a child’s development and sets the stage for health or disease.
More than 18,000 clinical trials are underway right now in the United States, covering nearly every aspect of health and disease. Harvard Heart Letter editor P.J. Skerrett describes his experience as a volunteer in a clinical trial called TINSAL-T2D at the Joslin Diabetes Center in Boston.
High-fructose corn syrup has been blamed for causing the paired epidemics of obesity and diabetes that have swept the U.S. and many other parts of the world. The real problem may be fructose, warned Dr. Robert H. Lustig, a professor of pediatrics at the University of California, San Francisco, in a talk at Harvard School of Public Health. Fructose, sometimes called fruit sugar, is just as abundant in refined sugar as it is in high-fructose corn syrup. When the liver metabolizes fructose, it makes triglycerides (a form of fat) and can lead to insulin resistance, a precursor of diabetes. Although researchers haven’t completely connected all the dots between high intake of fructose from sugared soft drinks, juices, and sugar-sweetened foods and the onset of diseases like diabetes and nonalcoholic fatty liver disease, the findings so far offer another reason to limit sugary beverages and foods.