Insulin is the hormone that facilitates the transport of blood sugar (glucose) from the bloodstream into cells for use as fuel. In healthy individuals it is secreted by the pancreas in response to the normal increase in blood sugar that occurs after a meal. With insulin resistance, the normal amount of insulin secreted is not enough to move glucose into the cells - thus the cells are said to be "resistant" to its action, and the pancreas is prompted to secrete higher amounts. This excess insulin drives the body to store fat and can lead to diabetes, a risk factor for heart disease. And new research suggests that insulin resistance may also increase the risk of Alzheimer’s disease. Investigators at Iowa State University examined brain scans of 150 middle age adults whose average was 60 who showed no signs of memory loss. The scans were aimed at determining if study participants with higher levels of insulin resistance used less blood sugar in particular regions of the brain, especially those areas most susceptible to Alzheimer’s. If so, the brain would have less energy to deal with information and function. The results showed that insulin resistance was associated with significantly lower regional cerebral glucose metabolism, which in turn may predict worse memory performance. Based on their findings, the researchers noted that problems regulating blood sugar might affect cognitive function regardless of age. Even people with mild or moderate insulin resistance might have an increased risk for Alzheimer’s because they’re showing many of the same sorts of brain and memory relationships wrote lead researcher Auriel A. Willette, Ph.D. Fortunately, you can help restore normal insulin sensitivity with diet – emphasize low-glycemic index food – and exercise.
We’ve heard a lot lately about the toll excessive sitting – at work, in traffic, at home in front of the TV or computer – can take on health. Now a study from Australia has shown that replacing sitting with two hours of standing or stepping (which includes walking and running) can help improve your health. Researchers at the University of Queensland investigated the effects of spending more time on their feet among 782 men and women, ages 36-80. All the study participants were provided activity monitors that can accurately determine how long each one spent sleeping, sitting, lying down, or standing and stepping. The participants wore the monitors on their thighs for 24 hours a day for seven days. Then, the researchers used a statistical technique called isotemporal analysis to estimate the potential impact on health of switching from sitting to standing or stepping. They determined that an extra two hours per day standing was linked to approximately 2 percent lower average fasting blood sugar levels, 11 percent lower average triglycerides, a boost in HDL (“good”) cholesterol and a 6 percent average drop in the ratio between total and HDL cholesterol. Two hour extra stepping time was associated with an approximately 11 percent lower BMI and a 7.5-centimeter (about 3 inches) smaller waist circumference.
My take: We know from other studies that habitual sitting is related to increased deposits of adipose tissue around the heart (pericardial fat), a change linked to cardiovascular disease that can impact the arteries that serve the heart. While the Australian researchers acknowledge that more and larger studies are needed to confirm their findings, the results of this one are useful. They show that health can be improved with simple habits of lifestyle, including the amount of time you spend standing and stepping. I’m in favor of anything that encourages you to move regularly. Spending a little more time on your feet would be a good start.
We know from earlier studies that walnuts are beneficial for heart health. New research from Yale now indicates that eating walnuts can prompt beneficial improvements in diets. Investigators recruited 112 people at high risk of diabetes (based on their weight, blood sugar or blood pressure levels). Half the participants added about two ounces of walnuts per day to their diets for six months and then stopped eating walnuts for six months. Half of all the participants received nutrition counseling, including the instructions to cut calories from other sources to offset the walnuts added to their diets. The other participants had no nutrition counseling. During the study the researchers checked all the participants’ cholesterol levels, blood vessel function, blood pressure, blood sugar, body fat and BMI. They reported slight improvements in blood vessel function and total and LDL cholesterol occurred in the walnut group, but the big change was that these participants also began to make healthier food choices than they had previously. As a result of these changes, the overall quality of their diets improved, suggesting that eating walnuts made a psychological as well as physiological difference.
On the heels of a World Health Organization analysis concluding that processed meat is a carcinogen and red meat a “probable carcinogen” comes a report from Germany linking both of these foods with an increased risk of ischemic stroke – the type caused by blockages in blood vessels supplying the brain. Researchers from the University of Wurzberg analyzed data from about 11,000 mid-life men and women in the U.S. with no other risk factors for stroke such as diabetes or heart disease. After following half of this group for an average of 22.7 years, the investigators concluded that those who consumed the most red meat had a risk of stroke that was 47 percent higher than those who ate the smallest amount of red meat. The investigation showed that eating other sources of protein such as poultry, seafood, legumes and nuts posed no additional risk of stroke. Among the men in the study, those who ate the most red and processed meat had a 62 percent higher risk of stroke than men who ate the least amounts of these foods. The researchers also found that the risk of stroke was 24 percent higher among study participants who reported the highest intake of bacon, sausage and other processed meats compared to those whose intake of these foods was lowest. Because this was an observational study, it doesn’t prove that eating red meat or processed meats caused the strokes that occurred among the participants. Instead, it indicates an association between red and processed meat and ischemic strokes.
Lutein is a carotenoid that can help to protect the eyes. Find out if you should take it, and what foods are good sources.
If you or someone you know is getting on in years, you may want to consider supplementing your diet with lutein. Lutein and another carotenoid, zeaxanthin, form the yellow pigment of the retina and absorb blue light, which is a potentially harmful component of sunlight. There is very good evidence that the lutein in food helps protect against cataracts and macular degeneration, which are common age-related eye disorders. The best thing you can do for your eyes this month, and in the future, is to make sure your diet contains plenty of lutein-rich produce, including:
Fruits - mangoes, watermelon and tomatoes are good sources of lutein
Vegetables - corn, sweet potatoes, carrots, peas, squash and dark leafy greens (such as kale, collards and bok choy) provide lutein
In addition to the foods listed above, you can get zeaxanthin from orange bell peppers, oranges, and honeydew melon. I recommend eating five to seven servings of fresh fruits and vegetables per day. If you are unable to get adequate lutein through your diet, you may want to consider a vision-supportive supplement; talk with your doctor.
Are you nervous or anxious before going to the dentist? You’re not alone, but if you avoid regular check-ups or ignore tooth pain because of your fears, your dental health could suffer over time. A recent study from the UK suggests that those fears can be conquered by participating in cognitive behavior therapy - a form of psychotherapy that is effective at addressing other anxiety-related disorders. Researchers surveyed patients at a clinic run by the King’s College London Dental Institute Health Psychology Service. They asked the participants to report their levels of dental anxiety, general anxiety, depression, suicidal thoughts, alcohol use and oral health-related quality of life. Nearly all of the patients reported that they had problems with their teeth, mouth and gums that affected their daily lives and quality of life. All scored high enough on an anxiety scale to suggest a specific fear relating to some aspect of dentistry – the most common concerned injections and dental drilling. After an average of 5 CBT appointments, 79 percent of the patients were able to have dental treatment without sedation while 6 percent opted for dental treatment under sedation. The researchers reported that some of the patients assessed had psychological problems that went beyond dental phobia and required referral for help with those issues.
My take? In addition to CBT, you could consider consulting a hypnotherapist who specializes in phobias. Steven Gurgevich, Ph.D., clinical assistant professor of medicine at the Arizona Center for Integrative Medicine and an expert in clinical hypnosis, notes that all fears - including fear of dental exams and treatment - are learned behaviors, and that anything learned can be unlearned and replaced with something positive. By training your body to relax, you can help desensitize yourself to your dental fears, Dr. Gurgevich said. He also suggests talking to the dentist about your anxiety before scheduling an appointment to have your teeth checked. The American Dental Association (ADA) gives the same advice and explains that getting your fears out in the open allows your dentist to adapt treatment to your needs.
A healthy diet can help the body in its efforts to heal itself, and in some cases, particular foods can lessen the risks of serious illness. To help reduce your risk of some types of cancer, try the following:
1. Avoid polyunsaturated vegetable oils, margarine, vegetable shortening, all partially hydrogenated oils and all foods that might contain trans-fatty acids (such as deep-fried foods).
2. Minimize or eliminate consumption of foods with added sugar and other sweeteners including fruit juices.
3. Increase omega-3 fatty acid intake by eating more cold-water oily fish, freshly ground flaxseed and walnuts.
4. Eat plenty of fresh vegetables and fruit.
5. Use hormone-free, organically raised and grown products whenever possible. Eat shiitake, enokidake, maitake and oyster mushrooms frequently.
6. Drink green tea daily.
Kale is among the most nutrient-dense of all commonly consumed vegetables. One cup provides 1,327 percent of the Daily Value (DV) for vitamin K, 192 percent of the DV for vitamin A and 88 percent for vitamin C. The Tuscan Kale Salad is one of the most popular dishes at True Food Kitchen, a line of restaurants based on Dr. Weil's nutrition insights. Here, on the restaurant's patio in Phoenix, Ariz., watch Dr. Weil and Chef Michael Stebner demonstrate how to make this traditional Tuscan salad that includes strips of Italian black kale, fresh lemon juice, extra virgin olive oil, crushed garlic, red pepper flakes, grated pecorino Toscano cheese and breadcrumbs. These bright, refreshing flavors combine to bring the sunny taste of Italy to your table.
Watch Dr. Weil make Tuscan Kale Salad and get the recipe here!