October 25th, 2013
02:08 PM ET
Here's a roundup of five medical studies published recently that might give you new insights into your health, mind and body. Remember, correlation is not causation – so if a study finds a connection between two things, it doesn't mean that one causes the other.
Some obesity may be related to slow metabolism, really
"Slow metabolism" as an explanation for obesity has been largely knocked down by doctors as inaccurate. But University of Cambridge researchers showed in a new study that mutations on a particular gene slow metabolism, which may be linked to obesity in some people.
Previous research had shown that mice without the gene KSR2 tended to become overweight.
In this study, researchers sequenced the DNA of 2,101 people with severe early-onset obesity and 1,536 people who were not obese. They saw that mutations in KSR2 were associated with "hyperphagia (increased appetite) in childhood, low heart rate, reduced basal metabolic rate and severe insulin resistance."
Fewer than one in 100 people have KSR2 mutations, and some of those do have normal weight, BBC News reports.
This genetics research could have implications for developing drugs that help people with obesity and type 2 diabetes, the study said.
High blood sugar linked to memory problems
Past studies have suggested that diabetes raises the risk for Alzheimer's disease although it's not entirely clear why. New research finds that even in people who don't have diabetes, chronically higher blood glucose levels are associated with poorer outcomes in the brain.
This study looked at 141 people, average age 63, without diabetes or pre-diabetes. No participants were overweight or had memory and thinking impairment.
On cognitive tests, participants with lower blood glucose levels performed better in terms of delayed recall, learning ability and memory consolidation than those with higher levels. What's more, those with higher levels tended to have smaller volumes in the hippocampus, a sea horse-shaped brain structure crucial for memory.
“These results suggest that even for people within the normal range of blood sugar, lowering their blood sugar levels could be a promising strategy for preventing memory problems and cognitive decline as they age,” study author Dr. Agnes Flöel of Charité University Medicine in Berlin said in a statement. “Strategies such as lowering calorie intake and increasing physical activity should be tested.”
This study received significant media attention, but Dr. Jane Chiang, the American Diabetes Association's Senior vice president of medical affairs and community information, said she has a lot of concerns about the way it was conducted. The participants weren't entirely "healthy," according to their blood glucose levels – in fact, they may have diabetes and not know it, she said.
A bigger concern, Chiang said, is that older adults aren't recommended to have a strictly regulated "normal" blood glucose in the first place. Low blood sugar presents dangerous risks of falls and seizures, so the American Diabetes Association discourages tight blood sugar control in older adults.
August 12th, 2013
04:05 PM ET
You are looking at a woman's face; the contours and features seem so familiar. You see the billowing brown hair, the broad smile, the almond-shaped eyes. You may even be able to describe things about her: Famous talk show host, actress in "The Color Purple," philanthropist.
You feel a familiar pang of frustration because the name seems to be in your grasp, but you cannot come up with it.
The person, of course, is Oprah Winfrey. The inability to conjure the name of such a famous face, for some people, is one of several symptoms of a brain disease called primary progressive aphasia (PPA).
The disease "affects a person's ability to communicate," said Tamar Gefen, a doctoral candidate at the Cognitive Neurology and Alzheimer's Disease Center at the Feinberg School of Medicine at Northwestern University, adding that the disease attacks language centers in the brain.
"Slowly, over time a person loses the ability to name, comprehend, write and communicate," Gefen said.
The loss is not fleeting, but persistent, progressive, and socially crippling. Patients do not just have difficulty naming Oprah, but can have problems recognizing their own family members or friends. All of that makes having an accurate test for the disease important.
May 21st, 2013
10:47 AM ET
Sticking to a Mediterranean diet may not just be good for your heart, it may be good for your brain as well, according to a new study.
Researchers in Spain followed more than 1,000 people for six and a half years, and found that participants who were on a Mediterranean diet and supplemented that diet with extra nuts or olive oil performed better on cognitive tests at the end of the study period than the control group, which followed a lower-fat diet. The study was published Monday in the Journal of Neurology, Neurosurgery and Psychiatry.
"We found that a Mediterranean diet with olive oil was able to reduce low-grade inflammation associated with a high risk of vascular disease and cognitive impairments," said Dr. Miguel Martinez-Gonzalez, the chairman of preventive medicine at the University of Navarra in Spain and a study author.
The Mediterranean diet is devoid of processed foods and bad fats, and high in whole grains, nuts, fruits and vegetables, legumes, fish and even red wine - all things that are high in antioxidant and anti-inflammatory compounds. These types of foods are known to help reduce vascular (circulatory) damage, inflammation and oxidative (free radical) damage in the brain. FULL POST
May 2nd, 2013
07:02 AM ET
Kids don't all learn at the same pace, or in the same way. Extra tutoring doesn't always help either, but for some it helps a lot. Why?
Researchers, publishing this week in the journal Proceedings of the National Academy of Sciences, believe the answer is in the brain. By looking at the structures and wiring of children's brains, they've developed a method of predicting who will benefit most from tutoring.
This doesn't mean, however, that you will be seeing brain scans in every school.
"What we’ve done is much more modest, in terms of trying to understand what are the systems that underlie individual differences in response to math tutoring," said Vinod Menon, professor at Stanford University School of Medicine and senior author of the study.
About this blog
Get a behind-the-scenes look at the latest stories from CNN Chief Medical Correspondent, Dr. Sanjay Gupta, Senior Medical Correspondent Elizabeth Cohen and the CNN Medical Unit producers. They'll share news and views on health and medical trends - info that will help you take better care of yourself and the people you love.