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Autoimmune Disease, Chronic Disease, Health and Fitness, Nutrition, Obesity, Research

Study clarifies link between dieting, exercise and reduced inflammation

Study clarifies link between dieting, exercise and reduced inflammation

4503404991_13da58b6e6_bIf you’ve ever wondered how dieting and exercise reduce inflammation, read on. According to new research, a compound that our bodies crank out when energy supplies are low could be the link between diet and exercise, and reduced swelling in the body.

When diet, fasting and exercise starve the body for calories, the body increases production of a compound called beta hydroxybutyrate (BHB). This compound has long been known as an alternate source of energy; the new research suggests that BHB can also block the inflammatory response.

In their study, published this week in Nature Medicine online (subscription required), a team of scientists co-led by Yun-Hee Youm and Kim Yen Nguyen at the Yale School of Medicine, discovered that the compound BHB reduces swelling in the body by inactivating a group of proteins, called the inflammasome, that drive the inflammatory response.

The research team used human immune cells and mice to explore the effects of BHB in the body. They found that mice given BHB directly, and mice fed a low-carbohydrate diet (that prompted their bodies to synthesize their own BHB), both benefited from reduced inflammation.

These results are noteworthy because a better understanding of the mechanism that links diet, exercise and inflammation could help scientists develop more effective treatments for inflammatory disorders such as Type 2 diabetes, atherosclerosis and Alzheimer’s disease.

Previously: Newly identified type-2 diabetes gene’s odds of being a false finding equal one in 1 followed by 19 zeroesImproving your health using herbs and spices, Exercise may alleviate symptoms of arthritis regardless of weight loss, Study points to inflammation as cause of plaque buildup in heart vessels and Examining the role of exercise in managing and preventing diabetes
Via ScienceDaily
Photo by Dave Nakayama

Chronic Disease, Obesity, Research, Stanford News

Faulty fat cells may help explain how Type 2 diabetes begins

Faulty fat cells may help explain how Type 2 diabetes begins

heavywaterWhy do some obese people develop Type 2 diabetes while others don’t? New evidence suggests the answer may lie just beneath the skin. A study published this month in the Journal of Lipid Research found metabolic anomalies in the subcutaneous fat of a group of people at risk for diabetes. Basically, fat cells under their skin weren’t very good at storing fat.

That’s a problem because fat that doesn’t get stored in these cells must go somewhere, and it often ends up in other organs, such as the liver, muscle, pancreas and heart. In those locations, there is evidence that too much fat causes “lipotoxicity,” in part by interfering with the messages of the sugar-handling hormone insulin.

The new research, a collaboration between Stanford’s Tracey McLaughlin, MD, and her colleagues here and at UC Berkeley and the National Institutes of Health, used a state-of-the-art technique developed by Berkeley’s Marc Hellerstein, MD, PhD, to monitor fat synthesis and storage in the subcutaneous fat cells of 15 people. All of the subjects were overweight or obese. Half were insulin resistant: Although their blood-sugar levels were normal, their bodies responded poorly to their own insulin, a state that precedes full-blown Type 2 diabetes. (Many scientists think that understanding insulin resistance could lead to preventive strategies for Type 2 diabetes.) The other subjects had normal insulin sensitivity.

Each day for four weeks, the subjects drank a few sips of heavy water, a non-radioactive substance labeled with “heavy” hydrogen atoms that have an extra neutron. After four weeks, the scientists took small samples of the subjects’ subcutaneous belly fat and measured how much heavy hydrogen had been incorporated into the cells’ stored fat molecules and their DNA.

The insulin-resistant subjects had less heavy hydrogen in their fat molecules than the insulin-sensitive subjects, suggesting that their subcutaneous fat cells made and stored less fat during the study. The amount of heavy hydrogen in the DNA of the two groups’ fat cells was the same. This means that the insulin-resistant people were making new subcutaneous fat cells at the same rate as the insulin-sensitive people. The bodies of the insulin-resistant people could generate new fat cells under the skin, but the cells didn’t work quite right.

“This is an important extension of limited static and nonhuman data supporting the hypothesis that dysfunctional fat storage in subcutaneous adipose tissue contributes to obesity-associated insulin resistance,” the scientists wrote, adding that future identification of the molecules that cause this problem may help researchers develop drugs that could treat insulin resistance and prevent Type 2 diabetes.

Previously: The role of nutrition in diabetes prevention and management, Preventing pre-diabetes from turning into diabetes and The importance of regular exercise in delaying and treating diabetes
Photo by Kim P

Ask Stanford Med, Events, Nutrition, Obesity, Stanford News

Sticky situation: How sugar affects our health

Sticky situation: How sugar affects our health

132244825_dbf0e21d9f_zHere’s a shocking statistic: On average, Americans consume three pounds of sugar each week, or 3,550 pounds in an entire lifetime. This leads some to blame the sweet stuff for the increase of chronic disease in modern society. But simply reducing our sugar intake is easier said than done, in part because identifying foods with added sugars can be tricky.

This Thursday, Alison Ryan, a clinical dietician with Stanford Health Care, will deliver an in-depth talk on sugar and our health as part of a Stanford Health Library lecture series. Those unable to attend can watch the presentation online here.

In the following Q&A, Ryan discusses the controversies surrounding sugar and the role of sugar in our diet, and she offers tips for making sure your consumption doesn’t exceed daily guidelines.

Why does our body need sugar?

Sugar, in the form of dextrose or glucose, is the main fuel or energy source for the cells of the human body. Without glucose, our body has to get creative and rely on other metabolic pathways, like ketosis, to keep our brain and other organs running. There is an optimal range for our blood sugar levels, and our bodies are making constant efforts to keep blood sugar within this range.

Our body can make glucose from any carbohydrate that is consumed, so consuming monosaccharide (glucose and the like) is not biologically required. This is one of the reasons it’s difficult to determine the right amount of sugar that is required for the human body. Do we think of the optimal amount as the amount needed to function at peak level? Or an amount not to go over in order to avoid detrimental effects on our health?

Sugar intake has been on the rise in human diets. Why do you think that is?

At one time, sugar used to be a seldom available food item. It is now ubiquitous and more of a hallmark for highly processed, low nutritional value foods. Now, consider the food industry and the politics of sugar. Soda companies, makers of desserts, cakes, sugary snack foods, the sugar and corn syrup refiners all lobby to keep their products “part of a balanced diet.” The food industry is deeply involved (or at least vocal about) the food and nutrition guidelines in the U.S. Then there’s the reality that sugar tastes good! Most people enjoy the taste of sweet foods and are drawn to consuming them.

What are some of the health risks of consuming too much sugar?

Sugar has been implicated as playing a role in some obvious ways, like obesity, diabetes, and tooth decay; but also in less direct appearing ways such as heart disease, chronic inflammatory conditions, cancer, etc. Often, when we’re consuming foods high in sugar, we’re not consuming foods that are rich in nutrients. These calorie-dense foods displace the nutrient-dense foods. The net effect is higher intake of calories, with concurrent lower intake of vitamins, minerals, phytonutrients, protein, etc.

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Addiction, Obesity, Science, Videos

Discussing how obesity and addiction share common neurochemistry

Discussing how obesity and addiction share common neurochemistry

In a TEDMED talk published last week, renowned neuroscientist Nora Volkow, MD, discusses using insights from her research on drug addiction and brain chemistry to better understand the obesity epidemic.

Volkow, who directs the National Institute on Drug Abuse at the NIH, thought compulsive drug-taking behavior seemed remarkably similar to not being able to control what one eats. And indeed, with the help of PET scans that image living human brains, she found that the brain chemistry behind these two stigmatized problems is very similar.

The problem has to do with fewer dopamine D2 receptors; in her words, that’s “the biochemical signature of a brain where the capacity to control strong urges has been compromised.” She goes on to talk about such things as pleasurable stimuli versus conditioned stimuli, deprivation states, and how modern society could engineer environments that encourage health.

Volkow ends on a sociological note, challenging the moralizing idea that addiction and obesity indicate a failure to self-regulate:

Dismissal of addiction and obesity as just problems of self-control ignores the fact that for us to be able to exert self-control would require the proper function of the areas in our brains that regulate our behaviors… It’s like driving a car without brakes. No matter how much you want to stop, you will not be able to do it.

Previously: How eating motivated by pleasure affects the brain’s reward system and my fuel obesity; The brain’s control tower for pleasure; New tools from NIDA help diagnose and treat drug abuse

Nutrition, Obesity, Research, Stanford News

New insulin-decreasing hormone discovered, named for goddess of starvation

New insulin-decreasing hormone discovered, named for goddess of starvation

530468355_133d4da701_zLimos, the Greek goddess of starvation, must have relied on limostatin, the eponymous hormone recently discovered by Stanford researchers, to survive hunger.

She was clearly not well fed. As Ovid writes: “Her hair was coarse, her face sallow, her eyes sunken, her lips crusted and white; her throat scaly with scurf. Her parchment skin revealed the bowels within…”

Limostatin slashed her insulin levels, keeping nutrients in her blood so they could be used. Without limostatin, humans develop diabetes-like symptoms such as low blood sugar and a tendency toward obesity.

From our press release describing the Stanford work:

The researchers first discovered limostatin in fruit flies but then quickly identified a protein with a similar function in humans.

“Starvation or famine is an ancient, ever-present specter faced by all living organisms,” said Seung Kim, MD, PhD, professor of developmental biology. “The ways to deal with it metabolically are likely to be ancient and conserved. This research clearly connects the dots between flies and humans, and identifies a new potential way to regulate insulin output in humans.”

The researchers discovered limostatin by following a series of “biological breadcrumbs:”

Kim and his colleagues withheld food from their laboratory fruit flies for 24-28 hours and looked to see which genes were highly expressed during this time. They narrowed the list to those genes that encoded proteins resembling hormones, which are special signaling molecules that circulate throughout the body to affect the function of distant cells. They observed that one of these, limostatin, caused characteristics of insulin deficiency when overexpressed in flies…

Once the researchers had identified the receptor for limostatin in fruit flies, they looked to see if it resembled any human protein. A trail of biological breadcrumbs led them to the receptor for a protein called Neuromedin U. The protein is produced in the brain, and controls a variety of physiological responses including smooth muscle contraction, blood pressure control, appetite and hormone function in humans.

Based on their experiments in fruit flies, Kim and his colleagues expected that Neuromedin U might also be important in insulin regulation. They found that the protein is also expressed in the stomach and intestines, and the Neuromedin U receptor is found on insulin-producing beta cells in the pancreas. Neuromedin U and its receptor appeared to neatly connect nutrient sensing in the gut with insulin-producing cells elsewhere in the body.

Previously: Tiny fruit flies as powerful diabetes model, Beta cell development explored by Stanford researchers and Correspondence on the discovery of insulin
Photo by William Murphy

Biomed Bites, Cancer, Obesity, Research, Stanford News

Stanford researcher tackles tricky problem: How does a cell become a fat cell?

Stanford researcher tackles tricky problem: How does a cell become a fat cell?

Here’s this week’s Biomed Bites. Check each Thursday to meet more of Stanford’s most innovative biomedical researchers.

Mary Teruel had no intention of becoming a biology professor — after all, she was in a PhD program for aeronautical engineering. But the more she learned about cells, the more fascinated she became.

“I became very interested in the challenging problem of trying to understand the complex network in cells and trying to see if you could apply some of the principles from engineering to understand theses processes and make an insight into human disease,” Teruel says in the video above.

Teruel’s drive to investigate cells led her into her current role as an assistant professor of chemical and systems biology, where she’s striving to unravel a puzzle that underlies the obesity crisis in America: How do cells called pre-adipocytes (or pre-fat cells) become adipocytes (or adipocytes)?

By learning more about cell differentiation, Teruel’s research can also shed light on processes — and potential treatments — involved in cancer.

Learn more about Stanford Medicine’s Biomedical Innovation Initiative and about other faculty leaders who are driving biomedical innovation here.

Previously: Secrets of fat cells discovered, Fed Up: A documentary looks for answers about childhood obesity and How physicians address obesity may affect patients’ success in losing weight

Ask Stanford Med, Health and Fitness, Nutrition, Obesity

How to keep New Year’s resolutions to eat healthy

How to keep New Year's resolutions to eat healthy

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New Year’s Day always offers the opportunity to hit pause, reflect on our lives and set goals to improve our health and well-being. For many of us, this year also involved making promises to eat healthier and lose weight. To help you achieve your nutrition goals, I reached out to Stanford health educator Jae Berman. Below she shares how to select New Year’s resolutions that you’ll actually keep (perhaps you’ll have to tweak the ones you made last week!), offers strategies for eating healthy even when you’re pressed for time, and explains why cooking for yourself is a key factor in changing nutritional habits.

What are some examples of smaller, more manageable, goals that could help someone make better food choices?

People often jump in too hard, too fast when creating New Year’s resolutions. This perfectionist and “all or nothing” attitude tends to result in grand, lofty goals that we quit if we have a setback or don’t see immediate results. When considering health and weight loss-related goals make sure they are realistic and sustainable.

Instead, closely examine your routine and note one thing you can improve. This behavior may be something obvious, such as you drinking soda every day and wanting to stop. Or, it could be an aspiration to make healthy habits more sustainable, for example, bringing your lunch to work so you can lose weight and save money. Those who already eat well and exercise regularly may want to adopt a goal on a larger scope and learn to cook or try a new form of exercise.

Pick one thing (just one!) and make sure it is SMART – specific, measurable, achievable, results-focused and time-bound. Pick a resolution that is within reach, yet a bit of a stretch so that it’s a challenge. Additionally, goals should lead towards creating a sustainable habit. Some ideas include: Bring your lunch to work Monday-Thursday for the entire month of January; eat five fist-sized servings of vegetables every day; drink coffee only at breakfast; go to sleep at at the same time every night and wake up at the same time every morning for the month of January; or do 30 minutes of weight training three times a week.

In an effort to slim down in the New Year, some individuals may go on the Atkins diet and other popular weight-loss plans, or decide to do a juice fast, like the Master Cleanse. What’s your advice for those considering these approaches?

It’s very difficult to change someone’s mind when they decide to try these types of weight loss plans. So I usually say, “Go for it!” After a few days, the person often feels miserable and wants to create a long-term plan for managing their weight. I will say the one benefit of these quick fixes and fad diets, which I do not endorse, is that they teach a person what it feels like to be hungry. This may sound strange, but this awareness is an important lesson.

Many people overeat and are used to eating to avoid being hungry. We also tend to mindlessly eat out of boredom, or simply because food is in front of us. Going on a restrictive diet results in some feeling hungry for the first time in long time and, as a result they learn their hunger cues. When you experience a hunger cue, which is right when you think “I could eat,” then you should eat just enough food to get through the next three to four hours. You don’t need a huge meal to feel stuffed and small; unsatisfying snacks aren’t helpful either. Understanding what it feels like to be satiated is very important for long-term success.

Ongoing research at the Stanford Prevention Research Center shows that “one diet really does not fit all.”  So I can’t tell you exactly what to eat, but I can tell you that creating a long-term sustainable plan is key.

Continue Reading »

Chronic Disease, Nutrition, Obesity, Videos

The role of nutrition in diabetes prevention and management

The role of nutrition in diabetes prevention and management

Can certain diets help patients prevent or manage their diabetes? Which foods are best for diabetics and which ones should they avoid? If you increase your coffee consumption, will it reduce your risk of diabetes? Kathleen Kenny, MD, a clinical associate professor at Stanford, and Jessica Shipley, a clinical dietitian at Stanford Hospital & Clinics, answered these questions and others about diabetes and nutrition in a recent Stanford Health Library talk.

In the above video, Kenny and Shipley also discuss the glycemic index and how it should be used to tailor dietary choices; examine how Mediterranean, low-carb and low-calorie diets affect diabetes; and explain how eating healthy can prevent or reverse the disease. The lecture is a must-watch for anyone wanting to make healthier food choices to benefit their health.

This video is the final lecture in a three-part series addressing important questions related to diabetes and lifestyle choices.

Previously: Diabetes and nutrition: Healthy holiday eating tips, red meat and disease risk, and going vegetarian, Diabetes and nutrition: Why healthy eating is a key component of prevention and management, Diabetes self-management program helps at-risk teens and their families make healthier choices and New evidence for a direct sugar-to-diabetes link, Examining how diet soft drinks impact your health

Behavioral Science, Health and Fitness, Nutrition, Obesity, Public Health, Research

Perceptions about progress and setbacks may compromise success of New Year’s resolutions

3336185391_60148a87fa_zMy physical therapist is constantly telling me to pause during the workday and take stretch breaks to counter act the damage of being hunched over a computer for hours on end. After every visit to his office, I vow to follow his advice, but then life gets busy and before I know it I’ve forgotten to keep my promise.

So I decided that one of my New Year’s resolutions will be to set an alarm on my phone to serve as a reminder to perform simple stretches throughout the day. Keeping in mind that a mere eight percent of people who make resolutions are successful, I began looking for strategies help me accomplish my goal. My search turned up new research about how the perception of setbacks and progress influence achievement of behavior change. According to a University of Colorado, Boulder release:

New Year’s resolution-makers should beware of skewed perceptions. People tend to believe good behaviors are more beneficial in reaching goals than bad behaviors are in obstructing goals, according to a University of Colorado Boulder-led study.

A dieter, for instance, might think refraining from eating ice cream helps his weight-management goal more than eating ice cream hurts it, overestimating movement toward versus away from his target.

“Basically what our research shows is that people tend to accentuate the positive and downplay the negative when considering how they’re doing in terms of goal pursuit,” said Margaret C. Campbell, lead author of the paper — published online in the Journal of Consumer Research — and professor of marketing at CU-Boulder’s Leeds School of Business.

Given these findings, researchers suggest you develop an objective method for measuring your progress and monitor it regularly.

Previously: Resolutions for the New Year and beyond, How learning weight-maintenance skills first can help you achieve New Year’s weight-loss goals, To be healthier in the new year, resolve to be more social and Helping make New Year’s resolutions stick
Photo by Laura Taylor

Nutrition, Obesity, Stanford News, Videos

Easy-to-follow tips to avoid overeating this holiday

Easy-to-follow tips to avoid overeating this holiday

‘Tis the season for overindulging. A recent report showed that we can easily consume 2,000 calories (or more) during a holiday dinner, particularly if the celebration includes appetizers and a few glasses of wine. As Neha Shah, a registered dietitian at Stanford, explains in the above Stanford Health Care video, overeating during this time of year is tied to many factors. She says, “There is so much food available at one given social setting that it’s easy to overeat and not realize it.”

There are simple techniques, however, that can help you resist the temptation to pile your plate high and go back for seconds. Watch the full video to learn easy-to-follow tips for making healthier choices this holiday season as you eat, drink and be merry.

Previously: “Less is more:” Eating wisely, with delight, during the holidays, Eat well, be well and enjoy (a little) candy, Learning tools for mindful eating and Enjoying the turkey while watching your waistline
Photo in featured-entry box by George Redgrave

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