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Cancer, In the News, Nutrition, Patient Care, Surgery

“Prehab” routines before cancer surgery help patients bounce back faster

Surgery_flickr_thinkpanamaIf you’ve ever had surgery, especially an orthopedic one, you’ve probably had rehabilitation therapy. In recent years, orthopedic surgery plans have begun to include a period of “prehabilitation” exercise to help prepare patients for their procedure. Now, researchers have demonstrated that a pre-surgery work-out routine combined with some dietary changes may be able to help cancer patients regain their baseline strength levels sooner. A story on NPR’s Shots blog described the recent study:

Researchers from McGill University in Montreal studied 77 patients scheduled for colorectal cancer surgery. A kinesiologist gave the patients aerobic exercises and strength training to do at home. A registered dietitian gave them nutritional counseling and prescribed a whey supplement to make up any protein deficits, and a psychologist provided anxiety-reducing relaxation exercises.

Half of the patients were told to start the program before surgery – an average of about 25 days before – and to continue afterward for eight weeks. The other group was told to start right after surgery.

Not surprisingly, the group assigned to prehabilitation did better on a presurgery test that measured how far they could walk in 6 minutes. And it paid off.

Two months after surgery, the prehabilitation group walked an average of 23.7 meters farther than when they started the study. Rehab-only patients walked an average of 21.8 meters less than when they started. (A change of 20 meters is considered clinically significant.) And a greater proportion of the prehabilitation group was back to baseline exercise capacity by then.

Because of the methology the researchers used, it’s not clear how the diet or the exercise prescribed in the pre-surgery regimen affected the outcome. Previous studies that looked at exercise-only regimens did not show post-surgery improvements. A larger study with a more varied pool of patients is likely needed for definitive answers.

Previously: Wellness after cancer: Stanford opens clinic to address survivors’ needs and A call for rehab services for cancer survivors
Photo by thinkpanama

Health and Fitness, Nutrition

Eat well, be well and enjoy (a little) candy

Eat well, be well and enjoy (a little) candy

260823789_3eda4b0439_oAs Halloween treats fill cupboards, jack-’o-lanterns and workplace counters, I bet you’re hunting for a middle ground between candy glutton and candy curmudgeon. Anticipating this tricky balance, Stanford dieticians Rosalyne Tu, MS, RD and Raymond Palko, MS, RD, offered some healthy eating tips in this BeWell@Stanford feature:

What are some common pitfalls during the holidays that can contribute to weight gain?

RP: Often, the concept of “moderation” can undermine our good intentions. Moderate eating does not mean consuming two pieces of pumpkin pie instead of three. Rather, it means having a small slice of pie, one or two times over the course of a week.

RT: Sometimes we are too “good” about budgeting our calories and we skip meals or under-eat during the day to save up calories for large holiday meals. This strategy can backfire on us because our appetite hormones get very strong and we end up in less control of our appetites, causing us to overeat later. Our bodies were designed to treat starvation as our worst enemy; therefore, when we are hungry, we naturally crave highly caloric foods (high sugar and fat). For some people, giving in to these foods brings on feelings of guilt when the biological response was natural.

RP: Increased alcohol consumption is another road bump. At parties, alcohol can flow freely, and it is very calorically dense without any nutritional benefits.

RT: Liquid calories are often empty calories. Alcohol, specifically, can promote overeating because of its ability to break down willpower while causing blood sugars to drop — both of which could encourage overeating.

But it’s still possible to enjoy your favorite treats, the two dieticians said:

RT: Food is meant to be enjoyed! Give yourself permission to enjoy your favorite treat and practice eating mindfully. Eat your treat like it is a fine dining experience: slow down, savor every morsel, and minimize the distractions like the television and computer. Eating mindfully helps your body decide how much it is truly hungry for.

Previously: When it comes to weight loss, maintaining a diet is more important than diet type, Where is the love? A discussion of nutrition, health and repairing our relationship with food and How to avoid a candy-coated Halloween
Photo by Juushika Redgrave

Applied Biotechnology, Genetics, In the News, Nutrition, Public Health, Research

“Frankenfoods” just like natural counterparts, health-wise (at least if you’re a farm animal)

"Frankenfoods" just like natural counterparts, health-wise (at least if you're a farm animal)

cow2More than a hundred billion farm animals have voted with their feet (or their hoofs, as the case may be). And the returns are in: Genetically modified meals are causing them zero health problems.

Many a word has been spilled in connection with the scientific investigation of crops variously referred to as “transgenic,” “bioengineered,” “genetically engineered” or “genetically modified.” In every case, what’s being referred to is an otherwise ordinary fruit, vegetable, or fiber source into which genetic material from a foreign species has been inserted for the purpose of making that crop, say, sturdier or  more drought- or herbicide- or pest-resistant.

Derided as “Frankenfoods” by critics, these crops have been accused of everything from being responsible for a very real global uptick in allergic diseases to causing cancer and autoimmune disease. But (flying in the face of the first accusation) allergic disorders are also rising in Europe, where genetically modified, or GM, crops’ usage is far less widespread than in North America. It’s the same story with autoimmune disease. And claims of a link between genetically modified crops and tumor formation have been backed by scant if any evidence; one paper making such a claim  got all the way through peer review and received a fair amount of Internet buzz before it was ignominiously retracted last year.

But a huge natural experiment to test GM crops’ safety has been underway for some time. Globally, between 70 and 90 percent of all GM foods are consumed by domesticated animals grown by farmers and ranchers. More than 95 percent of such animals – close to 10 billion of them – in the United States alone consume feed containing GM  components.

This was, of course, not the case before the advent of commercially available GM feeds in the 1990s. And U.S. law has long required scrupulous record-keeping concerning the health of animals grown for food production. This makes possible a before-and-after comparison.

In a just-published article in the Journal of Animal Science, University of California-Davis scientists performed a massive review of data available on performance and health of animals consuming feed containing GM ingredients and  products derived from them. The researchers conclude that there’s no evidence of GM products exerting negative health effects on livestock. From the study’s abstract:

Numerous experimental studies have consistently revealed that the performance and health of GE-fed animals are comparable with those fed [otherwise identical] non-[GM] crop lines. Data on livestock productivity and health were collated from publicly available sources from 1983, before the introduction of [GM] crops in 1996, and subsequently through 2011, a period with high levels of predominately [GM] animal feed. These field data sets representing over 100 billion animals following the introduction of [GM]crops did not reveal unfavorable or perturbed trends in livestock health and productivity. No study has revealed any differences in the nutritional profile of animal products derived from[GM]-fed animals.

In other words, the 100 billion GM-fed animals didn’t get sick any more frequently, or in different ways. No noticeable difference at all.

Should that surprise us? We humans are, in fact, pretty transgenic ourselves. About 5 percent of our own DNA can be traced to viruses who deposited their  genes in our genomes, leaving them behind as reminders of the viral visitations. I suppose that’s a great case against cannibalism if you fear GM foods. But I can think of other far more valid arguments to be made along those lines.

Previously: Ask Stanford Medicine: Pediatric immunologist answers your questions about food allergy research, Research shows little evidence that organic foods are more nutritional than conventional ones and Stanford study on the health benefits of organic food: What people are saying
Photo by David B. Gleason

Health and Fitness, Nutrition, Pediatrics, Public Health

Pediatrics group issues new recommendations for building strong bones in kids

Pediatrics group issues new recommendations for building strong bones in kids

MilkshelfOur bones function as retirement-savings accounts for calcium: We deposit the mineral into our bones when we’re young, then draw on the stores as we age. Too little calcium in the “savings account” puts people at risk for osteoporosis and debilitating bone fractures later in life.

This means that, although osteoporosis is usually seen as a disease of old age, pediatricians and parents need to pay attention to bone health. This week, the American Academy of Pediatrics released updated guidelines for pediatricians on how nutrition and exercise can improve bone density in their patients. The guidelines were co-authored by Stanford’s Neville Golden, MD, who is also an adolescent medicine specialist at Lucile Packard Children’s Hospital Stanford. The report discusses calcium, which strengthens bones; vitamin D, which helps the body absorb calcium; and weight-bearing exercise, which promotes calcium deposition into the bones.

In addition to protecting against fractures in old age, the guidelines address the needs of kids whose bones are weakened by a variety of childhood and adolescent medical conditions, including juvenile osteoporosis, cystic fibrosis, lupus, celiac disease, cerebral palsy and anorexia nervosa.

A few highlights from the recommendations:

  • Children and adolescents should get their calcium mostly from food, not supplements. To meet calcium requirements, the committee recommends three or four daily servings of dairy foods (depending on the child’s age) and also suggests alternative food sources such as dark green veggies, beans, and calcium-fortified orange juice or breakfast cereals.
  • Vitamin D recommendations went up in 2011; the AAP agrees with the increased recommendations for all children and notes that kids using certain medications have even higher requirements than healthy children. Although the body can make vitamin D from sunlight, the report notes that kids are spending more time indoors and that sunscreen prevents vitamin D synthesis, making children more reliant on food and supplements to get enough vitamin D.
  • Soda often displaces milk in children’s diets, adding bone health to the list of reasons doctors should discourage soda consumption.
  • Weight-bearing exercise helps strengthen the bones. The report recommends activities such as walking, jogging, jumping and dancing over exercises such as swimming and cycling for building bone health.
  • Adolescent girls with eating disorders such as anorexia nervosa and the female athlete triad experience bone loss. In the past, some physicians have suggested that these young women could improve their bone density by taking oral contraceptives, but the report notes that randomized controlled trials have not found any evidence that oral contraceptives increase bone mass for these patients.

Previously: Goo inside bones provides structural support, study finds, New genetic regions associated with osteoporosis and bone fracture and Avoiding sun exposure may lead to vitamin D deficiency in Caucasians
Photo by Stephanie Booth

Nutrition, Obesity, Research, Stanford News

When it comes to weight loss, maintaining a diet is more important than diet type

When it comes to weight loss, maintaining a diet is more important than diet type

bathroom_scaleSelecting a weight-loss plan can be tricky. Everywhere you look, media reports bombard you with stories about how Jennifer Hudson lost 80 pounds by joining Weight Watchers, Sharon Osbourne shed 23 pounds on the Atkins diet, and other A-listers slimmed down on the Zone Diet. And then there’s that close friend who dropped three dress sizes after following the South Beach Diet. How do you determine which dieting plan is the most effective?

To answer this question, Edward Mills, PhD, a visiting associate professor at Stanford, and colleagues completed a network meta-analysis of 48 randomized trials of brand-name diets, which included a total of more than 7,200 overweight or obese adults. In addition to those mentioned above, researchers also evaluated six other diets: Ornish, Vulumetrics, Jenny Craig, Rosemary Conley, Biggest Loser and Nutrisystem. The diets were divided into three categories —  low-carb, low-fat and moderate macronutrient.

The diet that a person can maintain for the long term, or for as long as possible, is the most effective weight-loss plan

Overall, the study showed that if people stuck to their diets (no matter the type) they lost weight, but ultimately the “weight-loss differences between individual diets were minimal and largely unimportant,” according to Mills. The study authors concluded that the diet that a person can maintain for the long term, or for as long as possible, is the most effective weight-loss plan. They also found that exercise and behavioral support can enhanced weight loss.

Interested to know more about the research, I reached out to Mills, who explained how the evidence failed to support recommending a specific diet and discussed the potential of being able to combine diets to achieve lasting weight loss without having to maintain strict eating habits.

Why did you and your colleagues complete a comparison study of popular diets?

There is a massive weight-loss industry that promotes different diets that are marketed in different ways. Some diets are promoted as being more medical, such as the Ornish diet, while others target people according to lifestyle, for example the South Beach diet. With all the promotion of different diets occurring and people discussing what they believe works or does not work, we wanted to examine whether the clinical trial evidence demonstrated superiority of any particular diet, a strategy we are calling “evidence-based dieting.”

In the study, individuals on a low-carb and low-fat diet lost the most weight (8 kg over six months), compared to those who were not on any diet. Why are these diets not considered to be the most effective of those studied?

These diets do appear to offer the largest weight-loss benefits, but the difference between the different diets was so small that other issues begin to be more important. We looked at the diets using two different analyses. First, we grouped diets according to their type of diet, called a class, and then examined whether the individual diet resulted in different outcomes. Although we found differences according to the classes of diets, these were not really observed when we examined the individual diets. So at this point, we can’t recommend any particular diet over another. But those that are low carb or low fat are preferable.

What did you find most surprising about the study results?

What is most surprising about the results is that the individual diet a person chooses doesn’t seem to be the most important aspect of dieting, instead maintaining a diet is. Some people have a lot of difficulty adhering to a diet because they find the particular diet too difficult to maintain, such as avoiding carbs if they’re trying the Atkin’s diet. It appears that if all diets offer more or less the same benefits, then people should be able to switch between diets when they need to. This approach may be really helpful in adhering to dieting in general.

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Mental Health, Nutrition, Obesity, Research, Women's Health

Stressed? You could be burning fewer calories

Stressed? You could be burning fewer calories

cupcakesBad news, ladies: Findings (subscription required) recently published in Biological Psychiatry show that women who consumed comfort food while feeling stressed burned fewer calories than their zen-like counterparts.

In the study, Ohio State University researchers quizzed a group of women about what was causing stress in their lives before they ate a caloric meal consisting of eggs, turkey sausage, biscuits and gravy. Scientific American reports:

Turns out that the most stressed women had higher levels of insulin. Which slows down metabolism and causes the body to store fat. And that fat, if not burned off, accumulates in the body.

The women who had reported feeling stressed or depressed in the day before eating the meal burned 104 fewer calories during the seven hours following the meal than women who felt more mellow.

If eating high-calorie comfort food to alleviate stress becomes habitual, the result could be an average weight gain of 11 pounds per year.

So next time you’re feeling overwhelmed and exhausted, you might want to reconsider reaching for a cupcake.

Previously: Learning tools for mindful eating, Mindful eating tips for the desk-bound and Want to curb junk food cravings? Get more sleep
Photo by Class V

Autoimmune Disease, Evolution, Immunology, Microbiology, Nutrition, Public Health, Stanford News

Civilization and its dietary (dis)contents: Do modern diets starve our gut-microbial community?

Civilization and its dietary (dis)contents: Do modern diets starve our gut-microbial community?

hunter-gatherer cafe

Our genes have evolved a bit over the last 50,000 years of human evolution, but our diets have evolved a lot. That’s because civilization has transitioned from a hunter-gatherer lifestyle to an agrarian and, more recently and incompletely, to an industrialized one. These days, many of us are living in an information-intensive, symbol-analyzing, button-pushing, fast-food-munching society. This transformation has been accompanied by consequential twists and turns regarding what we eat, and how and when we eat it.

Toss in antibiotics, sedentary lifestyles, and massive improvements in public sanitation and personal hygiene, and now you’re talking about serious shake-ups in how many and which microbes we get exposed to – and how many of which ones wind up inhabiting our gut.

In a review published in Cell Metabolism, Stanford married-microbiologist couple Justin Sonnenburg, PhD, and Erica Sonnenburg, PhD, warn that modern civilization and its dietary contents may be putting our microbial gut communities, and our health, at risk.

[S]tudies in recent years have implicated [dysfunctional gut-bug communities] in a growing list of Western diseases, such as metabolic syndrome, inflammatory bowel disease, and cancer. … The major dietary shifts occurring between the hunter-gatherer lifestyle, early Neolithic farming, and more recently during the Industrial Revolution are reflected in changes in microbial membership within dental tartar of European skeletons throughout these periods. … Traditional societies typically have much lower rates of Western diseases.

Every healthy human harbors an interactive internal ecosystem consisting of something like 1,000 species of intestinal microbes.  As individuals, these resident Lilliputians may be tiny, but what they lack in size they make up in number. Down in the lower part of your large intestine dwell tens of trillions of  single-celled creatures – a good 10 of them for every one of yours. If you could put them all on a scale, they would cumulatively weigh about four pounds. (Your brain weighs three.)

Together they do great things. In a Stanford Medicine article I wrote a few years back, “Caution: Do Not Debug,” I wrote:

The communities of micro-organisms lining or swimming around in our body cavities … work hard for their living. They synthesize biomolecules that manipulate us in ways that are helpful to both them and us. They produce vitamins, repel pathogens, trigger key aspects of our physiological development, educate our immune system, help us digest our food and for the most part get along so well with us and with one other that we forget they’re there.

But when our internal microbes don’t get enough of the right complex carbohydrates (ones we can’t digest and so pass along to our neighbors downstairs), they may be forced to subsist on the fleece of long carbohydrate chains (some call it “mucus”)  lining and guarding the intestinal wall. Weakening that barrier could encourage inflammation.

The Sonnenburgs note that certain types of fatty substances are overwhelmingly the product of carbohydrate fermentation by gut microbes. These substances have been shown to exert numerous anti-inflammatory effects in the body, possibly protecting against asthma and eczema: two allergic conditions whose incidence has soared in developed countries and seems oddly correlated with the degree to which the environment a child grows up in is spotlessly hygienic.

Previously: Joyride: Brief post-antibiotic sugar spike gives pathogens a lift, The future of probiotics and Researchers manipulate microbes in the gut
Photo by geraldbrazell

In the News, Nutrition, Research

How much caffeine is really in one cup of coffee?

How much caffeine is really in one cup of coffee?

coffee_beansPrevious research has shown that regularly drinking coffee could offer a number of health benefits, including reducing prostate cancer risk, improving symptoms related to Parkinson’s disease, staving off the development of Alzheimer’s, decreasing diabetes risk and providing antioxidants.

But too much caffeine can make you jittery, disrupt your sleep and, potentially, shorten your life span. So it’s often recommended that you drink coffee in moderation, which is defined as two or three eight-ounce cups of brewed or drip coffee.

The problem with recommending a certain number of cups, reports Scientific American, is that new research shows the caffeine and caffeoylquinic acid (CQA) content can vary greatly depending on the type and preparation of the coffee. From the piece:

Results showed that the caffeine-to-CQA ratio in espressos ranged from 0.7–11, depending on the preparation conditions. With serving volumes from 13–104ml, it’s no wonder that Crozier says ‘cup of coffee is an exceedingly variable unit. To estimate health benefits using cups may be very difficult,’ – and inadvisable in epidemiological studies.

But what are CQAs? Beans contain various (poly)phenols, including 3-, 4- and 5-O-caffeoylquinic acids, the main phenolic compounds in coffee. Epidemiological studies have suggested the link between the lower risk of type 2 diabetes, cardiovascular diseases, and endometrial and hepatocellular cancer in habitual coffee consumers might be due to the presence of CQAs in coffee. They sound like super-compounds, but that’s a big ‘might’, and research continues.

Whilst the biological effects of CQAs are uncertain, one thing we do know about them is they are more sensitive to roasting than caffeine. The bean or blend also affects the caffeine-to-CQA ratio. Arabica and Robusta are the most common bean types and the latter contains twice as much caffeine as the former.

The article highlights the need to better inform consumers about the actual amount of caffeine in coffee and the need for more research on the health benefits of coffee.

Previously: How the body’s natural defenses help protect cells from toxins in everyday foods and flavorings, What is coffee?, For new moms, coffee scores a point: Caffeine doesn’t seem to interfere with baby’s sleep in study and Does coffee lower the risk of prostate cancer?
Photo by Nina Matthews

Global Health, Nutrition, Research, Stanford News

Stanford researchers address hunger in new book on food security

Stanford researchers address hunger in new book on food security

riceA piece from Stanford’s Freeman Spogli Institute for International Studies notes how experts across campus are working together to address the complex global problem of hunger. A new book, The Evolving Sphere of Food Security (Oxford University Press, August), discusses the problem from numerous perspectives, including medicine, in its 14 chapters. The book’s editor, Rosamond Naylor, PhD, is director of the Center on Food Security and the Environment, which is housed jointly within the FSI and the Woods Institute for the Environment.

From the piece:

“This book grew out of a recognition by Stanford scholars that food security is tied to security of many other kinds,” said Naylor, who is also William Wrigley Senior Fellow at the Freeman Spogli Institute for International Studies and the Stanford Woods Institute for the Environment. “Food security has clear connections with energy, water, health, the environment and national security, and you can’t tackle just one of those pieces.”

Stanford has a long history of fostering cross-disciplinary work on global issues. It is in this spirit that the idea for the book was born, Naylor said. The book weaves together the expertise of authors from the fields of medicine, political science, engineering, law, economics and climate science.

A recurring theme throughout the book – also reflected in its title – is the evolving nature of the food security challenges countries face as they move through stages of economic growth. At low levels of development, countries struggle to meet people’s basic needs. For example, Naylor’s chapter on health, co-authored with Eran Bendavid [MD] (medicine), Jenna Davis [PhD] and Amy Pickering [PhD] (civil and environmental engineering), describes a recent study showing that poor nutrition and rampant disease in rural Kenya is closely tied to contaminated, untreated drinking water. Addressing these essential health and sanitation issues is a key first step toward food security for the poorest countries.

Previously: Seeking solutions to childhood anemia in ChinaWho’s hungry? You can’t tell by lookingCould a palm oil tax lower the death rate from cardiovascular disease in India? and Foreign health care aid delivers the good
Photo by Thomas Wanhoff

CDC, Nutrition, Pediatrics, Public Safety, Research, Stanford News

“Happy Meal ban”: Where are we now?

"Happy Meal ban": Where are we now?

MuppetBabiesA newly released Centers for Disease Control report of a study conducted at Stanford has examined the effects of San Francisco’s 2010 “Happy Meal ban.” The ban prohibited the free distribution of toys with unhealthy meals; the fast-food restaurants McDonald’s and Burger King instead sold the toys for 10 cents. Though neither restaurant complied with the ordinance’s specific calls for changes in nutritional content, improvements have been made.

As reported by SFGate.com:

…over the study’s two-year period, McDonald’s in particular made big changes to its Happy Meals, said [Jennifer Otten, MD,] of the University of Washington School of Public Health — first in California, then nationally.

The fast food giant cut the amount of French fries it serves in Happy Meals in half, replacing them with apples; stopped serving caramel sauce with apples; and began offering nonfat chocolate milk to customers. Otten said those substitutions were “pretty dramatic,” — they reduced the calories in a Happy Meal by 110, and cut the sodium and fat content of the meal as well.

Otten and her colleagues, including senior author Abby King, PhD, concluded in the study, “Although the changes…  did not appear to be directly in response to the ordinance, the transition to a more healthful beverage and default side dish was consistent with the intent of the ordinance. Study results… suggest that public policies may contribute to positive restaurant changes.”

Previously: How fast-food restaurants respond to limits on free toys with kids’ meals, Toying with Happy Meals, How food advertising and parents’ influence affect children’s nutritional choices and Living near fast food restaurants influences California teens’ eating habits
Photo by Ursala Urdbeer

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