Author: Staci

Navigating IBS with FODMAPs

stomach-ache

Irritable Bowel Syndrome (IBS) is fairly common medical diagnosis that a registered dietitian will encounter. Twenty percent of the North American population suffers from IBS and as many as two-thirds of patients report specific food triggers which subsequently leads to food restriction. Though diet does not cause IBS, it can be optimized to improve symptoms and patient quality of life.

One of the strategies to combat IBS symptoms is a diet low in particular classes of carbohydrates: fermentable oligosaccharides, disaccharides, monosaccharides and polyols (sugar alcohols) (FODMAPs). In patients with IBS, these carbohydrates are poorly absorbed and are rapidly fermented by GI bacteria. The fermentation process leads to increased water and gas in the small intestine—which results in the uncomfortable symptoms of IBS. A low FODMAP diet is characterized by a reduction in wheat, elimination of lactose and low in disproportionate fructose. The diet appears to effectively control symptoms in ~50-70% of patients with IBS.

FODMAP containing foods are everywhere in an American diet. Wheat, artichokes, chicory root (the fiber added to many foods with “added fiber”) and garlic contain FODMAPs. Even healthy foods can be less-than-ideal for IBS patients; honey, apples, pears, watermelon, mushrooms, onions and cauliflower can be extremely irritating to the stomachs of IBS patients. Though the mechanisms of altered absorption are different per subtype of carbohydrate, the effects from each type are cumulative in the gut. For example, a high fiber cereal for breakfast, a salad with onions for lunch and pasta for dinner all contribute FODMAPs; the cumulative effect over a patient-specific threshold can result in symptoms.

What is even more interesting with FODMAPs is their symptoms are subclass-specific. A patient experiences gas or diarrhea, it is likely from fructan consumption, which affects the sigmoid colon. Conversely, fructose is an irritant to the small intestine which can lead to constipation or pain. An RD can piece together a patients diet with their GI symptoms and tailor a diet very specific to their needs. Thus, the RD plays an essential role in the management of IBS symptoms. With each patient, practitioners need to conduct detailed dietary recalls and identify the foods that contain FODMAPs and work with the patient to optimize their nutrition plan.

Nee J, Scarlata K. Using Science to Further Define FODMAPs and Simplify Patient Education. Food and Nutrition Conference and Expo 2016. Date: October 17, 2016

 

Taste vs. experience: Bariatric surgery and food preferences

Bariatric surgery is an appealing weight loss option for many Americans for whom diet and exercise has not been an effective means of weight loss. The Roux en Y gastric bypass surgical procedure creates a very small pouch out of the stomach and reconnects this new pouch to a latter portion of the intestine. This limits the contact food has with absorptive tissues in the intestine as well as severely limiting the portion of food patients can consume at one time.

Anecdotally, patients report a decreased preference for sweet tasting and fatty foods after their surgery. Alan Spector, PhD, from Florida State University, hopes his research can help to identify a mechanism behind this phenomenon in an animal model. His work is part of a translational research project which will ultimately integrate human research being conducted in Ireland with his results in an animal model.

Dr. Spector designed a study that analyzed food intake of rats before and after bariatric surgery. The rats were familiarized with five food items with specific macronutrient compositions before surgery: refried beans (low sugar, low fat), low fat yogurt (low fat, high sugar), creamy peanut butter (high fat, low sugar), and sugar fat “whip” (high fat, high sugar). After a healing period where post-surgery weight loss and healing occurred, the intervention began.

On the first day of the reintroduction of the different food groups, the proportions of macronutrient intake between the gastric bypass rats and controls were the same. However, as days passed, rats with gastric bypass decreased their proportion of fat intake significantly compared to control animals. Fat intake was replaced by carbohydrate and protein but it is important to note that intake from “added sugars” remained constant–implying the majority of the changes came from increasing refried bean consumption and decreasing sugar whip intake. Importantly, the change happened over time, and considering this, Dr. Spector theorizes that change in intake is taking place due to the experiences of the rats, rather their their taste preferences specifically (1).

These findings set the stage for exciting research in the future in the path to identify the mechanisms behind what is causing the behavior change anecdotally observed in humans. However, it is extremely interesting to see the observed human behavior change in rats, and implies there is a mechanism to be identified. Practitioners, especially Registered Dietitians, can benefit from this information. Many patients, because of insurance purposes, must go through intensive lifestyle counseling before and after surgery. Informing patients of the changes they will experience is crucial. Though Dr. Spector’s research doesn’t say with certainty what changes in the body may be driving taste preferences, his research does support what observational data has already concluded. Counseling on issues such as dumping syndrome as well as food preference changes can prepare patients for what to expect after such a life changing procedure.

  1. Alan Spector. Taste, Palatability, Food Selection and Gastric Bypass. University of Georgia. Department of Foods and Nutrition Seminar Series. October 5, 2016.

Eating in moderation can mean three cookies, or six.

cookieA popular phrase among some registered dietitians (RD) is “Anything is healthy in moderation.” Though other RD’s will roll their eyes at that idea and softly mutter under their breath “A small portion doesn’t mean it provides optimal nutrition”, Dr. VanDellen has some research to debunk the ‘moderation myth’. Dr. VanDellen is a researcher in the Psychology department at the University of Georgia and studies how people can be successful at self-regulation and self-control1. Self-regulation and self-control are words often tossed around in the context of obesity research and understanding how people’s interpretations of moderate amounts of food can help understand their behavior.

Dr. VanDellen explained that “moderation” can take on different meanings, depending on when you ask questions related to moderation.2 She went on to explain that the following two questions should have the same answer if a person is truly “eating in moderation”:

  1. “How many cookies should you eat?”
  2. “How many cookies would be considered ‘a moderate amount’?”

The results were conflicting; the answer to question (1) was “2” and the answer to question (2) was “3”. She went on to explain that, for her participants, “moderate consumption” was consistently reported as a greater amount than what they actually consumed, if they were prompted with the question after they ate the cookies. Additionally, if you asked them question (2) before they ate the cookies, the reported moderate” amount wasn’t as consistent across participants, but it was always more than what they ended up eating as the intervention time progressed.

The perceptions of moderation justified their actions—but their perceptions changed based on their scenario. Consistently with this, if more food was consumed during the study period, the more food subjects perceived they could eat it while still considering it “in moderation”. In a computer-simulated “Thanksgiving meal”, VanDellen compared participants who were told to either build their Thanksgiving plate as they would on the actual holiday, or to construct a plate “in moderation”. In the latter scenario, they put more food on their plates!

Her take home message? Moderation messages are not reducing the number of calories people are consuming!

These findings present an interesting new construct for healthcare practitioners, especially RDs, to consider. According to Dr. VanDellen’s research, participants consume more food when they are told to eat foods in moderation and the definition of moderation depends on when people are prompted with the question. From the evidence she presented, “moderation” is too abstract a concept to facilitate beneficial behavior change, especially if weight loss is the primary desirable outcome. A better option would be to teach people how to identify the amount of calories, fat and added sugars are found in specific foods, and providing them with the tools to assess how these foods can fit within their daily (or weekly) intakes.

  1. Michelle VanDellen. University of Georgia. Internet: http://psychology.uga.edu/directory/michelle-vandellen. Accessed 21 September 2015.
  2. Michelle VanDellen. Counterintuitive Finding in How Nutrition and Health Messages Affect Consumption. University of Georgia. Department of Foods and Nutrition Seminar Series. October 7, 2015.

Drink EtOH? Breathe out extra CO2 to reduce cancer risk

 

CNN recently claimed gym go-er’s can exercise off the negative health risks associated with alcohol—but it has left scientists rolling their eyes at the weight rack. The article took its presumptuous turn when the conclusion from an observational study was “exercising the recommended amount “cancels out” the higher risk of cancer death brought about by drinking”. By the sheer nature of an observational study, it is scientifically impossible to make a statement of this magnitude. Though physical activity attenuates the risk of cancer, a closer analysis of the study design raises some points of concern that could be influencing the results.

It is extremely important to analyze how participants were characterized for analysis; the following table demonstrates researchers organization scheme. Physical activity was collected from self-report data which was validated against accelerometers (the “gold standard”). However, it was only validated in the English cohort, not the Scottish cohort. Considering the conclusions were based on survey data, readers need to be mindful of how inaccurate self-reporting can be. The different categories of alcohol consumption were also collected from self-report data, which may not be wholly accurate, especially at the two extremes of rare or excessive alcohol intake. An important limitation of the article is the lack of analysis regarding the patterns of alcohol consumption. Researchers noted a health difference between binge drinking and other drinking patterns—this was not mentioned on CNN.

 

Categories of Alcohol Intake

Physical activity categories

1. Never drunk Inactive (<7 MET*-hour/wk)

* MET = Metabolic equivalent

2. Ex-drinkers
3. Occasional drinkersActive lower (>7.5 MET-hr/wk)
4. Within guidelines (<14 W, <21 M)
5. Hazardous (14-35 W, 21-49 M)Active upper ( >15 MET-hr/wk)
6. Harmful (>35 W, >49 M)

A statement omitted in the CNN piece is very important for critical analysis of the results, “our results confirmed that the inclusion of former drinkers in the reference group…has the potential to overestimate the protective effects of drinking at the recommended level.” Taking a closer look at this reference group reveals the potential limitations. “Never drinkers” reported the lowest amount of PA and were older than the “hazardous” drinkers. The chronic disease and CVD rates were higher in this group as compared to “hazardous” drinkers, as well. Though researchers controlled for these variables, the statistical limitations of the more severe characteristics of this reference group is notable. reported 1.6 hr/wk of PA, they were, on average, 60 years old with a BMI of 26.7. Many (57.3%) reported a long standing illness and 12.1% reported a diagnosis of CVD. On the other hand, “hazardous” drinkers interestingly had the highest levels of PA of any group (6.3 hours per week). They were much younger (53), with a similar BMI (26.5). Their rates of chronic illness and CVD were also lower (46% and 6.9%, respectively). These variables were controlled for in the statistical analysis, however, the baseline participants from which others were compared had a very different health profile.

Finally, these data were collected at baseline and may not be representative of long-term behaviors of the participants. Furthermore, researchers did not analyze dietary habits at all, which largely contribute to the environmental risk associated with cancer. The limitations discussed here are fairly common in this type of research; observational data is plagued by limitations due to study design. However, when research scientists analyze the data, they understand this. Identifying such concrete conclusions from observational data is reckless on the part of CNN, and likely the article was approved because of the traffic it would bring to the site.

Ultimately, for the average consumer, the message media sources need to be sending is that exercise is healthy, no matter which health outcome you statistically manipulate to tell your story. Articles such as this try to tease out the mechanisms of the benefits, when really, the focus should be articles that teach people how to implement the behaviors. Taking alcohol as the example, an article teaching ways to choose exercise over alcohol drinking a couple nights a week would be great! That type of article would be directed at the root cause a population is not exercising (lack of time) and creating a solution for their barrier–inspiring more change than this “click bait” article ever could.

Is Apple Juice the New Coffee?

coffee

Coffee is the choice elixir of night owls, professionals, new moms and the sleep deprived alike. For some, it’s the sound of the bubbling water, for others it’s the aromatic, earthy smell that creeps through their morning-lit kitchens. Many will agree, though, that the appeal is the jolt of energy that quickly follows their morning cup of joe—thank you, caffeine.

Caffeine, found in coffee, energy drinks, soda and even chocolate, stimulates neurotransmission in the central nervous system (the noggin) to prevent the onset of drowsiness. This increase in communication between areas in the brain results in the caffeine “buzz” associated with coffee. However, an additional effect of caffeine is a narrowing of the blood vessels in the brain, causing a reduction in blood flow. This decrease in blood flow is an undesirable effect because adequate blood flow is associated with better brain function. Researchers hypothesize that coupling the stimulatory effects of caffeine with a strategy to increase blood flow will result in greater cognitive function. Dr. O’Connor at the University of Georgia aimed to test the effects of the brain stimulatory effect of caffeine coupled with the vessel dilating effects of polyphenols in apple juice1.

The experiment included placebo drinks, a caffeine control and apple juice “caffeine cocktails” with varying levels of caffeine. Researchers investigated their effects on motivation, sustained attention and reaction time. In the lab, participant’s tasks were quite tedious number identification exercises, but in a real life scenario, these measurements can translate to:

  • Desire/motivation to buckle down and get to work
  • How long focus can be maintained and accuracy of the work completed
  • How quickly work is performed

His experiments revealed that apple juice with about 40 mg of caffeine (the amount in about ½ cup of green tea2) yielded comparable or better results than the apple juice with 75 mg caffeine (the amount in about ½ cup of coffee). The apple juice with ~40 mg caffeine increased motivation, sustained attention and resulted in a faster reaction time compared to the other beverages and the placebo.

Should you guzzle the coffee for the caffeine, or “spiked” apple juice for the additional polyphenolic effects? More research is needed to say with certainty but this new evidence is quite exciting. Practitioners can add this “cognitive” piece of the caffeine puzzle to the extensive research on coffee and caffeinated beverages. Most importantly, and not covered in Dr. O’Connor’s talk, is the safety of caffeine. According to the Dietary Guidelines for Americans, up to 400 mg of caffeine can be incorporated into healthy eating patterns(3) This may be the sweet spot for those desiring the cognitive benefits of coffee while still balancing a healthy lifestyle. Dr. O’Connor made one point clear, that “caffeine effects how you feel as much as it affects how you perform”. Coffee drinkers, unite, and celebrate over your favorite (cold) brew.

 

  1. O’Connor P. Effects of Low Doses of Caffeine Added to Apple Juice and Cocoa on Mental Energy. Department of Foods and Nutrition Seminar. Athens, GA. August 31, 2016.
  2. Cabrera C, Reyes A, and Giménez R. Beneficial effects of green tea—a review. Journal of the American College of Nutrition. 2006;25:2:79-99.
  3. U.S. Department of Health and Human Services and U.S. Department of Agriculture. 2015 – 2020 Dietary Guidelines for Americans. 8th Edition. December 2015. Available at http://health.gov/dietaryguidelines/2015/guidelines/.