Eat Carbs in the Morning, Fat at Night?

MedicalResearch.com Interview with:
"Compare-the-Use-of-Carbohydrates-and-Lipids-in-Energy-Storage" by Zappys Technology Solutions is licensed under CC BY 2.0Kirsi-Marja Zitting, Ph.D.

Instructor in Medicine, Harvard Medical School
Division of Sleep and Circadian Disorders
Departments of Medicine and Neurology
Brigham and Women’s Hospital
Boston, MA 02115

MedicalResearch.com: What is the background for this study?

Response: This study is a follow-up study to our previous study where we found that chronic insufficient sleep together with chronic jet lag is associated with adverse changes in metabolism, including increase in blood sugar levels (Buxton et al. Science Translational Medicine, 2012). The present study focuses on the influence of the time of day on metabolism, which has not been investigated in humans independent of the effects of sleep, physical activity and diet.

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Can an Organic Diet Reduce Cancer Risk?

MedicalResearch.com Interview with:

"Sunday market in Paris: all organic food" by Richard Smith is licensed under CC BY 2.0Julia Baudry &
Emmanuelle Kesse-Guyot PhD
Centre de Recherche Epidémiologie et Statistique Sorbonne Paris Cité, Institut National de la Santé et de la Recherche Médicale (INSERM) U1153, Institut National de la Recherche

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Among the environmental risk factors for cancer, there are concerns about exposure to different classes of pesticides, notably through occupational exposure. Organic foods are less likely to contain pesticide residues than conventional foods, and studies have showed that an organic diet reduces exposure to certain pesticides (Baudry et al 2018, Oates et al 2014, Curl et al 2015). In the general population, the primary route of exposure is diet, especially intake of conventionally grown fruits and vegetables. However, few studies have examined the association of organic food consumption with cancer risk.

In a population of 68 946 French adults from the NutriNet-Santé study, we found a reduction of 25% of cancer risk among consumers with a high frequency of organic foods compared to consumers with a low frequency, after accounting for many factors (such as lifestyle, diet and sociodemographic factors). Specifically a 34% and 76% decrease in risk was observed for post-menopausal breast cancer and all lymphomas, respectively, among frequent organic food consumers compared to consumers with a low organic food consumption frequency.

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Study Finds No Need to Fear Carbohydrates

MedicalResearch.com Interview with:

Hana Kahleova, MD, PhD, MBA Director of Clinical Research Physicians Committee for Responsible Medicine Washington, DC 20016

Dr. Kahleova

Hana Kahleova, MD, PhD, MBA
Director of Clinical Research
Physicians Committee for Responsible Medicine
Washington, DC 20016 

MedicalResearch.com: What is the background for this study? What are the main findings? 

Response: The effects of carbohydrates on body weight and insulin sensitivity are controversial.

In this 16-week randomized clinical trial, we tested the role of carbohydrate quantity and quality, as part of a plant-based diet, on body weight, body composition, and insulin resistance. We have demonstrated that carbohydrates and dietary fiber play important roles in the regulation of body weight, body composition, and insulin resistance in overweight individuals.

Increased consumption of total carbohydrate was associated with a decrease in BMI and volume of visceral fat, even after adjustment for energy intake. Increased consumption of total and particularly insoluble fiber was associated with a decrease in BMI, fat mass, and volume of visceral fat.

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Two-Day Fast Per Week vs Daily Calorie Restriction in Diabetes

MedicalResearch.com Interview with:
“Diabetes Test” by Victor is licensed under CC BY 2.0Sharayah Carter
PhD candidate|BNutDiet|BMedPharmSc (Hons)|APD
School of Pharmacy and Medical Sciences
University of South Australia

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Intermittent energy restriction is a new popular diet method with promising effects on metabolic function but limited research exists on its effects on improving glycemic control in people with type 2 diabetes.

The findings of our research demonstrate that a diet with 2-days of severe energy restriction per week is comparable to a diet with daily moderate energy restriction for glycaemic control.  Continue reading

Does Your Morning Coffee Really Make You Eat Less?

MedicalResearch.com Interview with:
Coffee being poured Coffee pot pouring cup of coffee. copyright American Heart Association
Leah Panek-Shirley, PhD

Assistant Professor
Buffalo State College
Health, Nutrition, and Dietetics
Houston Texas

MedicalResearch.com: What is the background for this study? What are the main findings?


Response:
The findings of existing previous research evaluating the effects of caffeine on appetite and eating are equivocal.

This study evaluated the effects of no (0 mg/kg body weight, e.g. placebo), low (1 mg/kg body weight), and moderate (3 mg/kg body weight) doses of caffeine in juice on appetite and eating in the laboratory and under free-living conditions.

While this study identified a small decrease (about 70 calories) in caloric intake after consuming the low (1 mg/kg) dose of caffeine in the laboratory at breakfast, this difference did not persist throughout the entire day.  In addition, there were no differences in hunger, fullness, thirst, or desire to eat as a result of caffeine.

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So Far, Genes Don’t Explain How Many Calories We Consume

MedicalResearch.com Interview with:
“In-N-Out meal #1” by Chris Makarsky is licensed under CC BY 2.0Dr. Christina Holzapfel PhD
Junior Research Group Leader at
Institute for Nutritional Medicine
Technical University of Munich

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: A lot of articles about genetic factors and nutritional intake have been published in the last years. Findings are inconsistent and it is not clear, whether genetic variants, especially associated with body mass index, are associated with nutritional intake.

Therefore we performed a systematic literature search in order to get an overview about the association between single nucleotide polymorphisms and total energy, carbohydrate and fat intakes. We identified about specific search terms and their combinations more than 10,000 articles. Of these, 39 articles were identified for a relationship between genetic factors and total energy, carbohydrate, or fat consumption.

In all studies, we most frequently encountered the fat mass and obesity (FTO) associated gene as well as the melanocortin 4 receptor gene (MC4R). There are indications of a relationship between these two genes and total energy intake. However, the evaluation of the studies did not provide a uniform picture. There is only limited evidence for the relationship between the FTO gene and low energy intake as well as between the MC4R gene and increased energy intake.

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What is the Role of Diet in Psoriasis and Psoriatic Arthritis?

MedicalResearch.com Interview with:

Adam Ford, BS Research fellow with Dr. April Armstrong Keck School of Medicine University of Southern California

Adam Ford

Adam Ford, BS
Research fellow with Dr. April Armstrong
Keck School of Medicine
University of Southern California

MedicalResearch.com: What is the background for this study?

Response: Our psoriasis patients have long asked us about the role of diet on psoriasis. Previously, there was a lack of evidence synthesis on the relationship between psoriasis and diet. As such, providers were mostly unable to address their patients questions on the role of diet on psoriasis.

This pivotal effort from the National Psoriasis Foundation has been a few years in the making. We looked at the role of diet on psoriasis and psoriatic arthritis based on a careful synthesis of the scientific studies available to us currently.

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More Protein Associated With Moderate Increase in Heart Failure in Men (except for fish and eggs)

MedicalResearch.com Interview with:
“mmmm Meat” by Glen MacLarty is licensed under CC BY 2.0
Jyrki Virtanen, PhD
Adjunct professor of nutritional epidemiology
Heli Virtanen, MSc

University of Eastern Finland
Institute of Public Health and Clinical Nutrition
Kuopio, Finland 


MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Previous studies have found that animal sources of protein may have an adverse impact on the risk of cardiovascular diseases, like myocardial infarct, whereas plant sources of protein have had an opposite impact.

In this study we investigated that how protein intake from different dietary sources is associated with developing heart failure in men during the study’s follow-up. During the mean follow-up time of about 22 years, 334 men developed heart failure.

The main finding of the study was that higher protein intake was associated with a moderately higher risk of heart failure and the findings were similar with protein from most dietary sources, although the association was stronger with protein from animal sources. Only protein from fish and eggs were not associated with the risk in our study. Continue reading

Study Finds Plant-Based Diet Can Reduce Cardiovascular Death by 40%

MedicalResearch.com Interview with:
“Vegetarian Skewers” by Geoff Peters is licensed under CC BY 2.0Hana Kahleova, M.D., Ph.D.
Director of clinical research
Physicians Committee for Responsible Medicine
Washington, DC 20016 

MedicalResearch.com: What is the background for this study? What are the main findings? 

Response: In this study, my research team and I reviewed multiple clinical trials and observational studies to determine the links between diet and cardiovascular disease (CVD) risk. We found that a healthy diet can reduce the risk of heart attack by more than 80 percent—something no drug has ever accomplished.

We also found strong and consistent evidence that plant-based dietary patterns (with few or no animal products and rich in fruits, vegetables, grains, and legumes) can prevent and even reverse atherosclerosis and decrease other markers of CVD risk, including blood pressure, cholesterol, and weight. We found that a plant-based diet can reduce the risk of death from cardiovascular disease by about 40 percent overall.  Continue reading

Can a Dozen Eggs Per Week Be Safely Part of Overall Healthy Diet?

MedicalResearch.com Interview with:
“Eggs” by John Morgan is licensed under CC BY 2.0Nick Fuller PhD
Charles Perkins Centre Research Program Director
University of Sydney

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: There is a disparity in research findings between epidemiological studies and randomised controlled trials in those with type 2 diabetes mellitus. A lot of the research showing that a high egg consumption (6 or more eggs per week) is detrimental to a person’s health was conducted at a time when we were told to avoid eggs. People that were eating a high egg diet during that time were also likely to have other poor eating habits, such as one high in saturated fat and low in wholegrain carbohydrates. These studies did not control for such confounding factors.

As a result of this disparity in findings between epidemiological and controlled studies this has resulted in differing guidelines for recommended egg intake between countries.

To address a lack of randomised controlled trials in this field we conducted a large study over 12-months to assess the effect of a high egg consumption (12 eggs per week) on heart disease and diabetes risk factors in a group of people at high risk of cardiovascular heart disease – diagnosed with pre-diabetes or type 2 diabetes mellitus. 140 people were randomised to a high egg diet (12 eggs per week) or a low egg diet (less than 2 eggs per week) and advised on the principles of a healthy diet. For example, including plenty of wholegrain and low glycemic index carbohydrate sources and swapping sources of saturated fat (e.g. butter) for sources of poly and mono-unsaturated fat (e.g. avocado or olive oil). They followed their respective high or low egg diet for 12 months and over the time we measured a comprehensive list of risk factors for heart disease and type 2 diabetes.

Both the low and high egg groups had the same improvements in the health at the end of the 12 months and the high egg diet did not result in an increased risk of cardiovascular disease.

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Performance Drops Along With Weight on Ketogenic Diets

MedicalResearch.com Interview with:

Edward "Ted" Weiss, Ph.D. Associate Professor Department of Nutrition and Dietetics Saint Louis University Saint Louis MO 63104

Dr. Weiss

Edward “Ted” Weiss, Ph.D.
Professor
Department of Nutrition and Dietetics
Saint Louis University
Saint Louis MO 63104

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Ketogenic diets are popular. They are very low in carbohydrate, with moderate protein and large amounts of fat. They are popular for weight loss but definitive studies of this are lacking.

We tested the effects of a ketogenic diet on high-intensity exercise performance, such as sprinting. The result showed that the ketogenic diet was harmful to performance, reducing performance by 6 – 7% when compared to a high-carbohydrate diet.

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Middle Eastern Diet Linked To Improved Microbiome in Liver Patients

MedicalResearch.com Interview with:

“Turkish Food” by Garry Knight is licensed under CC BY 2.0Jasmohan S. Bajaj, M.D.
Associate Professor
Department of Internal Medicine
Division of Gastroenterology
Virginia Commonwealth University 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Altered gut microbiota composition can occur due to diseases and due to changes in the dietary practices. The interaction between these two and their linkage with clinical outcomes in liver diseases, such as cirrhosis is not clear from an international standpoint.

In this study we enrolled healthy subjects, and patients with cirrhosis who were either early or advanced in their process from USA and Turkey. We found that the Turkish subjects, who followed a Middle-eastern diet rich in vegetables and fermented milk products, had high microbial diversity, which was in turn associated with lower hospitalizations over 3 months. There was also an additional beneficial effect of coffee and tea intake. This protection persisted even when the clinical factors were accounted for. Continue reading

Small Intestinal Microbiome Adjusts To Dietary Fats and Sugar

MedicalResearch.com Interview with:

Eugene B. Chang, MD Martin Boyer Professor of Medicine Knapp Center for Biomedical Discovery University of Chicago Chicago, IL  60637

Dr. Chang

Eugene B. Chang, MD
Martin Boyer Professor of Medicine
Knapp Center for Biomedical Discovery
University of Chicago
Chicago, IL  60637 and

Kristina Martinez-Guryn, Ph.D., R.D. Assistant Professor  Biomedical Sciences Program Midwestern University Downers Grove, IL.

Dr. Martinez-Guryn

Kristina Martinez-Guryn, Ph.D., R.D.
Assistant Professor 
Biomedical Sciences Program
Midwestern University
Downers Grove IL

MedicalResearch.com: What is the background for this study? What are the main findings?

Dr. Martinez-Guryn: The original goal of this study was to understand why mice devoid of all microorganisms (germ free mice) are protected from diet-induced obesity. We demonstrate that these mice display severely impaired lipid absorption even when fed a high fat diet.

Dr. Chang: We found that many of the processes of dietary lipid digestion and absorption are dependent on and modulated by the gut microbiome which itself responds to dietary cues to adjust the small intestine’s ability and capacity to handle dietary lipids appropriately. This interplay is important for general health, but the findings are also relevant to conditions of overnutrition (obesity, metabolic syndrome) and undernutrition (starvation, environmental enteropathy).  In conditions of overnutrition, high fat, simple sugar, low fiber foods typical of western diets promote small intestinal microbes (which have been largely neglected by the scientific community) that promote fat digestion and absorption. This increases our capacity to assimilate dietary fats which can contribute to the overnutrition problem.  In conditions of undernutrition, these types of gut microbes are lost or minimally represented.  Thus, when nutritional repletion is started, the gut’s ability to upregulate its capacity for dietary lipid digestion and absorption is compromised.

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If You Lose Weight, Your Spouse Might Too

MedicalResearch.com Interview with:

Amy Gorin, Ph.D. Professor, Psychological Sciences Associate Director Institute for Collaboration on Health, Intervention, and Policy (InCHIP) University of Connecticut Storrs, CT   06269-1248

Dr. Gorin

Amy Gorin, Ph.D.
Professor, Psychological Sciences
Associate Director
Institute for Collaboration on Health, Intervention, and Policy (InCHIP)
University of Connecticut
Storrs, CT   06269-1248

MedicalResearch.com: What is the background for this study? What are the main findings?

Response:  This study examined whether behavioral weight management programs have a ripple effect on untreated spouses.  That is, if one member of a couple participates in a weight loss program, does the other untreated spouse benefit?  Given that many spouses are of a similar weight status, if one spouse is overweight, the other spouse tends to be overweight as well — understanding how weight management programs impact both spouses has important public health implications.

To examine this question, 130 spouses were randomly assigned to Weight Watchers or a self-guided control group. Spouses assigned to Weight Watchers group had only one member enrolled in a structured 6-month weight loss program (Weight Watchers) that provided in-person counseling and online tools to assist with weight loss.

In the self-guided group, one member of the couple received a four-page handout with information on healthy eating, exercise, and weight control strategies (e.g., choosing a low-fat, low-calorie diet, portion control). The results indicate that nearly one-third (32%) of untreated spouses in both groups lost ≥3% of their initial body weight (weight loss based on obesity management guidelines) at the 6-month mark, and weight losses did not differ between untreated spouses of Weight Watchers and self-guided participants.

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How Much DASH Diet is Required To Reduce Uric Acid?

MedicalResearch.com Interview with:
“Blood Pressure” by Bernard Goldbach is licensed under CC BY 2.0Stephen P. Juraschek, MD, PhD

Instructor of Medicine
Beth Israel Deaconess Medical Center/Harvard Medical School 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Recent evidence suggests that the DASH diet is associated with lower uric acid levels and lower risk of gout. Furthermore, a secondary analysis of the DASH trial showed that complete replacement of a typical American diet with the DASH diet lowered uric acid levels. However, it is unknown if partial replacement of a typical American diet with DASH foods might lower uric acid.

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Why Isn’t Your Diet Working? It’s In Your Genes

MedicalResearch.com Interview with:
“Scale model” by brett jordan is licensed under CC BY 2.0
William Barrington, PhD lead author on the study
Recently graduated PhD student from the Threadgill lab
David Threadgill, PhD
Texas A&M College of Medicine and
College of Veterinary Medicine & Biomedical Sciences, senior author

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Obesity and diet-induced diseases, such as cardiovascular disease, have reached epidemic proportions. The United States has offered universal dietary recommendations for decades, but they have been largely unsuccessful in reducing diet-induced diseases. These recommendations are largely built upon population-level data, which examines a large number of individuals and determines the average response to a dietary intervention. However, if there is large variation in responses within a population, then population-level data may be inadequate to improve health across genetically diverse individuals.

Our study used four genetically diverse types of mice to examine how one’s genetics interact with diet to influence obesity and risk factors for cardiometabolic disease. The study compared four popular human diets (American, Mediterranean, Japanese, and Maasai/ketogenic). While all mice suffered detrimental effects from the American diet, the severity of disease varied widely across the types of mice. In comparison, no single diet improved health across all strains, but there was one or more diets that improved health in each strain.

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Eating a Mostly Plant Based Diet Linked To Lower Risk of Heart Failure

MedicalResearch.com Interview with:
“Fresh Food” by Sonny Side Up! is licensed under CC BY 2.0

 

Dr. Kyla M Lara
Icahn School of Medicine at Mount Sinai

 

 

 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: This was the first study to evaluate whether dietary patterns of black and white adults living in the United States were associated with developing heart failure. We’re hearing a lot in the news about specific diets like low-fat, high protein, low carb, and other diets that decrease cardiovascular risk. We would love it, as physicians, if we could prescribe a specific diet to limit cardiovascular risk in our patients. I’m really excited about our study because instead of examining patterns of what we already know are healthy, we looked at foods people were regularly consuming in the United States and developed dietary patterns from this. This study is similar to other work we have done with stroke and heart attack.

We used data from the NIH funded REGARDS study, also known as the Reasons for Geographic and Racial Differences in Stroke. More than 30,000 white and African-American adults were recruited from 2003-2007. From this group, we studied over 18,000 adults who successfully completed a dietary assessment called the Food Frequency Questionnaire. This was a really great group to study because people who live in this particular geographic area of the Southeastern United States, also known as the stroke belt, suffer from a higher risk of death from stroke. It’s extremely important for us to better understand the major risk factors that contribute to this and also cardiovascular disease.

We used statistical techniques to derive 5 dietary patterns based on the types of foods participants tended to eat.
• Convenience – Mexican and Chinese food, mixed dishes (both meat and bean)
• Sweets – added fats, bread, chocolate, desserts, sweet breakfast foods
• Southern – added fats, fried food, organ and processed meat, fatty milk
• Alcohol/Salads – beer, wine, liquor, green leafy vegetables, salad dressings, nuts and seeds, coffee
• Plant Based- fruit, vegetables, fruit juice, cereal, fish, poultry

Each participant received a score for each pattern that reflected how closely their diet resembled that dietary pattern. This approach reflects the real world and how people eat.

Over the 3135 days (8.6 years) of median follow up, 594 participants were hospitalized for incident HF. Greatest adherence to the plant-based dietary pattern during the study period was associated with a 28% risk reduction of developing heart failure.
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DASH Diet and Sodium Reduction Can Have Big Impact in Improving Blood Pressure

MedicalResearch.com Interview with:

Stephen P. Juraschek, MD, PhD Instructor of Medicine Beth Israel Deaconess Medical Center/Harvard Medical School

Dr. Juraschek

Stephen P. Juraschek, MD, PhD
Instructor of Medicine
Beth Israel Deaconess Medical Center/Harvard Medical School 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: The DASH-Sodium trial demonstrated that both the DASH diet and sodium restriction, individually and combined, lowered blood pressure in adults with pre-hypertension or stage 1 hypertension. Whether these effects varied by level of blood pressure prior to starting these interventions was unknown. In a secondary analysis of the original DASH diet it had been observed that the effects from DASH were greater among adults with higher blood pressure (systolic greater than or equal to 140 mm Hg) at baseline with the appearance of even greater effects among people with baseline systolic blood pressures above 150 mm Hg. However, this has never been shown. Furthermore, it was unknown whether sodium reduction followed a similar linear trend of greater effects among adults with more severely uncontrolled systolic blood pressure.

In our study, we found that effects were indeed greater in adults with a baseline systolic blood pressure of 150 mm Hg or greater. Furthermore, the combined systolic blood pressure-lowering effect from both interventions was as high was 20 mm Hg. This is a magnitude comparable if not greater than medications for lowering blood pressure.

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Intermittent Dieting May Result In Greater Weight Loss

MedicalResearch.com Interview with:

Professor Nuala Byrne PhD Head of School | Health Sciences Faculty of Health University of Tasmania

Prof. Byrne

Professor Nuala Byrne PhD
Head of School | Health Sciences
Faculty of Health
University of Tasmania 

MedicalResearch.com: What is the background for this study?

Response: Calorie restriction (or cutting back on the energy we are eating) triggers powerful compensatory responses by our body’s metabolism – we might think of it as a “Famine Reaction”. Our body weight is regulated by a series of nervous system and hormone networks that act together to make sure we have enough energy to sustain life. When we eat more energy than our body needs to meet our daily metabolic requirements (positive energy balance), we are designed to store that excess energy; and we are very good at storing. We store this energy in the fat cells (adipocytes) as an emergency reserve for when we hit hard-times when food availability is scarce. The problem in today’s society is that most of us have a constant availability of energy-dense food; making it more common to be in energy excess.

When we have less calories being consumed than what we need to fuel all the body’s metabolic processes (negative energy balance), we convert the stored fat into usable energy, and consequently lose weight. While our body does sense the positive energy balance, it is designed to be more sensitive to gauging when we are in a negative energy balance. Our body senses the change in energy intake and the decreasing fat stores, and brings out the artillery to defend our energy stores – this is the Famine Reaction. Our body is constantly changing our physiology in response to challenges to the status quo; the body works constantly to keep the oxygen concentration in the blood at an optimal level, to keep a constant and optimal body temperature, and a constant and optimal amount of sugar in the blood. Our body’s regulatory systems also work hard to defend our energy stores if it senses we are continually in negative energy-balance (i.e., dieting). One major metabolic compensatory as part of the “Famine Reaction” is a decrease in the body’s resting metabolic rate (energy expended while at rest to maintain the basic functioning of our major organs). Given that resting metabolic rate is determined largely by body size and composition, it is expected to decrease with weight loss. However, during dieting, resting metabolic rate has been reported to decrease to a greater extent than that expected from changes in body composition, a phenomenon termed ‘adaptive thermogenesis’. This leads to markedly reduced efficiency of weight loss.

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Study Finds Diet Not Connected to GI Problems in Children With Autism

MedicalResearch.com Interview with:

Bradley James Ferguson, PhD University of Missouri School of Medicine

Dr. Ferguson

Bradley James Ferguson, PhD
University of Missouri School of Medicine 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Many individuals with autism spectrum disorder (ASD) have gastrointestinal problems, such as constipation, irritable bowel syndrome and abdominal pain, but the cause of these GI issues is not currently known. Previous research from our laboratory showed a significant positive relationship between cortisol levels and GI problems, especially for constipation. However, it is possible that other factors such as diet may affect GI functioning, especially since many children have altered diets. This study examined 32 different nutrients in the children’s diets, as assessed by a food frequency questionnaire that assessed the participant’s diet over the past month, and how each nutrient was related to upper and lower GI tract symptom scores over the past month created from the Questionnaire on Pediatric Gastrointestinal Symptoms – Rome III. The results showed no significant relationships between any of the nutrients and GI symptoms, suggesting that diet was not associated with GI symptoms in this sample.

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Which Diet Is Best For You? It Depends On Your Genes

MedicalResearch.com Interview with:

Kaixiong (Calvin) Ye, PhD Post-doctoral Associate Dept. of Biological Statistics & Computational Biology Cornell University thaca, NY

Dr. Kaixong Ye

Kaixiong (Calvin) Ye, PhD
Post-doctoral Associate
Dept. of Biological Statistics & Computational Biology
Cornell University
thaca, NY

MedicalResearch.com: What is the background for this study?

Response: Omega-6 and omega-3 fatty acids are critical for human brain development, cognitive function, immune response, and cardiovascular health. Physiologically active forms of omega-6 and omega-3 fatty acids, such as AA, EPA, and DHA, are readily available in meat and seafood, but are absent in most plant-based foods (e.g. fruits and vegetables). Instead, plant-based foods contain two precursor fatty acids, LA and ALA, which could be metabolized in our body and converted into physiologically active forms. Fatty acid desaturase (FADS) genes encode key enzymes for this biosynthesis.

We hypothesized that genetic variations in FADS genes that enhance the biosynthesis efficiency were adaptive to plant-based diets in traditional farming populations and thus became more frequent over time. Our study compiled a huge data set of genetic information (DNA) from both present-day and ancient individuals. For the first time, we examined the action of natural selection on humans for the past 30,000 years in Europe.

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Elegant Descriptions of Healthy Foods Encourages Consumption

MedicalResearch.com Interview with:

Bradley P. Turnwald

Bradley Turnwald

Bradley P. Turnwald MS
Stanford University, Department of Psychology
Stanford, California

MedicalResearch.com: What is the background for this study?

Response: This study tested an intervention to encourage people to consume healthier foods. Encouraging healthy eating is difficult because many people think that healthy foods do not taste good, and most people prioritize taste over health when choosing what to eat. In fact, lab studies suggest that people rate foods as less tasty, less enjoyable, and less filling when they are labeled as healthy compared to when the same foods are not labeled as healthy. A recent study from the Stanford Mind & Body Lab published last month in Health Psychology showed that healthy foods are even described with less tasty, exciting, and indulgent descriptions compared to standard items on the menus of top-selling chain restaurants in America. This led us to ask the question, what if healthy foods were described with the tasty and indulgent descriptions that are typically reserved for the more classic, unhealthy foods?

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Calorie Restriction Extends Life Through Protein Regulation

MedicalResearch.com Interview with:

John C. Price, Ph.D Asst. Professor Chemistry and Biochemistry Brigham Young University Provo, Utah

Dr. John Price

John C. Price, Ph.D
Asst. Professor Chemistry and Biochemistry
Brigham Young University
Provo, Utah

MedicalResearch.com: What is the background for this study?

Response: Since 1930 it has been known that the rate of biological aging could be modified by the diet.  In mice for example if you let them eat as much as they want they will live almost 3 years.  Providing essentially the same diet but controlling the number of total calories, there is an almost linear increase in lifespan as you restrict calories.  The studies in mice and rats have been repeated hundreds of times since that time.  There have been a lot of somewhat conflictive observations, like increased formation of new mitochondria, and increased autophagy which targets organelles for degradation, during stable reduced calorie intake. This expectation, that a restricted diet with fewer calories available to the animal could support increased protein synthesis and degradation and result in increased lifespan, is what got us interested in studying Calorie Restriction.  So we measured the relative synthesis rates for several hundred proteins in 18 month old calorie restricted mice which were experiencing the benefits of improved health and lifespan.  We found overwhelmingly that the calorie restricted mice had reduced synthesis rates down to as low as 25% of the age matched control group.  This observation has now been independently confirmed by multiple groups.

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Government Endorsed DASH Diet Voted Best Overall

MedicalResearch.com Interview with:

Janet M. de Jesus, M.S., R.D. Program Officer, Implementation Science Center for Translation Research and Implementation Science (CTRIS) National Heart, Lung, and Blood Institute

Janet de Jesus

Janet M. de Jesus, M.S., R.D.
Program Officer, Implementation Science
Center for Translation Research and Implementation Science (CTRIS)
National Heart, Lung, and Blood Institute

MedicalResearch.com: What is the background for the DASH diet? What are the main components?

Response: The DASH eating plan was created for a clinical trial funded by the National Heart, Lung, and Blood Institute (NHLBI). DASH stands for Dietary Approaches to Stop Hypertension. The goal of the original DASH trial was to test the eating plan compared to a typical American diet (at the time in the 1990s) on the effect of blood pressure.

The DASH eating plan is rich in fruits, vegetables, and whole grains. It includes low-fat dairy products, poultry, fish, legumes, vegetable oils, and nuts; and limits intake of sweets and sugar-sweetened beverages and high-fat meats. The eating plan is a good source of potassium, magnesium, and calcium. The DASH eating plan was shown to reduce blood pressure and improve lipid profiles.

A second DASH trial, “DASH-sodium,” showed that adding sodium reduction to the DASH eating plan reduced blood pressure even more.

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Low Carb Meals Reduce Insulin Resistance

MedicalResearch.com Interview with>
Katarina Borer, Ph.D. Professor
Po-Ju Lin,PhD
School of Kinesiology
The University of Michigan
Ann Arbor, MI

MedicalResearch.com: What is the background for this study?

Response: This study was part of the doctoral dissertation of Po-Ju Lin, who is now a post-doctoral fellow at the University of Rochester. With this study, we wanted to answer three questions:

(1) Is daily carbohydrate load responsible for evening glucose intolerance and post-meal insulin resistance. (Evening glucose intolerance represents well-documented higher glucose and insulin responses in the evening than in the morning when the same quantity of glucose is eaten or infused intravenously) To answer this question we offered two daily meals containing about 800 Kcal and either 30% or 60% of carbohydrates.

(2) Will exercise before the meals improve glucose tolerance (glucose clearance from the blood and insulin response) after eating? (Exercise is a well-known means of increasing glucose uptake by the muscle and of increasing muscle sensitivity to insulin action for a number of hours after exercise). To answer this question we had the subjects exercise for two hours walking on a treadmill at 45% of their maximal aerobic effort one hour before each meal.

(3) Is the upper-intestinal hormone GIP involved in any effects associated with variation in dietary carbohydrate? (GIP or glucose-dependent insulinotropic peptide, stimulates insulin secretion in advance of absorbed glucose).

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