MedicalResearch.com Interview with:
Man-tian Mi
Research Center for Nutrition and Food Safety,
Chongqing Key Laboratory of Nutrition and Food Safety,
Institute of Military Preventive Medicine,
Third Military Medical University
Chongqing China
MedicalResearch.com: What is the background for this study? What are the main findings?
Reply: Cardiovascular diseases remain the leading cause of death in industrialized societies including the United States, and the incidence is growing in developing countries (
1). In recent years, researchers have learned that the gut microbiome plays a role in the build up of plaque inside arteries, otherwise known as atherosclerosis (
2,
3). Resveratrol, a polyphenol found in red wine, is thought to have antioxidant properties that protect against conditions such as heart disease (
4). Just how resveratrol, a plant compound, does this, however, is unclear. Therefore, we sought to determine whether the anti-atherosclerosis effects of resveratrol were related to changes in the gut microbiota.
We found that resveratrol attenuated trimethylamine-N-oxide (TMAO)-induced atherosclerosis by decreasing TMAO levels and increasing hepatic bile acid (BA) neosynthesis
via gut microbiota remodeling, and the BA neosynthesis was partially mediated through the enterohepatic farnesoid X receptor-fibroblast growth factor 15 axis. These results offer new insights into the mechanisms responsible for resveratrol’s anti-atherosclerosis effects and indicate that gut microbiota may become an interesting target for pharmacological or dietary interventions to decrease the risk of developing cardiovascular diseases.
Lindsay Kohler[/caption]
Lindsay Kohler MPH
Mel and Enid Zuckerman College of Public Health
Tucson, Arizona
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Several studies have reported that following health promotion guidelines for diet, physical activity, and maintenance of a healthy body weight may reduce the risk of getting cancer or dying from cancer. We performed a systematic review to examine the associations between established cancer prevention guidelines for diet and physical activity and cancer outcomes. We found that adhering to cancer prevention guidelines set forth by the American Cancer Society or the World Cancer Research Fund/American Institute for Cancer Research consistently reduced the risk of overall cancer incidence and mortality (10-61%) in the studies included in this review. In addition, higher adherence to the guidelines consistently reduced the risk of breast, colorectal, and endometrial cancers. Adherence to a pattern of healthy behaviors may significantly reduce cancer incidence and mortality.
Dr. Ying Bao[/caption]
Dr. Ying Bao Sc.D., M.D
Assistant Professor of Medicine
Channing Division of Network Medicine
Department of Medicine
Brigham and Women's Hospital
Harvard Medical School,
Boston, MA
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Nuts are rich in bioactive macronutrients, micronutrients, tocopherols and phytochemicals. Current epidemiological evidence has consistently linked increased nut consumption to reduced risk of several chronic conditions including cardiovascular diseases, type 2 diabetes, and inflammation. In contrast, evidence on nut consumption and cancer risk has been insufficient and equivocal.
Prostate cancer is the leading cancer among U.S. men, with approximately 220,800 new cases diagnosed in 2015. However, very few studies have investigated the association between nut intake and prostate cancer. Thus, in the current study, we followed 47,299 US men from 1986-2012, and examined
(1) whether consuming more nuts prevents getting prostate cancer, and
(2) whether consuming more nuts reduces death rates among non-metastatic prostate cancer patients.
During 26 years of follow-up, 6,810 men were diagnosed with prostate cancer, and 4,346 of these patients were without metastasis at diagnosis. We found no association between nut intake and being diagnosed with prostate cancer. However, among non-metastatic prostate cancer patients, those who consumed nuts 5 or more times per week after diagnosis had a significant 34% lower rate of overall mortality than those who consumed nuts less than once per month.
Ambika Satija[/caption]
Ambika Satija
Departments of Nutrition & Epidemiology
Harvard T. H. Chan School of Public Health
Boston, MA
MedicalResearch.com: What is the background for this study?
Response: In this study, we followed more than 200,000 male and female health professionals across the U.S. for more than 20 years who had regularly filled out questionnaires on their diet, lifestyle, medical history, and new disease diagnoses as part of three large long-term studies.
Dr. Geng Zong[/caption]
Geng Zong, Ph.D.
Research fellow at Harvard T.H. Chan School of Public Health
Boston, Massachusetts.
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: The refining process of grains removes most of fiber, minerals, vitamins, polyphenols and alkyl resorcinols that mainly exist in the outer layer of a kernel, thus enriches grains with carbohydrate and energy. Whole grains, on the other hand, are cereal grains or processed cereal grains that contains bran and germ, in addition to the inner most endosperm, as their natural proportions in the kernel. Observational studies have repeatedly linked whole grain intake with major chronic diseases, including obesity, diabetes, cardiovascular diseases, and cancer, but findings regarding mortality are inconsistent and have not been quantitatively summarized. By meta-analyzing 14 existing or unpublished prospective cohort studies, our investigation found that whole grain intake is inversely associated with mortality risk from all-causes, CVD, and cancer. Among people with whole grain consumption, estimated all-cause mortality risk was 7% (for 10 grams/day), 16% (for 30 grams/day), 20% (for 50 grams/day), and 22% (for 70 grams/day) lower than people with no whole grain consumption. Similar dose-response relationship was observed for CVD and cancer mortality.
Dr. Ramon Estruch[/caption]
Dr Ramon Estruch, MD PhD
Senior Consultant in the Internal Medicine Department of the Hospital Clinic
Barcelona
MedicalResearch.com: What is the background for this study? What are the main findings?
Dr. Estruch: Although weight stability requires a balance between calories consumed and calories expended, it seems that calories from vegetable fats have different effects that calories from animals on adiposity. Thus, an increase of dietary fat intake (mainly extra virgin olive oil or nuts) achieved naturally in the setting of Mediterranean diet does not promote weight gain or increase in adiposity parameters such as waist circumference.
Dr. Jennifer Lemon[/caption]
Jennifer Lemon, PhD
Research Associate
Medical Radiation Sciences
McMaster University
MedicalResearch.com: What is the background for this study?
Dr. Lemon: Research with the supplement began in 2000, as part of my doctoral degree; we developed the supplement to try to offset the severe cognitive deterioration and accelerated aging in a mouse model we were working with in the lab. Based on aging research, five mechanisms appeared to be key contributors to the process of aging; those include oxidative stress, inflammation, mitochondrial deterioration, membrane dysfunction and impaired glucose metabolism. The criteria we used for including components in the supplement were as follows: each one of the 30 components had scientific evidence to show they acted on one or more of the above mechanisms were able to be taken orally, and were available to humans over-the-counter. Even then the hope was that if the formulation was successful, this would make it more available to the general public.
Dr. Meghan Azad[/caption]
Meghan Azad PhD
Assistant Professor, Department of Pediatrics & Child Health and Community Health Sciences
University of Manitoba
Associate Investigator, Canadian Healthy Infant Longitudinal Development (CHILD) Study
MedicalResearch.com: What is the background for this study?
Dr. Azad: It is well known that maternal nutrition plays a key role in “programming” fetal development and infant weight gain, but the impact of artificial sweetener consumption during this critical period has not been extensively studied. Some animal research suggests that consuming artificial sweeteners during pregnancy can predispose offspring to develop obesity, but this has never been studied in humans, until now.
Dr. Maryam Farvid[/caption]
MedicalResearch.com Interview with:
Maryam Farvid, Ph.D.
Visiting Scientist
Department of Global Health and Population
Harvard T.H. Chan School of Public Health
MedicalResearch: What is the background for this study? What are the main findings?
Dr. Farvid: Breast cancer is one of the most frequently diagnosed cancers and is the second leading cause of cancer deaths among women in the United States. While we know many breast cancer risk factors, few of them are easily modified. Further, evidence suggests that exposure to carcinogens and anti-carcinogens in early life may play an important role. According to this study, what women eat as teens or young adults could affect their breast cancer risk in the future. Teenage girls who eat a lot of fruits may have a lower risk of breast cancer later in life. The risk of breast cancer among women who reported the highest amount of 
Danielle Schoffman[/caption]
Danielle E. Schoffman
PhD Candidate
Department of Health Promotion, Education, and Behavior
Arnold School of Public Health
University of South Carolina
Columbia, SC 29208
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: In recent years, there has been large growth in the fast casual (e.g., Panera, Chipotle) restaurant sector, and there is a general perception among consumers that these restaurants are a healthier and fresher alternative to fast food. When we encourage participants in our research studies to reduce their fast food intake, they often ask if these fast casual restaurants also count. We were interested in looking at the calorie data for entrees at both restaurant types to see if they lined up with these assumptions.
We analyzed the calorie content of entrées at 34 fast food and 28 fast casual restaurants, and found that fast food entrées had an average of 760 calories per entrée compared to 561 for fast food entrées . Also, a greater proportion of fast casual restaurant entrées exceeded the median of 640 calories per entrée.
Dr. Jed Friedman[/caption]
Jacob (Jed) E. Friedman, Professor, Ph.D.
Department of Pediatrics, Biochemistry & Molecular Genetics
Director, NIH Center for Human Nutrition Research Metabolism Core Laboratory
University of Colorado Anschutz
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Scientists have long established that children who are breastfed are less likely to be obese as adults, though they have yet to identify precisely how breastfeeding protects children against obesity. One likely reason is that children who are breastfed have different bacteria in their intestines than those who are formula fed.
The study, published Monday in the American Journal of Clinical Nutrition examines the role of human milk hormones in the development of infants’ microbiome, a bacterial ecosystem in the digestive system that contributes to multiple facets of health.
“This is the first study of its kind to suggest that hormones in human milk may play an important role in shaping a healthy infant microbiome,” said Bridget Young, co-first author and assistant professor of pediatric nutrition at CU Anschutz. “We’ve known for a long time that breast milk contributes to infant intestinal maturation and healthy growth. This study suggests that hormones in milk may be partly responsible for this positive impact through interactions with the infant’s developing microbiome.”
Researchers found that levels of insulin and leptin in the breastmilk were positively associated with greater microbial diversity and families of bacteria in the infants’ stool. Insulin and leptin were associated with bacterial functions that help the intestine develop as a barrier against harmful toxins, which help prevent intestinal inflammation. By promoting a stronger intestinal barrier early in life, these hormones also may protect children from chronic low-grade inflammation, which can lead to a host of additional digestive problems and diseases.
In addition, researchers found significant differences in the intestinal microbiome of breastfed infants who are born to mothers with obesity compared to those born to mothers of normal weight. Infants born to mothers with obesity showed a significant reduction in gammaproteobacteria, a pioneer species that aids in normal intestinal development and microbiome maturation.
Gammaproteobacteria have been shown in mice and newborn infants to cause a healthy amount inflammation in their intestines, protecting them from inflammatory and autoimmune disorders later in life. The 2-week-old infants born to obese mothers in this study had a reduced number of gammaproteobacteria in the infant gut microbiome.
Evelyn Parr[/caption]
Evelyn Parr
Research Officer / PhD Candidate | Centre for Exercise and Nutrition
Mary MacKillop Institute for Health Research
Australian Catholic University
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Results from previous investigations suggest that compared to a healthy 'control' diet, increased consumption of dairy foods in an energy restricted diet lead to improved body composition (i.e., a loss of fat mass and the maintenance of lean mass).
We investigated the effects of manipulating the type of dairy foods (i.e., low- or high fat) within high protein, energy restricted diets on body composition and selected health parameters. Eighty-nine middle-aged (35-59 y), male and females who were overweight or obese completed a 16 week intervention comprising 3 d/wk supervised resistance training and 4 d/wk unsupervised aerobic -based exercise (i.e. walking). During this time they consumed a diet that was energy restricted by 250 kcal/d comprising either
1) high protein, moderate carbohydrate (4-5 normal fat dairy product servings),
2) high protein, high carbohydrate (4-5 low-fat, carbohydrate sweetened dairy product servings or
3) a control diet of moderate protein, high carbohydrate diet (1-2 dairy servings).
We found that in the face of energy restriction, when protein intakes were above the recommended daily intakes (>0.8 g/kg body mass) and regular exercise was completed, there was no difference in the loss of fat mass (~8 kg) when participants consumed 4-5 serves of dairy products in either low- or high-fat. Furthermore, participants maintained lean (muscle) mass throughout the energy restricted period.
