NewsMakers
Diets rich in polyunsaturated fats may alter appetite hormones
New published research shows millennials (ages 18-35) who regularly consume foods that contain polyunsaturated fats (PUFAs), such as walnuts, salmon and canola oil, may experience favorable changes in appetite hormones associated with hunger and satiety.
New published research shows millennials (ages 18-35) who regularly consume foods that contain polyunsaturated fats (PUFAs), such as walnuts, salmon and canola oil, may experience favorable changes in appetite hormones associated with hunger and satiety.1
Specific hormones in the body help control appetite. Some hormones are responsible for signaling the body to eat, whereas others tell the body it’s full, or satiated. Research is exploring how foods may reduce hunger or increase satiety by influencing these hormones. These types of hormonal changes could ultimately play a role in achieving optimal body weight.
In this study, researchers looked at physiological hunger and satiety responses by measuring hormone changes, as well as subjective ratings by asking participants to indicate on a scale how hungry or full they were and how much they thought they could eat. Study participants that consumed a diet high in PUFAs had a significant decrease in fasting ghrelin, a hormone that increases hunger, and a significant increase in peptide YY (PYY), a hormone that increases fullness or satiety. Participants saw increases in PYY while fasting and after consuming a meal. These types of hormone changes imply better appetite control. There were no changes in the subjective ratings in either the PUFA-rich diet or the control diet.
“Appetite hormones play an important role in regulating how much we eat,” said lead researcher, Jamie A. Cooper, PhD of the University of Georgia. “These findings tell us that eating foods rich in PUFAs, like those found in walnuts, may favorably change appetite hormones so that we can feel fuller for longer.”
Researchers enrolled 26 healthy men and women (ages 18-35) who visited the lab for measurements and to receive their meals throughout the study. At the beginning of the study, participants were measured and they consumed test meals high in saturated fat. Researchers then placed subjects on a seven-day diet high in PUFAs or a control diet consisting of a typical American eating pattern. The PUFA-rich diet included whole foods such as walnuts, Alaskasalmon, tuna, flaxseed oil, grapeseed oil, canola oil, and fish oil supplements. All meals were provided by the researchers. After the seven-day diet, participants consumed test meals high in saturated fat, again.
The two diets contained the same number of total calories and percent of calories from fat but differed in the types of fat included. The control diet was comprised of 7% polyunsaturated fat, 15% monounsaturated fat and 13% saturated fat, compared to the PUFA-rich diet which was 21% polyunsaturated fat, 9% monounsaturated fat, and 5% saturated fat.
Walnuts are unique among nuts because they are primarily comprised of PUFAs, with 13 out of 18 grams of total fat per one ounce serving. As a result, walnuts are the only nut to contain a significant amount of plant-based omega-3 alpha-linolenic acid (ALA) (2.5 grams per one ounce). Research on the health benefits of PUFAs continues to evolve and most recently the 2015-2020 Dietary Guidelines for Americans has recommended consuming this type of fat in place of saturated fat.
As with any research study, it is important to consider the limitations. Larger and longer-term studies, as well as studies in diverse populations, are needed to clarify population-wide effects. In the context of a whole food diet, such as the diet used in this study, it is difficult to discern whether changes seen with the PUFA-rich diet can be attributed to one specific type of PUFA, food source, or a combination of overall dietary factors. More clinical trials are needed to determine the optimal intake of dietary PUFAs to offer the greatest health benefit.
Funding for this research was provided by the California Walnut Commission (CWC). The CWC has supported health-related research on walnuts for more than 25 years. While the CWC does provide funds and/or walnuts for various projects, the actual studies are conducted independently by researchers who design the experiments, interpret the results and write the manuscripts.
|
Reference: |
|
1 Stevenson JL, Paton CM, Cooper JA. Hunger and satiety responses to high-fat meals after high polyunsaturated fat diet: a randomized trial. Nutrition. DOI:http://dx.doi.org/10.1016/j.nut.2017.03.008 |
NewsMakers
Common drug class may increase risk of heart disease
The risk of cardiovascular disease increased in line with how much anticholinergic medication the participants used each year. Those with the highest exposure had a 71 per cent higher risk of a cardiovascular event than people who did not use anticholinergic medication at all.
People who use drugs with anticholinergic effects, including certain antidepressants, drugs for urinary incontinence and common antihistamines, are at higher risk of developing cardiovascular disease.
This is shown in a study from Karolinska Institutet published in BMC Medicine.
Anticholinergic drugs reduce the effect of the neurotransmitter acetylcholine and are commonly prescribed to middle-aged and older people. This large group of drugs includes antihistamines used for allergic conditions, anxiety or insomnia, drugs for urinary incontinence, and certain antidepressants, where tricyclic antidepressants have a strong anticholinergic effect, whereas SSRIs have a weaker effect. A high cumulative use of these drugs, referred to as anticholinergic burden (see fact box), has previously been linked to impaired cognitive ability.
May affect heart regulation
The new study suggests that the drugs may also affect the parasympathetic nervous system and thereby the regulation of the cardiovascular system. The results show that it may be important to monitor the total drug burden in everyday clinical practice.
The study included more than 500,000 people in Stockholm, Sweden, who were 45 years of age or older and had no prior cardiovascular disease, except for hypertension, at the start of the study. The researchers followed the participants for up to 14 years and analysed how the use of anticholinergic drugs was associated with the development of cardiovascular disease.
“Many of these drugs are used by older people and by people with multiple medical conditions. We wanted to investigate whether the total exposure had any significance for the risk of developing cardiovascular disease over time,” says Nanbo Zhu, postdoctoral researcher at the Department of Neurobiology, Care Sciences and Society, Karolinska Institutet.
71 per cent higher cardiac risk
The study showed that the risk of cardiovascular disease increased in line with how much anticholinergic medication the participants used each year. Those with the highest exposure had a 71 per cent higher risk of a cardiovascular event than people who did not use anticholinergic medication at all. The association was seen for all types of cardiovascular disease but was particularly clear for heart failure and various forms of arrhythmia.
“Our results indicate that the cumulative drug burden can affect heart regulation, not only in the short term but also over the long term. This does not mean that the drugs should always be avoided, but that exposure should be monitored carefully,” says Hong Xu, assistant professor at the Department of Neurobiology, Care Sciences and Society.
The researchers point out that the study is observational, meaning it cannot establish a causal relationship. Other factors, such as underlying diseases, may also influence the associations.
The work was carried out within the Stockholm CREAtinine Measurements project in collaboration between several research groups at Karolinska Institutet and Region Stockholm. The study was funded by the Swedish Research Council, the Center for Innovative Medicine Foundation, and other foundations. Some researchers report assignments for the pharmaceutical industry, which are disclosed in the scientific publication.
NewsMakers
Mindfulness practices found to significantly reduce depression symptoms, especially for those with early-life adversity
Mindfulness interventions help by regulating our emotions better when different challenges come up. For someone who has experienced childhood neglect or abuse, mindfulness training can help us make sense of that and respond skillfully to this moment in time.
A new study reveals that mindfulness practices may significantly reduce depression symptoms, particularly in people who have experienced early-life adversity, such as childhood abuse and neglect.
Led by Eric Loucks, professor of medicine, epidemiology, and of behavioral and social sciences and director of the Mindfulness Center at Brown, the study enrolled 201 participants, 101 of whom were randomized into the Mindfulness-Based Blood Pressure Reduction Program, while 100 were randomized into an enhanced usual care control, which included home blood-pressure monitors, physician access and health-education materials. Researchers also had a measure of participants’ early-life adversity, particularly their exposure to abuse or neglect.
Loucks and his team followed participants for six months to assess changes in blood pressure, health behaviors and mental health, finding that those in the mindfulness program showed significant improvements in their depression symptoms. Additionally, participants who experienced childhood neglect showed greater improvements in depression symptoms than those who had not. A similar, though less pronounced, trend was observed among people with a history of childhood abuse.
“In this program, that was primarily designed to lower blood pressure while addressing whole-person health, we also saw that mental well-being, particularly around depression symptoms, improved in participants that went through the program,” Loucks said. “The findings suggest that cultivating mindful self-regulation skills–such such as self-awareness, attention control and emotion regulation–may help interrupt maladaptive patterns shaped by past experiences.”
Over the last 15 years, Loucks has been studying social determinants of health such as early-life adversity and its impacts on cardiovascular health, body mass index and blood pressure. “I came to a point where I wanted to not just document it, but do something about it, and I wondered if mindfulness training might help,” he said. “I’d gone through a lot of mindfulness training myself outside of work and started to get trained up in mindfulness programs that are specific to health contexts.”
Loucks began to study the Mindfulness-Based Stress Reduction program, running it through two clinical trials that were funded by the NIH and finding that it reduced blood pressure in both trials. He also wanted to look at the intervention from a whole-person perspective.
“If we look at everyday folks out in the world, those that had exposure to early life adversity, like abuse and neglect, tend to have worse mental health and also worse cardiovascular health,” Loucks said. “Mindfulness interventions help by regulating our emotions better when different challenges come up. For someone who has experienced childhood neglect or abuse, mindfulness training can help us make sense of that and respond skillfully to this moment in time.”
Loucks discussed this work during a keynote address at the U.S. DOHaD Society this year. “It felt like a coming-home moment to see that this intervention, originally developed to address psychosocial factors that influence health, had even stronger effects among people with early-life adversity, particularly on depression,” he said. “It’s been about a 15-year arc of research that culminated in these findings.”
NewsMakers
High-fiber diet linked to reduced risk of heart disease in night shift workers
A moderate intake of about 19 grams of fibre per day was linked to a lower risk for those who worked night shifts regularly. For those who worked night shifts sporadically, about 15 grams was enough. The current recommendation for adults is about 25 grams of dietary fibre per day.
People who work at night have a higher risk of coronary artery disease, a type of heart disease. A new study suggests that a higher fibre intake in the diet may help reduce this risk. The study included over 220,000 adults in the UK and is published in the European Journal of Epidemiology.
The human body is built to sleep at night. This means that working during the night goes against this natural pattern, and can place additional strain on the body, including the heart. Previous research has linked night work to an increased risk of coronary artery disease. Since night work is often unavoidable, the researchers wanted to investigate whether certain dietary habits might have a protective effect.
More fibre associated with lower risk
The researchers used data from 220,000 adults in the UK Biobank (2006–2010) and divided the participants into three groups:
- Day workers
- Shift workers who worked night shifts sporadically
- Regular night shift workers
The participants had completed a detailed questionnaire about their dietary habits. During a follow-up after about 12 years, it was found that night shift workers who consumed little fibre in their diet had a higher risk of coronary artery disease than those who consumed more fibre.
“A moderate intake of about 19 grams of fibre per day was linked to a lower risk for those who worked night shifts regularly. For those who worked night shifts sporadically, about 15 grams was enough. The current recommendation for adults is about 25 grams of dietary fibre per day,” says Diana Nôga, lead author and researcher at Uppsala University.
The researchers stress that the figures from the study are not official dietary recommendations. But they do show a pattern in this UK study: a higher dietary fibre intake was linked to a lower risk of heart disease among night shift workers.
“The link between fibre and a lower risk of heart disease is not just because those who eat more fibre generally have a healthier lifestyle. We know this because we adjusted for various lifestyle factors in the analysis. One possible explanation, supported by previous research, is that fibre in the diet can improve intestinal flora and also reduce lipids, which can be particularly good for the heart in people who work at night,” says Christian Benedict, senior author of the study and Professor of Pharmacology at Uppsala University.
Dietary fibre can support heart health
According to the researchers, an increased intake of fibre-rich foods such as whole grains, vegetables, fruit, legumes and lentils may be a simple way to improve heart health for night shift workers. However, this requires that you do not have any medical obstacles to doing this, such as chronic gastrointestinal diseases.
“Dietary changes should be seen as a complement to, not a substitute for, other heart health-promoting habits such as not smoking, remaining physically active, and getting enough sleep,” says Diana Nôga.
-
NewsMakers3 weeks agoCreativity feels great — until tomorrow
-
NewsMakers3 weeks agoHigh-fiber diet linked to reduced risk of heart disease in night shift workers
-
NewsMakers3 weeks agoSleeping in on weekends may help boost teens’ mental health
-
Wellness3 weeks agoExercise to treat depression yields similar results to therapy
-
Destinations3 weeks agoChecking the charm of Baguio City’s Café by the Ruins
-
NewsMakers3 weeks agoTwo types of underconfidence linked to anxiety and gender
-
Wellness3 weeks agoAerobic exercise may be most effective for relieving depression/anxiety symptoms
-
NewsMakers2 weeks agoMindfulness practices found to significantly reduce depression symptoms, especially for those with early-life adversity

