How high-intensity interval training can reshape metabolism

 Scientists have shed new light on the effects that high-intensity interval training (HIIT) has on human skeletal muscle, according to a study in men published today in eLife.

The findings suggest that HIIT boosts the amount of proteins in skeletal muscle that are essential for energy metabolism and muscle contraction, and chemically alters key metabolic proteins. These results may explain the beneficial effects of HIIT on metabolism and pave the way for additional studies exploring how exercise impacts these processes.

“Exercising has many beneficial effects that can help prevent and treat metabolic diseases, and this is likely the result of changes in energy use by skeletal muscles. We wanted to understand how exercise alters the muscles’ protein content and how it regulates the activity of these proteins through a chemical reaction called acetylation,” says first and co-corresponding author Morten Hostrup, Associate Professor at the Department of Nutrition, Exercise, and Sports at the University of Copenhagen, Denmark. Acetylation occurs when a member of the small molecule group, acetyl, combines with other molecules, and can affect the behaviour of proteins.

For their study, the team recruited eight healthy, untrained male volunteers to complete five weeks of high-intensity cycling training. The men worked out three times per week, finishing four minutes of cycling at a target rate of more than 90% of their maximum heart rate followed by a two-minute rest. They repeated this pattern four to five times per workout.

Using a technique called mass spectrometry, the team analysed changes to the composition of 3,168 proteins in tissue samples collected from the participants’ thighs before the study and after they completed the training. They also examined changes relating to 1,263 lysine acetyl-sites on 464 acetylated proteins.

Their analyses showed an increase in the production of proteins used to build mitochondria, which produce energy in cells, and in proteins related to muscle contractions. The team also identified increased acetylation of mitochondrial proteins and enzymes that are involved in the production of cellular energy. Additionally, they observed changes in the amount of proteins that reduce the skeletal muscle’s calcium sensitivity, which is essential for muscle contractions.

The results confirm some well-known changes to skeletal muscle proteins that occur after exercise, as well as identify new ones. For example, the reduced calcium sensitivity may explain why it can be harder for muscle contraction to occur after an athlete becomes fatigued. The work also suggests that exercise-induced changes in the regulation of proteins through acetylation may contribute to boosting metabolism.

“Using state-of-the-art proteomics technology, our study provides new information about how skeletal muscle adapts to exercise training, including the identification of novel exercise-regulated proteins and acetyl-sites,” concludes co-corresponding author Atul Deshmukh, Associate Professor at the Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen. “We hope our work will stimulate further research into how exercise helps improve metabolic health in humans.”

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Longer duration of exclusive breastfeeding has protective effect on childhood asthma

 

 Pregnant women and new mothers are often presented with information on the benefits of breastfeeding their infants. A new study in Annals of Allergy, Asthma and Immunology, the scientific journal of the American College of Allergy, Asthma and Immunology (ACAAI) shows that a longer period of exclusive breastfeeding was associated with decreased odds of current asthma.

“The results of the study indicated that the longer a mother exclusively breastfed, the lower the relative odds of her child having asthma, or asthma-related outcomes,” said Keadrea Wilson, MD, lead author of the study and Assistant Professor of Neonatology at the University of Tennessee Health Science Center. “There was a ‘dose-response’ effect depending on how long the mother breastfed: Babies that were breastfed for 2-4 months had only 64% likelihood of having as many asthma outcomes as those who were breastfed less than 2 months; those breastfed for 5-6 months had 61% likelihood, and those breastfed for more than 6 months had a 52% likelihood.”

The study combined three studies to get a large number of subjects – more than 2,000 mother-child pairs. In addition, by combining the studies, the authors achieved a demographic distribution. For example, 38% of the respondents were Black and 6% were Hispanic/Latina.

“A further finding of the study was that duration of breastfeeding mixed with formula/juices/other foods (so not exclusively breastfed) did not provide the same level of protection,” says allergist Angela Hogan, MD, vice chair of the ACAAI Asthma Committee. Dr. Hogan was not involved in the research. “Asthma runs in families, and according to the CDC, if a child has a parent with asthma, they are three to six times more likely to develop this condition than someone who does not have a parent with asthma. Anything a parent can do to lower the odds of their child getting asthma is worth considering.”

“Our study strengthens current breastfeeding recommendations which reflect recent analysis that show lower risk of asthma with more versus less breastfeeding,” said Dr. Wilson.

Allergists are specially trained to test for, diagnose and treat asthma. To find an allergist near you who can help create a personal plan to deal with your or your child’s asthma, and help them live their best life, use the ACAAI allergist locator.

 

 

Breastfeeding duration associated with cognition

 Breastfeeding duration is associated with improved cognitive scores at ages 5 through 14, even after controlling for socioeconomic position and maternal cognitive ability, according to a new study  https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0267326 published this week in the open-access journal PLOS ONE by Reneé Pereyra-Elías, Maria Quigley and Claire Carson of the University of Oxford, U.K.

Previous studies have found an association between breastfeeding and standardized intelligence test scores; however, a causal relationship is still debated. Improved cognitive outcomes could potentially be explained by other characteristics—such as socioeconomics and maternal intelligence—of the women who breastfeed their babies.

In the new study, the researchers analyzed data on 7,855 infants born in 2000-2002 and followed until age 14 as part of the UK Millennium Cohort Study. The cohort was not specifically designed to address the association between breastfeeding and cognition but included the collection of information on duration of any breastfeeding, duration of exclusive breastfeeding, verbal cognitive scores at ages 5, 7, 11, and 14, spatial cognitive scores at ages 5, 7 and 11, as well as potential confounders including socioeconomic characteristics and maternal cognition as based on a vocabulary test.

The unadjusted associations found that longer breastfeeding durations were associated with higher verbal and spatial cognitive scores at all ages up to ages 14 and 11, respectively. After taking the differences in socioeconomic position and maternal cognitive ability into account, children breastfed for longer scored higher in cognitive measures up to age 14, in comparison to children who were not breastfed. Longer breastfeeding durations were associated with mean cognitive scores 0.08 to 0.26 standard deviations higher than the mean cognitive score of those who never breastfed. This difference may seem small for an individual child but could be important at the population level.

The authors conclude that a modest association between breastfeeding duration and cognitive scores persists after adjusting for socioeconomics and maternal intelligence.

The authors add: “There is some debate about whether breastfeeding a baby for a longer period of time improves their cognitive development. In the U.K., women who have more educational qualifications and are more economically advantaged tend to breastfeed for longer. In addition, this group tends to score more highly on cognitive tests. These differences could explain why babies who breastfeed for longer do better in cognitive assessments. However, in our study, we found that even after taking these differences into account, children breastfed for longer scored higher in cognitive measures up to age 14, in comparison to children who were not breastfed. This difference may seem small for an individual child but could be important at the population level.”

 https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0267326

Seven healthy habits linked to lower risk of dementia

 Seven healthy habits and lifestyle factors may play a role in lowering the risk of dementia in people with the highest genetic risk, according to research published in the May 25, 2022, online issue of Neurology®, the medical journal of the American Academy of Neurology.

The seven cardiovascular and brain health factors, known as the American Heart Association’s Life’s Simple 7, are: being active, eating better, losing weight, not smoking, maintaining a healthy blood pressure, controlling cholesterol, and reducing blood sugar.

“These healthy habits in the Life’s Simple 7 have been linked to a lower risk of dementia overall, but it is uncertain whether the same applies to people with a high genetic risk,” said study author Adrienne Tin, PhD, of the University of Mississippi Medical Center in Jackson. “The good news is that even for people who are at the highest genetic risk, living by this same healthier lifestyle are likely to have a lower risk of dementia.”

The study looked at 8,823 people with European ancestry and 2,738 people with African ancestry who were followed for 30 years. People had an average age of 54 at the beginning of the study.

Study participants reported their levels in all seven health factors. Total scores ranged from 0 to 14, with 0 representing the most unhealthy score and 14 representing the most healthy score. The average score among those with European ancestry was 8.3 and the average score amongst those with African ancestry was 6.6.

Researchers calculated genetic risk scores at the start of the study using genome-wide statistics of Alzheimer’s disease, which have been used to study the genetic risk for dementia.

Participants with European ancestry were divided into five groups and those with African ancestry were divided into three groups based on genetic risk scores. The group with the highest genetic risk included people who had at least one copy of the APOE gene variant associated with Alzheimer’s disease, APOE e4. Of those with European ancestry, 27.9% had the APOE e4 variant, while of those who had African ancestry, 40.4% had the APOE e4 variant. The group with the lowest risk had the APOE e2 variant, which has been associated with a decreased risk of dementia.

By the end of the study, 1,603 people with European ancestry developed dementia and 631 people with African ancestry developed dementia.

For people with European ancestry, researchers found that people with the highest scores in the lifestyle factors had a lower risk of dementia across all five genetic risk groups, including the group with the highest genetic risk of dementia. For each one-point increase in the lifestyle factor score, there was a 9% lower risk of developing dementia. Among those with European ancestry, compared with the low category of the lifestyle factor score, the intermediate and high categories were associated with 30% and 43% lower risk for dementia, respectively. Among those with African ancestry, the intermediate and high categories were associated with 6% and 17% lower risk for dementia, respectively.

Among people with African ancestry, researchers found a similar pattern of declining dementia risk across all three groups among those with higher scores on the lifestyle factors. But researchers said the smaller number of participants in this group limited the findings, so more research is needed.

“Larger sample sizes from diverse populations are needed to get more reliable estimates of the effects of these modifiable health factors on dementia risk within different genetic risk groups and ancestral backgrounds,” Tin said.

A limitation of the study was the smaller sample size among people with African ancestry and that many African American participants were recruited from one location.

The study was supported by the National Heart, Lung, and Blood Institute, the National Institutes of Health, the Department of Health and Human Services, and the National Human Genome Research Institute.

Learn more about dementia at BrainandLife.org, home of the American Academy of Neurology’s free patient and caregiver magazine focused on the intersection of neurologic disease and brain health. Follow Brain & Life® on Facebook, Twitter and Instagram.

When posting to social media channels about this research, we encourage you to use the hashtags #Neurology and #AANscience.

The American Academy of Neurology is the world’s largest association of neurologists and neuroscience professionals, with over 38,000 members. The AAN is dedicated to promoting the highest quality patient-centered neurologic care. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as Alzheimer’s disease, stroke, migraine, multiple sclerosis, concussion, Parkinson’s disease and epilepsy.

For more information about the American Academy of Neurology, visit AAN.com or find us on Facebook, Twitter, Instagram, LinkedIn and YouTube.

Eating eggs can boost heart health

 

Researchers have shown how moderate egg consumption can increase the amount of heart-healthy metabolites in the blood, publishing their results today in eLife.

The findings suggest that eating up to one egg per day may help lower the risk of developing cardiovascular disease.

Eggs are a rich source of dietary cholesterol, but they also contain a variety of essential nutrients. There is conflicting evidence as to whether egg consumption is beneficial or harmful to heart health. A 2018 study published in the journal Heart, which included approximately half a million adults in China, found that those who ate eggs daily (about one egg per day) had a substantially lower risk of heart disease and stroke than those who ate eggs less frequently*. Now, to better understand this relationship, the authors of this work have carried out a population-based study exploring how egg consumption affects markers of cardiovascular health in the blood.

“Few studies have looked at the role that plasma cholesterol metabolism plays in the association between egg consumption and the risk of cardiovascular diseases, so we wanted to help address this gap,” explains first author Lang Pan, MSc at the Department of Epidemiology and Biostatistics, Peking University, Beijing, China.

Pan and the team selected 4,778 participants from the China Kadoorie Biobank, of whom 3,401 had a cardiovascular disease and 1,377 did not. They used a technique called targeted nuclear magnetic resonance to measure 225 metabolites in plasma samples taken from the participants’ blood. Of these metabolites, they identified 24 that were associated with self-reported levels of egg consumption.

Their analyses showed that individuals who ate a moderate amount of eggs had higher levels of a protein in their blood called apolipoprotein A1– a building-block of high-density lipoprotein (HDL), also known as ‘good lipoprotein’. These individuals especially had more large HDL molecules in their blood, which help clear cholesterol from the blood vessels and thereby protect against blockages that can lead to heart attacks and stroke.

The researchers further identified 14 metabolites that are linked to heart disease. They found that participants who ate fewer eggs had lower levels of beneficial metabolites and higher levels of harmful ones in their blood, compared to those who ate eggs more regularly.

Low glycemic index diet helps heart patients lose weight

  Eating low glycaemic index foods promotes a healthier body shape in patients with coronary artery disease, according to a study presented at ACNAP-EuroHeartCare Congress 2022, a scientific congress of the European Society of Cardiology (ESC).1

The glycaemic index (GI) ranks carbohydrate-containing foods according to how quickly they affect blood sugar levels. High GI foods cause a rapid increase in blood sugar and include white bread, white rice, potatoes and sweets. Low GI foods are digested more slowly and gradually raise blood sugar; they include some fruits and vegetables such as apples, oranges, broccoli and leafy greens, pulses such as chickpeas, lentils, and kidney beans, and wholegrains such as brown rice and oats. Meat, poultry and fish do not have a GI rating because they do not contain carbohydrates.

Observational studies have previously indicated that high GI diets are associated with increased risks of cardiovascular disease2 and type 2 diabetes.3 This randomised controlled study assessed the potential benefit of a low GI diet on body mass index (BMI), waist circumference, hip circumference and waist-to-hip ratio in patients with coronary artery disease.

Between 2016 and 2019, the study randomly allocated 160 patients aged 38 to 76 years old to three months of either a low GI diet or routine diet. Both groups continued to receive standard therapies for coronary artery disease. Patients in the low GI group were advised to consume low GI foods and exclude high GI foods while continuing  their usual consumption of protein and fat. The routine diet group was advised to consume the recommended diet for coronary artery disease which limits fat and some proteins such as whole milk, cheese, meat, egg yolks and fried foods. Dietary adherence was assessed with a food frequency questionnaire. Anthropometric indices were measured at baseline and three months.

The average age of participants was 58 years and 52% were women. Anthropometric indices were similar between groups at baseline. At three months, all body measurements had decreased within both groups compared to baseline but the changes were only significant in the low GI group.

When the researchers compared changes from baseline to study completion between groups, the low GI diet led to significant reductions in BMI and waist circumference. BMI declined by 4.2 kg/m2 in the low GI group compared to 1.4 kg/m2 in the routine diet group. Waist circumference decreased by 9 cm in the low GI group compared with 3.3 cm in the routine diet group. There was no significant difference between groups for hip circumference and waist-to-hip ratio.

The researchers also investigated whether the intervention affected women and men differently. They found that a low GI diet was more likely to influence waist circumference, hip circumference and waist-to-hip ratio in men compared with women. The beneficial effect of a low GI diet on BMI was the same for men and women.

Lifestyle changes, metformin effective to prevent or delay Type 2 diabetes

 A lifestyle intervention program of increased physical activity, healthy eating and aiming for weight loss of 7% or more, or taking the medication metformin were effective long-term to delay or prevent Type 2 diabetes in adults with prediabetes. Neither approach, however, reduced the risk of cardiovascular disease for study participants over 21 years of the study, according to the findings of the  multicenter Diabetes Prevention Program Outcomes Study (DPPOS), published today in the American Heart Association’s flagship, peer-reviewed journal Circulation.

Type 2 diabetes (T2D) is the most common form of diabetes, affecting more than 34 million people in the U.S., representing nearly 11% of the U.S. population, according to the U.S. Centers for Disease Control and Prevention’s 2020 National Diabetes Statistics Report, and cardiovascular disease (CVD) is the leading cause of death and disability among people with T2D. Type 2 diabetes occurs when the body is unable to efficiently use the insulin it makes and the pancreas is unable to produce sufficient amounts of insulin. Adults with T2D are twice as likely to die from CVD — including heart attack, stroke or heart failure — compared to adults who do not have T2D. People with T2D often have other cardiovascular disease risk factors, including being overweight or having obesity, high blood pressure or high cholesterol.

The DPPOS evaluated 21-years of follow-up (through 2019) for the 3,234 adults who participated in the original, 3-year Diabetes Prevention Program (DPP) trial. This analysis of the DPPOS was focused on determining whether the medication metformin or lifestyle intervention might reduce the risk of cardiovascular disease or the rate of major cardiac events such as heart attack, stroke or death due to cardiovascular disease.

“The risk of cardiovascular disease in people with prediabetes is increased, and CVD risk further increases over time after Type 2 diabetes develops and progresses,” said Ronald B. Goldberg, M.D., chair of the writing group for the DPPOS and a professor of medicine, biochemistry and molecular biology in the division of diabetes, endocrinology and metabolism, and senior faculty member and co-director of the Diabetes Research Institute Clinical Laboratory at the University of Miami’s Miller School of Medicine in Miami, Florida. “We were focused on assessing the impact of lifestyle or metformin interventions for prevention of Type 2 diabetes in people with prediabetes to reduce cardiovascular disease.”

The DPP was a landmark, 27-center randomized trial across the U.S. from 1996-2001 to assess how to prevent or delay the onset of T2D in people with prediabetes. Study participants were screened and accepted in the DPP based upon these criteria: initially, a 2-hour glucose reading of 140-199 mg/dL on an oral glucose tolerance test; fasting glucose levels of 95-125 mg/dL; and body mass index of 24 kg/m2 or higher.

A racially diverse group of 3,234 adults were studied in the original DPP for almost three years. The participants were an average age of 51 years, and nearly 70% of the participants were women. People in the intensive lifestyle intervention group (nutritional improvement and physical activity aimed at achieving a weight loss of 7%) reduced the incidence of developing T2D by 58%, and participants who took twice daily doses of metformin had a reduced incidence of 31% for T2D, when compared to people in the placebo group who received standard care, which included information about effective treatment and management of T2D at the time of diagnosis.

The DPPOS began in 2002 and was open to all participants in the original DPP trial. The DPPOS enrolled almost 90% of the original study participants for up to 25 years of follow-up to assess the long-term impact of the interventions on the development of T2D and its complications. Due to the success of the lifestyle intervention, everyone in the study was offered enrollment in the lifestyle intervention through a group format during a one-year bridge period. The group who took metformin in the original DPP trial were able to continue take the medication during the DPPOS, and  they were aware that they were taking metformin not the placebo. (The metformin and placebo groups were blinded in the original DPP, so participants did not know whether they were taking metformin or placebo during that time period.)

“From the beginning of the Diabetes Prevention Program, we were primarily interested in whether prevention of diabetes would lead to a reduction in the development of the complications that are caused by Type 2 diabetes — cardiovascular disease, kidney disease, retinopathy and neuropathy,” said Goldberg. “Managing blood glucose levels is important, and we encourage interventions to prevent the long-term complications of Type 2 diabetes.”

The DPPOS assessed cardiovascular disease outcomes in order to determine the effects of lifestyle and metformin interventions on participants’ risk of having a non-fatal heart attack, stroke or death due to a cardiovascular occurrence, by comparing outcomes of each intervention group to the placebo group. Researchers reported results based on a median follow-up of 21 years, which included the average three-year follow-up period of the original DPP trial. The authors conducted a futility analysis of the cardiovascular outcomes, which resulted in ending the study prior to completing the planned 25-year follow-up.

Throughout the entire study, participants were screened annually with electrocardiogram testing; measures of their cardiovascular disease risk factors, including smoking, cholesterol levels and blood pressure levels; and body mass index measurements. The percentage of all participants taking blood pressure and cholesterol lowering medications increased over the duration of the study and was slightly lower among the participants in the lifestyle group versus the other two groups.

After an average 21 years of follow-up, researchers found no significant differences in the incidence of heart attacks, stroke or cardiovascular death among the three intervention groups. Specifically, the analysis found:

• There was a continued reduction or delay in the development of T2D for up to 15 years.
• The number of non-fatal heart attacks across each group was similar: 35 heart attacks occurred in the lifestyle intervention group; 46 in the metformin group; and 43 in the placebo group.  
• Similarities were also found in the number of non-fatal strokes: 39 incidences of stroke in the lifestyle intervention group; 16 in the metformin-only group; and 28 in the placebo group.
• The number of deaths due to cardiovascular occurrences were low: 37 deaths among the lifestyle intervention participants; 39 in the metformin group; and 27 in the participants who took the placebo during the original DPP trial.

“The fact that neither a lifestyle intervention program nor metformin led to a decrease in cardiovascular disease among people with prediabetes may mean that these interventions have limited or no effectiveness in preventing cardiovascular disease, even though they are highly effective in preventing or delaying the development of Type 2 diabetes,” said Goldberg. “It’s important to note that most study participants also received treatment with cholesterol and blood pressure medications, which are known to reduce CVD risk. Therefore, the low rate of development of cardiovascular disease found overall may have been due to these medications, which would make it difficult to identify a beneficial effect of lifestyle or metformin intervention. Future research to identify higher risk subgroups is needed to develop a more targeted approach to cardiovascular disease prevention in people with prediabetes and Type 2 diabetes.”

There were several limitations to the study. The researchers selected a subgroup of people who met the criteria for prediabetes, however, these results are not generalizable to everyone with prediabetes. Additionally, the intensity of the lifestyle intervention was reduced after the initial DPP phase, and, over the 21-year study period, there was a gradual reduction in medication adherence by participants in the metformin group. There was also out-of-study metformin use in patients who were diagnosed with Type 2 diabetes, which may have diluted differences among the study groups. The high level of blood pressure and cholesterol medications prescribed by the participants’ primary care team, as well as lower use of blood pressure medications in the lifestyle group, may have influenced results. There may have also been some under-estimation of cardiovascular events since some participants did not complete 21 years of follow-up.

”These long-term findings confirm the link between Type 2 diabetes and cardiovascular disease is complex and requires more research to understand it better,” said the American Heart Association’s Chief Medical Officer for Prevention Eduardo Sanchez, M.D., M.P.H., FAHA, FAAFP, and clinical lead for Know Diabetes by Heart, a collaborative initiative between the American Heart Association and the American Diabetes Association addressing the link between diabetes and cardiovascular disease. “However, these important results also tell us that lifestyle intervention is incredibly effective to delay or prevent Type 2 diabetes, which, itself, reduces the risk for cardiovascular disease. The CDC estimates nearly 1 of every 3 adults in the U.S. has prediabetes, therefore, preventing or delaying Type 2 diabetes is a public health imperative to help extend and improve the lives of millions of people.” 

Additional Resources:

• Multimedia is available on right column of release link: https://newsroom.heart.org/news/lifestyle-changes-meds-effective-to-prevent-or-delay-type-2-diabetes-no-change-in-cvd?preview=d692bdc545131050271fdabd7e4d21f0
• After May 23, view the manuscript online.
• AHA Scientific Statement: Less than 1 in 5 adults with Type 2 diabetes in the U.S. are meeting optimal heart health targets (January 2022)
• AHA health information: Cardiovascular Disease and Diabetes
• Know Diabetes by Heart
• Follow AHA/ASA news on Twitter @HeartNews
• Follow news from the AHA’s flagship journal Circulation @CircAHA

Cranberries could improve memory and ward off dementia

 

Adding cranberries to your diet could help improve memory and brain function, and lower ‘bad’ cholesterol – according to new research from the University of East Anglia (UK).

A new study published today highlights the neuroprotective potential of cranberries.

The research team studied the benefits of consuming the equivalent of a cup of cranberries a day among 50 to 80-year-olds.

They hope that their findings could have implications for the prevention of neurodegenerative diseases such as dementia.

Lead researcher Dr David Vauzour, from UEA’s Norwich Medical School, said: “Dementia is expected to affect around 152 million people by 2050. There is no known cure, so it is crucial that we seek modifiable lifestyle interventions, such as diet, that could help lessen disease risk and burden.

“Past studies have shown that higher dietary flavonoid intake is associated with slower rates of cognitive decline and dementia. And foods rich in anthocyanins and proanthocyanidins, which give berries their red, blue, or purple colour, have been found to improve cognition.

“Cranberries are rich in these micronutrients and have been recognized for their antioxidant and anti-inflammatory properties.

“We wanted to find out more about how cranberries could help reduce age-related neurodegeneration.”

The research team investigated the impact of eating cranberries for 12 weeks on brain function and cholesterol among 60 cognitively healthy participants.

Half of the participants consumed freeze-dried cranberry powder, equivalent to a cup or 100g of fresh cranberries, daily. The other half consumed a placebo.

The study is one of the first to examine cranberries and their long-term impact on cognition and brain health in humans.

The results showed that consuming cranberries significantly improved the participants’ memory of everyday events (visual episodic memory), neural functioning and delivery of blood to the brain (brain perfusion).

Dr Vauzour said: “We found that the participants who consumed the cranberry powder showed significantly improved episodic memory performance in combination with improved circulation of essential nutrients such as oxygen and glucose to important parts of the brain that support cognition – specifically memory consolidation and retrieval.

“The cranberry group also exhibited a significant decrease in LDL or ‘bad’ cholesterol levels, known to contribute to atherosclerosis – the thickening or hardening of the arteries caused by a build-up of plaque in the inner lining of an artery. This supports the idea that cranberries can improve vascular health and may in part contribute to the improvement in brain perfusion and cognition.

“Demonstrating in humans that cranberry supplementation can improve cognitive performance and identifying some of the mechanisms responsible is an important step for this research field.

“The findings of this study are very encouraging, especially considering that a relatively short 12-week cranberry intervention was able to produce significant improvements in memory and neural function,” he added.

“This establishes an important foundation for future research in the area of cranberries and neurological health.”

Wearing a compression garment during or after training does not facilitate muscle recovery

 Compression garments are an elastic cloth fitting that people wear on their arms, legs, or hips during or after physical exercise. Their use has gained popularity over the last few decades because they are thought to enhance muscle recovery following exercise.

An international research team, led by assistant professor János Négyesi from Tohoku University's Graduate School of Biomedical Engineering, performed a systematic review with meta-analysis to assess whether compression garments assist with muscle recovery.

Systematic reviews identify and synthesize data from all relevant studies, and sit at the highest level on the evidence-based medicine pyramid. The researcher's review used a generic inverse variance model, which adjusts the weight of individual studies according to sample size, to more accurately assess the effects of compression garments than previous meta-analyses.

Contrary to results found in individual research, the meta-analytical evidence suggests that wearing a compression garment during or after training does not facilitate muscle recovery.

"Even data from our previous study supported the idea that such garments have the potential to reduce strength loss after a strenuous workout," said Dr. Négyesi. "However, when we synthesized the data of all relevant studies, we found no effect of compression garments on strength recovery - even when factoring in exercise type and when and where the compression garment is applied."

The authors think this is a perfect example of contradictory outcomes from individual studies and meta-analytical evidence. Therefore, scientists should be careful when drawing direct conclusions from the results of their studies. Rather, meta-analyses using the most appropriate models can provide more precise and reliable results.

Overall, practitioners, athletes, coaches, and therapists should reconsider compression garments as a means of reducing the harmful effects of physical exercise on muscle strength and seek alternative methods.

The review paper was published in Sports Medicine on April 27, 2022.

Physical activity and healthy diet during menopause help to protect from the health risks associated with increased adiposity

A study conducted in the Faculty of Sport and Health Sciences at the University of Jyväskylä, Finland, revealed that menopausal transition increases women’s body fat especially in the waist area. Therefore, to alleviate the health risks related to fat accumulation, women are recommended in mid-life to pay special attention to good lifestyle habits—physical activity and healthy diet—to help alleviate the health risks related to fat accumulation.

In the period of life prior to and after menopause, women tend to accumulate more fat in their bodies; the distribution of fat in the different regions of the body changes as well. Before menopause, women typically have more fat in their thigh and gluteal areas compared to men, but in midlife many women notice the increase of fat especially in their waist area. In addition to the total amount, the location of this adipose tissue also is meaningful to one’s overall health, especially because mid-region fat has been shown to increase the risk for cardiovascular disease and type 2 diabetes.

“Aging increases total body adipose tissue accumulation in both men and women, but it seems that menopause may accelerate these changes in women,” says doctoral researcher Hanna-Kaarina Juppi. “Although several studies have been conducted on this issue, the role of menopause specifically in the changing fat distribution is still under debate. Since women typically live in the postmenopausal state for several decades, it is crucial to study these changes and understand their meaning to health.”

In the current study, middle-aged women approaching menopause were followed for a maximum of 4 years over the menopausal transition. At the beginning and end of the study, women’s body composition, mid-thigh adipose tissue area, and adipose-tissue-derived hormones from their blood were measured. Information was collected also regarding the level of physical activity, diet, and the use of hormone therapy. Fat accumulation was investigated also at the muscle fibre level. During the follow-ups, researchers found an increase in the fat mass over the entire body, with a notable increase in the waist area. Women who were more physically active and partook in a healthier diet during the study had lower fat mass. The use of hormone preparations was not associated with body fatness.

“The results indicate that menopause affects body fat accumulation in women. Contrary to expectations, the increase in the amount of adipose tissue of our participants had only moderately negative effects on the hormones derived from the adipose tissue that reflect metabolic health,” Juppi continues. “We suspect that the relatively healthy lifestyle habits of our participants helped them sustain metabolic health despite an increase in fat mass and menopause.”

Conducted at the Gerontology Research Center in the Faculty of Sport and Health Sciences at the University of Jyväskylä, this research is part of the Estrogenic Regulation of Muscle Apoptosis (ERMA) and Estrogen, MicroRNAs and the Risk of Metabolic Dysfunction (EsmiRs) studies led by Associate Professor Eija Laakkonen. Nearly 1,400 Finnish women aged 47 to 55 years old participated in the original ERMA baseline. Of them, 230 women participated in the ERMA and 148 to the EsmirS follow-up studies. The research has been funded by Academy of Finland.

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JOURNAL

Aging Cell

DOI

10.1111/acel.13621 

New weight-loss intervention targets instinctive desire to eat

 People who are highly responsive to food lost more weight and, importantly, were more successful at keeping the pounds off using a new alternative weight-loss intervention that targets improving a person’s response to internal hunger cues and their ability to resist food, reported a team led by University of California San Diego experts in the May 18, 2022 online issue of JAMA Network Open.

“There are individuals who are very food cue responsive. That is, they cannot resist food and/or cannot stop thinking about food. Behavioral weight loss skills are not sufficient for these individuals, so we designed an alternative approach to address this clinical need,” said first author Kerri N. Boutelle, PhD, UC San Diego professor in the Herbert Wertheim School of Public Health and Human Longevity Science and in the School of Medicine Department of Pediatrics.

Approximately 74% of adults in the United States are living with overweight or obesity. Behavioral weight loss programs, that include calorie counting, have been the go-to treatment. However not everyone responds, and most people regain the lost weight.

For those who find it difficult to resist food, weight loss can be particularly challenging. This food responsiveness is both hereditary and shaped by the environment and individual factors.

In the Providing Adult Collaborative Interventions for Ideal Changes (PACIFIC) randomized clinical trial, the researchers compared their intervention, called Regulation of Cues, against a behavioral weight loss program, a control group, and a cohort that combined Regulation of Cues with the behavioral program.

Weight loss was comparable after 24 months among individuals in both the Regulation of Cues and the behavioral weight loss program.

However, participants in the Regulation of Cues arm stabilized their weight and kept it off while participants in the other groups regained weight at mid-treatment when clinic visits were reduced to monthly.

“Our findings suggest that the appetitive mechanisms targeted by Regulation of Cues may be especially critical for weight loss among individuals who have trouble resisting food and could be used in a personalized medicine approach,” said Boutelle.

According to the Centers of Disease Control and Prevention, overweight and obesity are risk factors for heart disease, stroke, Type 2 diabetes, and some cancers, all of which are among the leading causes of preventable death.

Over a 12-month period, 271 adults aged 18 to 65 attended 26 group treatments. They were all asked to engage in at least 150 minutes of moderate or vigorous intensity physical activity per week.

The Regulation of Cues intervention did not prescribe participants with a diet. Instead, it trained the use of natural cues of when to eat rather than focusing on calories, it reinforced tolerance of cravings, and focused on inhibiting urges to eat palatable foods when not physically hungry.

Palatable foods — usually food that contain high amounts of sugar or fat with the additional of salt and flavorings — stimulate the reward system in the brain and can be particularly challenging to resist.

The control arm provided nutrition education, social support and mindfulness training. The behavior weight loss program prescribed a diet, restricted calorie-dense foods, reinforced avoidance of cues to overeat, and focused on restricting calories. The combined program integrated the focus on diet and energy intake from the behavioral weight loss program with Regulation of Cues, including management hunger cues.

“Individuals who need help losing weight can seek out the Regulation of Cues program if behavioral weight loss did not work for them, if they feel they have trouble resisting eating, or if they never feel full,” said Boutelle.

Regulation of Cues is being offered in another randomized clinical trial called Solutions for Hunger and Regulating Eating and at the UC San Diego Center for Healthy Eating and Activity Research of which Boutelle is the director.

Co-authors include: Dawn M. Eichen, David R. Strong, Dong-Jin Eastern Kang-Sim, and Cheryl L. Rock, all with UC San Diego; Carol B, Peterson, University of Minnesota; and Bess Marcus, Brown University.

This research was funded, in part, by the National Institutes of Health (R01DK103554, UL1TR001442).

Disclosures: The authors have no conflicts of interest to disclose.

DOI: 10.1001/jamanetworkopen.2022.12354

5 mg dose of melatonin had a significant increase in total sleep time and sleep efficiency

Melatonin is one of the most used supplements in the United States. Among older adults, its use has tripled in the last two decades. But there is no consensus on the right dosage of melatonin, and studies of its effects on sleep quality in older adults have had mixed results. Researchers from Brigham and Women’s Hospital conducted a study in 24 healthy, older adults to evaluate whether a high-dose or a low-dose melatonin supplement could improve sleep. The team found that the higher dose had a significant impact, increasing total sleep time compared to placebo by more than 15 minutes for nighttime sleep and by half an hour for daytime sleep. Results are published in The Journal of Pineal Research.

“Sleep deficiency becomes more common as people age, and, given the drawbacks to many prescription sleep aids, many older adults report taking melatonin,” said senior author Charles Czeisler, PhD, MD, chief of the Brigham’s Division of Sleep and Circadian Disorders. “But we’ve had little evidence on the effects of melatonin on the sleep health of older adults. Our study provides new evidence and insight, and points to the importance of considering dosage and timing when it comes to the effects of supplements like melatonin, especially in older people.”

The body naturally produces the hormone melatonin, which helps regulate a person’s sleep-wake cycle with night and day. Melatonin levels peak at night. But among older people, levels of the hormone are often lower. Exogenous melatonin is sold over the counter and can be taken before bedtime as a dietary supplement, usually in the form of a pill or capsule.

To rigorously evaluate the effects of melatonin supplements, the study’s authors focused on healthy, older adults with no history of major sleep complaints. All potential participants were screened for sleep disorders. The study included 24 participants (13 women, 11 men) between the ages of 55 and 78.

During the month-long study period, participants lived in individual study rooms with no windows, clocks, or other indications of time of day. Participants followed a forced desynchrony protocol — instead of experiencing 24-hour cycles of days and nights, they were on schedules of 20-hour cycles to disentangle the effects of rest-activity from the circadian clock. This allowed the sleep to be scheduled both at night and during the day, but with a similar duration of waking before each sleep. Participants were randomly assigned to receive two weeks of a placebo pill and two weeks of either a low (0.3 mg) or high (5 mg) dose of melatonin 30 minutes before bedtime. Researchers used polysomnography to record brain waves, eye movement, muscle tone, and other key sleep metrics.

The team found that the low dose of melatonin did not lead to a statistically significant change in overall sleep time and that the changes that were seen were when sleep was scheduled during the biological day. Participants taking the 5 mg dose had a significant increase in total sleep time and sleep efficiency regardless of whether sleep was scheduled during the day or night.

Vegetables that thwart pollutants

 A University of Delaware researcher has discovered a way to mitigate the effect of air pollutants in our bodies by increasing daily intake of vegetables such as celery, carrots, parsnips, and parsley.

In a new article published in The Journal of Nutritional Biochemistry, Jae Kyeom Kim, assistant professor of behavioral health and nutrition, investigates how these vegetables from the apiaceous family protect the body from accumulation of acrolein, an irritant to the lungs and skin with a strong unpleasant odor, abundantly found in cigarette smoke and automobile exhaust.

Through a series of tests, Kim and his team analyzed how apiaceous vegetables, which are high in phytonutrients, mitigated acrolein-induced toxicities. The results portrayed how oxidative stress, triggered by acrolein, can be reduced and its impacts mitigated.

“Kim’s research discovered that apiaceous vegetables supported detoxification through an increase in antioxidant enzyme activity,” Trabulsi said. “The results suggest that apiaceous vegetables may provide protection against acrolein-induced damages and inflammation because in the liver, the vegetables enhance conversion of acrolein into a water-soluble acid for bodily excretion.”

The next step was to determine a reasonable dosage amount for humans. Looking forward, Kim plans to integrate human intervention trials.

“When we calculated this, we determined the actual daily calorie amount of apiaceous vegetables for humans is roughly 1 and 1/3 cups per day,” Kim said. “It doesn’t require a high intake to see a difference, and this is an achievable amount in daily life.”

Kim and his team stress the importance of implementing behavioral changes in diet as a solution to combat the buildup of toxicants derived from air pollution.

“Research has identified that it is the totality of nutrients in fruits and vegetables that support beneficial health outcomes, rather than a single nutrient,” Trabulsi said. “Focusing on a healthy whole food diet is more impactful than relying on individual supplements.”

Taking ownership of your health

A study published this month in Age and Ageing by The Japan Collaborate Cohort (JACC) Study group at Osaka University assessed the impact of modifying lifestyle behaviors on life expectancy from middle age onwards. The researchers found that adopting five or more healthy lifestyle behaviors increased life expectancy even for individuals >80 years of age and, importantly, including those with chronic conditions.

Lifespan is dependent on social factors such as socioeconomic status, policy factors such as assisted access to healthcare, and lifestyle factors like diet and exercise. The current study used a baseline survey from the JACC study, a large research project of 49,021 individuals conducted from 1988 to1990 in 45 areas of Japan. The aim was to increase knowledge about what factors contribute to death from cancer and cardiovascular disease; thus, the questionnaire included components such as diet, exercise, alcohol intake, smoking status, sleep duration, and body mass index. Points were given for each healthy behavior and the impact of modifying these lifestyle behaviors on projected lifespan was assessed.

The study continued until December 2009, by which time 8,966 individuals had died. The study’s primary author, Dr. Ryoto Sakaniwa said. “The results were very clear. A higher number of modified healthy behaviors was directly associated with great longevity for both men and women.” The lifetime gains were highest for reducing alcohol intake, not smoking, losing weight, and increasing sleep, adding up to 6 years of life for healthy 40-year-olds.

This benefit was prominent even among older individuals (80 years or more) and those with one or more major comorbidities including cancer, cardiovascular disease, hypertension, diabetes, and kidney disease, and in each life stage from middle age onwards. “This is a particularly important finding given that the prevalence of chronic disease has increased globally and is a major cause of death in older populations,” says Senior author, Prof. Hiroyasu Iso. This is one of the first studies to measure the impact of improvements to health behavior among older individuals in a country with a national life expectancy achieving almost 85 years.

The finding that lifestyle improvements has a positive impact on health despite chronic health conditions and older age is an empowering one, especially given the increasing prevalence of chronic conditions and longer life. The findings of this study will contribute to the design of future healthcare settings, public health approaches, and policies that work in partnership with patients to promote healthy lifestyle choices. 

Regular blueberry consumption may reduce risk of dementia

The old adage says that an apple a day keeps the doctor away, but new research from the University of Cincinnati shows the potential benefit of a different fruit for your health. 

Researchers led by UC’s Robert Krikorian, PhD, found that adding blueberries to the daily diets of certain middle-aged populations may lower the chances of developing late-life dementia. The findings were recently published in the journal Nutrients. 

Research approach 

Krikorian said his team has been conducting research on the benefits of berries for people with greater risk for Alzheimer’s disease and dementia for several years. 

While not entirely different from other berries and plants like red cabbage, Krikorian said blueberries have a particularly high level of micronutrients and antioxidants called anthocyanins. Anthocyanins help give blueberries their namesake color and also help defend the plants against excess radiation exposure, infectious agents and other threats, Krikorian said. 

These same properties that help blueberries survive also provide benefits to humans, Krikorian said, such as reducing inflammation, improving metabolic function and enhancing energy production within cells. 

Previous berry studies Krikorian led focused on older populations, but with this research, the team wanted to study middle-aged individuals in order to focus on dementia prevention and risk reduction. 

Krikorian explained that about 50% of individuals in the U.S. develop insulin resistance, commonly referred to as prediabetes, around middle age. Prediabetes has been shown to be a factor in chronic diseases, he said.  

“We had observed cognitive benefits with blueberries in prior studies with older adults and thought they might be effective in younger individuals with insulin resistance,” said Krikorian, professor emeritus and director of the division of psychology in the UC College of Medicine’s Department of Psychiatry and Behavioral Neuroscience. “Alzheimer’s disease, like all chronic diseases of aging, develops over a period of many years beginning in midlife.” 

Study details and results 

The researchers enrolled 33 patients from around the Cincinnati area between the ages of 50-65 who were overweight, prediabetic and had noticed mild memory decline with aging. Krikorian said this population has an increased risk for late-life dementia and other common conditions. 

Over a period of 12 weeks, the patients were asked to abstain from berry fruit consumption of any kind except for a daily packet of supplement powder to be mixed with water and consumed either with breakfast or dinner. Half of the participants received powders that contained the equivalent of one-half cup of whole blueberries, while the other half received a placebo. 

Participants were also given tests that measured certain cognitive abilities that decline in patients with aging and late-life dementia, such as executive functions like working memory, mental flexibility and self control. 

Krikorian said those in the blueberry-treated group showed improvement on cognitive tasks that depend on executive control.  

“This was evident as reduced interference of extraneous information during learning and memory,” Krikorian explained. 

Patients in the blueberry group also had lower fasting insulin levels, meaning the participants had improved metabolic function and were able to more easily burn fat for energy.  

Krikorian said the blueberry group displayed an additional mild degree of higher mitochondrial uncoupling, a cellular process that has been associated with greater longevity and reduced oxidative stress. Oxidative stress can lead to symptoms like fatigue and memory loss. 

“This last finding was exploratory but points to an interesting, potential mechanism for blueberry benefits,” he said. 

Moving forward, Krikorian said he is interested in better understanding the exact mechanisms of blueberries that help to improve cognitive performance and metabolic function. But the main takeaway from the current study is that regular blueberry supplementation into at-risk middle-aged diets may lower the chances of developing late-life dementia. 

“The sample size is an obvious limitation of the study, so it will be important to reproduce these findings, especially by other investigators,” Krikorian said. “In the meantime, it might be a good idea to consume blueberries on a regular basis.”