The Gary Null Show - 07.08.21

One year of aerobic exercise training may reduce risk of Alzheimer's in older adults

 

University of Texas Southwestern, July 6, 2021

New research suggests one year of moderate-to-vigorous intensity aerobic exercise training improved cardiorespiratory fitness, cerebral blood flow regulation, memory and executive function in people with mild cognitive impairment. The data suggest improvement in cerebrovascular function from exercise training also has the potential to reduce the risk of Alzheimer's disease in older adults, according to the research team at the University of Texas Southwestern Medical Center. The research paper is published in the Journal of Applied Physiology.

Alzheimer's disease is the most common cause of dementia, accounting for 60–80% of dementia cases, according to the Alzheimer's Association. The group estimates more than 6 million people living in the U.S. with Alzheimer's.

More facts from the Alzheimer's Association:

• Alzheimer's kills more people than breast cancer and prostate cancer combined.
• Alzheimer's deaths have increased by 16% during the COVID-19 pandemic.
• In 2021, Alzheimer's is projected to cost the nation $355 billion.

 

Credit: American Physiological Society

In this new study, the research team observed 37 people with mild cognitive impairment, which is a precursor stage of Alzheimer's disease. At the beginning of the study, the subjects participated in three exercise sessions per week that consisted of brisk walking for 25–30 minutes. By week 11, they exercised four times a week, walking briskly uphill for 30–35 minutes per session. After week 26, exercise sessions increased to four to five times per week for 30–40 minutes.

Using these findings as a building block, a new two-year study is underway to determine the long-term impact of aerobic exercise on Alzheimer's disease, according to Tsubasa Tomoto, Ph.D., a member of the research team. The researchers' goal is to turn the findings of both studies into more practical ways to mitigate the risk of the disease.

 

Review finds intake of probiotics improves numerous factors in people with colorectal cancer

University of Malaya (Malaysia), June 30, 2021

A systematic review of randomized trials that appeared on May 24, 2021 in Nutrition Reviews concluded that probiotic intake is associated with a number of beneficial effects in colorectal cancer (CRC) patients with any stage of the disease.

Probiotics are living microorganisms (typically bacteria, but also yeasts such as Saccharomyces spp.) that when consumed in adequate amounts have been shown to benefit the health of the body. Consuming probiotics may benefit gut health, nutritional status, immune function and even brain health. Prebiotics are foods (often non-digestible oligosaccharides such as xylooligosaccharides) that nourish probiotics and the healthy bacteria in the gut and support their maintenance within the body. 

For their review, researchers at the University of Malaya in Kuala Lumpur, Malaysia screened numerous databases, finding 23 randomized, controlled trials that met the criteria for their review. The studies included a total of 2,457 participants who had undergone surgery for various stages of CRC. A total of 1,403 participants received probiotics and 1,054 participants served as controls. 

Of the included studies, 12 trials evaluated the effects of a mixture of probiotics, 7 trials used synbiotics (which combine prebiotics with probiotics), 3 trials used single strains of probiotics and 1 trial used the fermented milk beverage kefir. The probiotics most commonly administered included Bifidobacteria and Lactobacillus varieties. Six of the included trials analyzed the effects of probiotics on gut microbiota, 4 trials studied their effects on the immune system and inflammatory biomarkers, 18 examined postoperative complications, 7 evaluated length of hospital stay, 4 measured quality of life improvement, 2 assessed tumor growth and tumor stage development, and mortality was assessed in two trials. 

The researchers found probiotics improved gut microbiota diversity, and in one study also reduced amounts of a bacteria shown to be present at higher levels in patients with CRC. In multiple studies, there were fewer postoperative infection complications, less proinflammatory cytokine production and better quality of life occurred among participants who took probiotics compared to the control groups. Probiotic intake was also found to decrease chemotherapy side effects, decrease tumor growth, improve surgery outcomes, shorten hospital stay and lower risk of mortality.  

“The use of probiotics and synbiotics provides numerous health benefits, as seen in this systematic review,” the authors wrote. “The findings in this systematic review also highlight the importance of preoperative administration of probiotics or synbiotics as well as postoperative administration of probiotics, especially for patients with colorectal cancer who have invasive surgeries and are on a chemotherapy regimen.”

In closing, they note “In the future, the use of probiotics against colorectal cancer should be able to broaden and become more personalized in treatment of patients with colorectal cancer. Dietitians, nutritionists, and general practitioners should also recommend intake of probiotic[s]…more frequently to reduce the risk of colorectal cancer development, and the administration of probiotics should commence at the first diagnosis of colon polyps.”

 

 

 

 

Study finds time-restricted eating may reduce diabetes-related hypertension

 

University of Kentucky College of Medicine, July 2, 2021

A new University of Kentucky College of Medicine study suggests that time-restricted eating may be able to help people with Type 2 diabetes reduce nocturnal hypertension, which is characterized by elevated blood pressure at night.

The study published in PNAS June 22 found that time-restricted eating, a routine in which eating is restricted to a specific window of time during each day, helped prevent and improve diabetes-related nocturnal hypertension in mice.

Study authors Ming Gong, Ph.D., M.D., professor in the Department of Physiology, and Zhenheng Guo, Ph.D., professor in the Department of Pharmacology and Nutritional Sciences, are hopeful their findings will mean time-restricted eating could offer similar benefits for people.

"We are excited about these findings and the implications they could have in future clinical studies," said Guo. "In addition to lifestyle changes like diet and exercise, time-restricted eating could have a healthy impact on people with Type 2 diabetes."

Normally, blood pressure falls at night and increases upon awakening, in line with the body's circadian rhythm. In some hypertensive patients, the typical nighttime decrease does not occur. This "nondipping" blood pressure is prevalent in patients with Type 2 diabetes and is associated with increased events of cardiovascular disease.

The study found that imposing time-restricted feeding prevented diabetic mice from developing nondipping blood pressure. The practice also effectively restored the disrupted blood pressure circadian rhythm in mice that already had nondipping blood pressure.

Researchers restricted the mice's access to food to eight hours during their typical active awake times every day. When food availability was increased to 12 hours, the practice was still effective in preventing and treating nondipping blood pressure. Guo says this is evidence that the effects were caused by the timing of feeding and not calorie restriction.

In addition to the study's significance for future clinical research in people, Gong says it's adding to scientists' understanding of the causes and mechanisms of nondipping blood pressure in diabetes, which is currently not fully understood.

"There are already many studies that show the health benefits of time-restricted eating, particularly for metabolic issues," Gong said. "This is the first basic science research focused on how it impacts nondipping blood pressure related to diabetes and it reveals that the daily timing of food intake could play a critical role."

 

Vitamin D deficiency associated with higher blood pressure and impaired serum lipid profiles

Urmia University of Medical Sciences (Iran), July 1, 2021

According to news reporting out of Urmia University of Medical Sciences by NewsRx editors, research stated, “Hypertension is one of the leading causes of mortality in the world. The aim of this study was to evaluate the relationship of plasma 25-hydroxyvitamin D levels with markers of metabolic syndrome and ambulatory blood pressure monitoring.”

Our news journalists obtained a quote from the research from Urmia University of Medical Sciences: “This was a cross-sectional study on 171 adults (79 men) with primary hypertension and mean age of 50.70 ± 10.88 years, who did not take vitamin D supplement for the past 6 months. Subjects were divided into two groups as deficient (30 ng/ml ) and normal levels of vitamin D (30 ng/ml <) and compared for metabolic syndrome indices and 24-hour blood pressure monitoring parameters. Hypertension was defined based on Eighth Joint National Committee (JNC8) scale, and measured by an ambulatory blood pressure monitoring device. Ambulatory blood pressure monitoring parameters were defined as 24-hour blood pressure (mean during 24 hours), daytime (6-23 hours), and nighttime (23-6 hours) measurements. The mean vitamin D level was 30.43 ± 4.70 ng/ml, and 65.5% of patients had vitamin D deficiency. Serum vitamin D levels had an inverse and significant relationship with office systolic blood pressure (P = 0.001), and 24-hour, daytime, and nighttime systolic blood pressures (P < 0.001). Vitamin D deficiency was significantly associated with higher levels of triglycerides (P < 0.001) and cholesterol (P = 0.016).”

According to the news reporters, the research concluded: “Vitamin D deficiency was associated with higher systolic blood pressure, nighttime diastolic blood pressure, and impaired serum lipid profiles.”

 

 

Mindfulness training helps kids sleep better, Stanford Medicine study finds

Stanford University, July 6, 2021

At-risk children gained more than an hour of sleep per night after participating in a mindfulness curriculum at their elementary schools, a study from the Stanford University School of Medicine found.

The research will be published online July 6 in the Journal of Clinical Sleep Medicine. The study is the first to use polysomnography techniques, which measure brain activity, to assess how school-based mindfulness training changes children's sleep. The curriculum taught children how to relax and manage stress by focusing their attention on the present, but it did not instruct them on how to get more sleep.

"The children who received the curriculum slept, on average, 74 minutes more per night than they had before the intervention," said the study's senior author, Ruth O'Hara, PhD, a sleep expert and professor of psychiatry and behavioral sciences at Stanford. "That's a huge change." 

Rapid eye movement sleep, which includes dreaming and helps consolidate memories, also lengthened in children who learned the techniques.

"They gained almost a half an hour of REM sleep," said O'Hara, the Lowell W. and Josephine Q. Berry Professor. "That's really quite striking. There is theoretical, animal and human evidence to suggest it's a very important phase of sleep for neuronal development and for the development of cognitive and emotional function."

Helping at-risk kids sleep better

Children in the study lived in two low-income, primarily Hispanic communities in the San Francisco Bay Area. One community received the intervention; the other served as the control. Both had high rates of crime and violence, and families faced such stressors as food insecurity and crowded, unstable housing. These conditions are a recipe for poor sleep, said the study's principal investigator, Victor Carrion, MD, the John A. Turner, MD, Endowed Professor for Child and Adolescent Psychiatry. Carrion, who directs the Stanford Early Life Stress and Resilience Program, launched the study to help youngsters manage the effects of living in a stressful environment. 

Enabling at-risk kids to sleep better isn't just a matter of telling them to sleep more or keep regular bedtimes, however.

"To fall asleep you have to relax, but they have a hard time letting their experiences go," Carrion said. "They don't feel safe and may have nightmares and fears at night."

The study curriculum consisted of training in bringing one's attention to the present; exercises featuring slow, deep breathing; and yoga-based movement. Yoga instructors and the children's classroom teachers taught the curriculum twice a week, for two years, in all elementary and middle schools in the community that received the intervention. Instructors taught children what stress was and encouraged them to use the techniques to help them rest and relax, but they did not give any instruction on sleep-improvement techniques such as maintaining consistent bedtimes. 

The instructors used the Pure Power Curriculum, developed by a nonprofit called PureEdge; it is available to schools for free in both Spanish and English.

From the more than 1,000 third- and fifth-graders taking part in the study, the researchers recruited 58 children who received the curriculum and 57 children from the control group for three in-home sleep assessments, conducted before the curriculum began, after one year and after two years. These assessments measured brain activity during sleep, via a cap of electrodes placed on the child's head, as well as breathing and heart rates and blood oxygen levels.

More sleep instead of less

At the start of the study, researchers found that children in the control group slept 54 minutes more, on average, and had 15 minutes more REM sleep per night than children in the group that later received the training: Children in the control group were sleeping about 7.5 hours per night, and those in the curriculum group about 6.6 hours per night. The researchers don't know why children in the two communities, despite similarities in income level and other demographics, had different average sleep times.

But the two group's sleep patterns evolved differently. Over the two-year study period, among the children in the control group, total sleep declined by 63 minutes per night while the minutes of REM sleep remained steady, in line with sleep reductions typically seen in later childhood and early adolescence. In contrast, the children who participated in the curriculum gained 74 minutes of total sleep and 24 minutes of REM sleep.

"It makes intuitive sense that children who didn't participate in the curriculum decreased their sleep, based on what we know about what it's like to be a kid this age," said the study's lead author, Christina Chick, PhD, postdoctoral scholar in psychiatry and behavioral sciences. "Older children are possibly staying up to do homework or talk or text with friends. I interpret our findings to mean that the curriculum was protective, in that it taught skills that helped protect against those sleep losses." Hormonal changes and brain development also contribute to changes in sleep at this age, Chick noted.

Still, the average amount of sleep that study participants in both groups received was low, Chick said, noting that at least nine hours of sleep per night is recommended for healthy children.

The researchers hypothesized that children might experience improvements in sleep via reductions in stress. However, the children who gained the most sleep during the study also reported increases in stress, perhaps because the curriculum helped them understand what stress was. Nevertheless, they slept better.

The researchers plan to disseminate the findings more broadly, such as by helping schoolteachers deliver a similar curriculum. They also plan further studies to understand how various elements of the curriculum, such as exercises that promote deep, slow breathing, may change body functioning to enable better sleep. 

"We think the breath work changes the physiological environment, perhaps increasing parasympathetic nervous system activity, and that actually results in improved sleep," Chick said.

 

Food based carotenoids may lower lung cancer risk: Study

Montreal University, July 4, 2021

People consuming the highest intakes of carotenoids and vitamin C from fruit and vegetable sources may reduce their risk of lung cancer by 25%-35%, suggests a study in Frontiers in Oncology.

The research team from Montreal University also found that smokers, particularly males, who consume high quantities of fruit and vegetables, also reduce their risk.

“In our study, high dietary intakes of β-carotene, α-carotene, β-cryptoxanthin, lycopene, and vitamin C were associated with a decreased risk of lung cancer,” wrote Martine Shareck, lead author.

The risk reductions of 25-35% were irrespective of age, gender or smoking status.

Gender effect in smokers

When results were analysed by different levels of smoking history, the protective effects were more gender specific.  

“Odds ratios (OR) suggestive of a protective effect were found for elevated intakes of β-carotene, α-carotene, β-cryptoxanthin, and lycopene in male heavy smokers,” noted the team.

By contrast, only vitamin C provided a significant benefit in female heavy smokers.  

Nevertheless, β-carotene, β-cryptoxanthin and lycopene indicated protection in female moderate smokers.

For the two latter carotenoids, statistical significance was only reached for the middle tertile of carotenoid intake, rather than the highest.

Study details

Using data from a case control study of lung cancer, scientists examined the relationship between intakes of dietary carotenoids and vitamin C with lung cancer risk.

They calculated carotenoid intakes using food frequency questionnaires of participants’ fruit and vegetable consumption during the previous two years.

Intakes were divided into tertiles, and the risk reductions of 25%-35% compare upper versus lower tertile intakes.

The study also found a link between higher carotenoid intake and decreased cell development in different subtypes of cancer.  

Beta-carotene, α-carotene, ß-cryptoxanthin, lycopene and vitamin C were inversely related to progression of squamous cell carcinoma.

Alpha-carotene and ß-carotene slowed adenocarcinoma cell growth, while ß-cryptoxanthin and lycopene show inverse associations with small cell carcinoma development.

Contrasting findings

The findings contrasted with two previous large randomised controlled trials, the Beta-Carotene and Retinol Efficacy Trial (CARET) , and the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study.

Both concluded that β-carotene supplementation increased lung cancer risk in smokers, particularly females, with the latter recommending, “Smokers should avoid β-carotene supplementation.”

The researchers suggested that contrasting results could be because carotenoids in this study were from dietary fruit and vegetable consumption whereas in the CARET and ATBC trials they were supplement based.

“Fruits and vegetables containing carotenoids and vitamin C are also rich in other nutrients and phytochemicals which could be responsible for their observed protective role against lung cancer.”

In conclusion, they added, “even though smoking remains the strongest predictor of lung cancer risk, it appears desirable, in light of these findings, to further promote consumption of fruits and vegetables rich in carotenoids and vitamin C to reduce the lung cancer burden among both smokers and non-smokers.”

Source: Frontiers in Oncology

 

 

 

Low choline intake associated with risk of osteoporosis In elderly individuals

Southeast University (China), July 1, 2021

According to news reporting originating in Jiangsu, People’s Republic of China, research stated, “Currently, little is known regarding the association between dietary choline intake and osteoporosis in elderly individuals, as well as if such intakes affect bone health and result in fractures. This study was aimed to examine associations between daily dietary choline intake and osteoporosis in elderly individuals.”

The news reporters obtained a quote from the research from Southeast University, “A total of 31 034 participants from the National Health and Nutritional Examination Survey (NHANES) during 2005-2010 were enrolled, and 3179 participants with complete data and aged 65 years and older were identified. Baseline characteristics and dietary intake data were obtained through method of in-home administered questionnaires. Of 3179 individuals with a mean age of 73.7 +/- 5.6 years, female (P < 0.001) and non-hispanic white (P < 0.001) occupied a higher proportion in the osteoporosis group. The logistic regression analysis indicated that the prevalence of osteoporosis in three tertile categories with gradually enhanced dietary choline intake was decreased progressively (P for trend <0.001). The restricted cubic spline (RCS) showed that the risk of osteoporosis generally decreased with increasing daily dietary choline intake (P < 0.001), while this trend was not apparent in relation between the daily dietary choline intake and risk of hip fracture (P = 0.592). The receiver operating characteristic (ROC) analysis identified a daily dietary choline intake of 232.1 mg as the optimal cutoff value for predicting osteoporosis.”

According to the news reporters, the research concluded: “Our nationwide data suggested that a lower level of daily dietary choline intake was positively associated with the increased risk of osteoporosis in the US elderly population.”

This research has been peer-reviewed.