Gary Null Show Notes 02/08/21
The Acute and Chronic Cognitive Effects of a Sage Extract: A Randomized, Placebo Controlled Study in Healthy Humans
Northumbria University (UK), January 31, 2021
The sage (Salvia) plant contains a host of terpenes and phenolics which interact with mechanisms pertinent to brain function and improve aspects of cognitive performance. However, previous studies in humans have looked at these phytochemicals in isolation and following acute consumption only. A preclinical in vivo study in rodents, however, has demonstrated improved cognitive outcomes following 2-week consumption of CogniviaTM, a proprietary extract of both Salvia officinalis polyphenols and Salvia lavandulaefolia terpenoids, suggesting that a combination of phytochemicals from sage might be more efficacious over a longer period of time. The current study investigated the impact of this sage combination on cognitive functions in humans with acute and chronic outcomes. Participants (n = 94, 25 M, 69 F, 30–60 years old) took part in this randomised, double-blind, placebo-controlled, parallel groups design where a comprehensive array of cognitions were assessed 120- and 240-min post-dose acutely and following 29-day supplementation with either 600 mg of the sage combination or placebo. A consistent, significant benefit of the sage combination was observed throughout working memory and accuracy task outcome measures (specifically on the Corsi Blocks, Numeric Working Memory, and Name to Face Recall tasks) both acutely (i.e., changes within day 1 and day 29) and chronically (i.e., changes between day 1 to day 29). These results fall slightly outside of those reported previously with single Salvia administration, and therefore, a follow-up study with the single and combined extracts is required to confirm how these effects differ within the same cohort.
In conclusion, we have observed a consistent significant benefit of a sage combination intervention in healthy adult humans on working memory and accuracy of performance cognitive domains. This significant activity was observed both acutely (after just 2 h following consumption) and chronically (after 29 days of administration). The pattern and magnitude of significance points towards an increase in product efficacy over the administration period and, taken together, suggests that future trials should focus on disentangling the working and spatial memory effects of this intervention in humans with an extended timeframe of perhaps several months. Validating the CaMKII mechanism in humans would also be advantageous.
Blink! The link between aerobic fitness and cognition
University of Tsukuba (Japan), February 3, 2021
Although exercise is known to enhance cognitive function and improve mental health, the neurological mechanisms of this link are unknown. Now, researchers from Japan have found evidence of the missing link between aerobic fitness and cognitive function.
In a study published in Medicine & Science in Sports & Exercise, researchers from the University of Tsukuba revealed that spontaneous eye blink rate (sEBR), which reflects activity of the dopamine system, could be used to understand the connection between cognitive function and aerobic fitness.
The dopaminergic system is known to be involved in physical activity and exercise, and previous researchers have proposed that exercise-induced changes in cognitive function might be mediated by activity in the dopaminergic system. However, a marker of activity in this system was needed to test this hypothesis, something the researchers at the University of Tsukuba aimed to address.
“The dopaminergic system is associated with both executive function and motivated behavior, including physical activity,” says first author of the study Ryuta Kuwamizu. “We used sEBR as a non-invasive measure of dopaminergic system function to test whether it could be the missing link between aerobic fitness and cognitive function.”
To do this, the researchers asked healthy participants to undergo a measure of sEBR, a test of cognitive function, and an aerobic fitness test. They also measured brain activity during the cognitive task using functional near-infrared spectroscopy.
“As expected, we found significant correlations between aerobic fitness, cognitive function, and sEBR,” explains Professor Hideaki Soya, senior author. “When we examined these relationships further, we found that the connection between higher aerobic fitness and enhanced cognitive function was mediated in part by dopaminergic regulation.”
Furthermore, activity in the left dorsolateral prefrontal cortex (l-DLPFC) during the cognitive task was the same or lower in participants with higher sEBR compared with lower sEBR, even though those with higher sEBR appeared to have greater executive function, and thus higher neural efficiency.
“Although previous studies have indicated that aerobic fitness and cognitive function are correlated, this is the first to provide a neuromodulatory basis for this connection in humans. Our data indicate that dopamine has an essential role in linking aerobic fitness and cognition,” says first author Kuwamizu.
Given that neural efficiency in the l-DLPFC is a known characteristic of the dopaminergic system that has been observed in individuals with higher fitness and executive function, it is possible that neural efficiency in this region partially mediates the association between aerobic fitness and executive function. Furthermore, physical inactivity may be related to dopaminergic dysfunction. This information provides new directions for research regarding how fitness affects the brain, which may lead to improved exercise regimens. For instance, exercise that specifically focuses on improving dopaminergic function may particularly boost motivation, mood, and mental function.
Vegan diet better for weight loss and cholesterol control than Mediterranean diet
Physicians Committee for Responsible Medicine, February 5, 2021
A vegan diet is more effective for weight loss than a Mediterranean diet, according to a groundbreaking new study that compared the diets head to head. The randomized crossover trial, which was published in the Journal of the American College of Nutrition, found that a low-fat vegan diet has better outcomes for weight, body composition, insulin sensitivity, and cholesterol levels, compared with a Mediterranean diet.
The study randomly assigned participants–who were overweight and had no history of diabetes–to a vegan diet or a Mediterranean diet in a 1:1 ratio. For 16 weeks, half of the participants started with a low-fat vegan diet that eliminated animal products and focused on fruits, vegetables, whole grains, and legumes. The other half started with the Mediterranean diet, which followed the PREDIMED protocol, which focuses on fruits, vegetables, legumes, fish, low-fat dairy, and extra virgin olive oil, while limiting or avoiding red meat and saturated fats. Neither group had a calorie limit, and participants did not change exercise or medication routines, unless directed by their personal doctors. As part of the crossover design, participants then went back to their baseline diets for a four-week washout period before switching to the opposite group for an additional 16 weeks.
The study found that within 16 weeks on each diet:
- Participants lost an average of 6 kilograms (or about 13 pounds) on the vegan diet, compared with no mean change on the Mediterranean diet.
- Participants lost 3.4 kg (about 7.5 pounds) more fat mass on the vegan diet.
- Participants saw a greater reduction in visceral fat by 315 cm3 on the vegan diet.
- The vegan diet decreased total and LDL cholesterol levels by 18.7 mg/dL and 15.3 mg/dL, respectively, while there were no significant cholesterol changes on the Mediterranean diet.
- Blood pressure decreased on both diets, but more on the Mediterranean diet (6.0 mm Hg, compared to 3.2 mmHg on the vegan diet).
“Previous studies have suggested that both Mediterranean and vegan diets improve body weight and cardiometabolic risk factors, but until now, their relative efficacy had not been compared in a randomized trial,” says study author Hana Kahleova, MD, PhD, director of clinical research for the Physicians Committee. “We decided to test the diets head to head and found that a vegan diet is more effective for both improving health markers and boosting weight loss.”
The authors note that the vegan diet likely led to weight loss, because it was associated with a reduction in calorie intake, increase in fiber intake, decrease in fat consumption, and decrease in saturated fat consumption.
“While many people think of the Mediterranean diet as one of the best ways to lose weight, the diet actually crashed and burned when we put it to the test,” says study author Neal Barnard, MD, president of the Physicians Committee. “In a randomized, controlled trial, the Mediterranean diet caused no weight loss at all. The problem seems to be the inclusion of fatty fish, dairy products, and oils. In contrast, a low-fat vegan diet caused significant and consistent weight loss.”
“If your goal is to lose weight or get healthy in 2021, choosing a plant-based diet is a great way to achieve your resolution,” adds Dr. Kahleova.
Study finds childhood diet has lifelong impact
University of California at Riverside, February 3, 2021
Eating too much fat and sugar as a child can alter your microbiome for life, even if you later learn to eat healthier, a new study in mice suggests.
The study by UC Riverside researchers is one of the first to show a significant decrease in the total number and diversity of gut bacteria in mature mice fed an unhealthy diet as juveniles.
“We studied mice, but the effect we observed is equivalent to kids having a Western diet, high in fat and sugar and their gut microbiome still being affected up to six years after puberty,” explained UCR evolutionary physiologist Theodore Garland.
A paper describing the study has recently been published in the Journal of Experimental Biology.
The microbiome refers to all the bacteria as well as fungi, parasites, and viruses that live on and inside a human or animal. Most of these microorganisms are found in the intestines, and most of them are helpful, stimulating the immune system, breaking down food and helping synthesize key vitamins.
In a healthy body, there is a balance of pathogenic and beneficial organisms. However, if the balance is disturbed, either through the use of antibiotics, illness, or unhealthy diet, the body could become susceptible to disease.
In this study, Garland’s team looked for impacts on the microbiome after dividing their mice into four groups: half fed the standard, ‘healthy’ diet, half fed the less healthy ‘Western’ diet, half with access to a running wheel for exercise, and half without.
After three weeks spent on these diets, all mice were returned to a standard diet and no exercise, which is normally how mice are kept in a laboratory. At the 14-week mark, the team examined the diversity and abundance of bacteria in the animals.
They found that the quantity of bacteria such as Muribaculum intestinale was significantly reduced in the Western diet group. This type of bacteria is involved in carbohydrate metabolism.
Analysis also showed that the gut bacteria are sensitive to the amount of exercise the mice got. Muribaculum bacteria increased in mice fed a standard diet who had access to a running wheel and decreased in mice on a high-fat diet whether they had exercise or not.
Researchers believe this species of bacteria, and the family of bacteria that it belongs to, might influence the amount of energy available to its host. Research continues into other functions that this type of bacteria may have.
One other effect of note was the increase in a highly similar bacteria species that were enriched after five weeks of treadmill training in a study by other researchers, suggesting that exercise alone may increase its presence.
Overall, the UCR researchers found that early-life Western diet had more long-lasting effects on the microbiome than did early-life exercise.
Garland’s team would like to repeat this experiment and take samples at additional points in time, to better understand when the changes in mouse microbiomes first appear, and whether they extend into even later phases of life.
Regardless of when the effects first appear, however, the researchers say it’s significant that they were observed so long after changing the diet, and then changing it back.
The takeaway, Garland said, is essentially, “You are not only what you eat, but what you ate as a child!”
Turns Out Maple Syrup Is Anticarcinogenic
Kindai University (Japan), February 2, 2021
Darker coloured syrup is suggested as healthier than lightly coloured syrup.
Maple syrup is a classic natural sweetener that has been making a comeback recently as an alternative to refined sugar. The syrup is tapped from different species of maple trees, with the Canadian province of Quebec being a top producer. Along with a rich and complex flavor, maple syrup offers an abundance of amino acids, manganese and zinc, as well as phenolic compounds, including lignans and coumarin.
A new study called “Inhibitory effect of maple syrup on the cell growth and invasion of human colorectal cancer cells” was guided by Dr. Tetsushi Yamamoto, a molecular and cell biologist from the Faculty of Pharmacy at Kindai University in Osaka, Japan. The research evaluated the effect of three different types of maple syrup. The main objective was to identify if maple syrup could be used as a phytomedicine within cancer treatment.
Dr. Yamamoto and his research team classified the different types of maple syrup according to colour, as well as cell proliferation, and migration and invasion capability for colorectal cell cancer (CRC). Results showed that CRC cells administered maple syrup showed lower rates of carcinogenic cells when compared with cells administered only sucrose.
Additionally, the study suggests that maple syrup should not only be classified by its sugar content, but also according to its nutritional and physiochemical components. This study showed that maple syrup, particularly when coloured darker, might be suitable as a phytomedicine, which may offer a more gentle alternative to traditional chemotherapy.
This outstanding revelation is in contrast to other studies, which support the idea that sugar perpetuates cancer and other chronic diseases. However, this disparity might concern diverse types of sugar, including sucrose, fructose and glucose. Also, sugar behaves differently when consumed in diverse nutritional contexts.
In this context, researchers experimented with different sucrose concentrations, ranging from 0.1% to 10%. Results showed that only maple syrup with a 10% concentration of sucrose inhibited colorectal cancer cell growth. The study explained that this is because higher concentrations might have cytotoxic effects due to high osmotic pressure.
Brains are more plastic than we thought
McGill University, January 31, 2021
Practice might not always make perfect, but it’s essential for learning a sport or a musical instrument. It’s also the basis of brain training, an approach that holds potential as a non-invasive therapy to overcome disabilities caused by neurological disease or trauma.
Research at the Montreal Neurological Institute and Hospital of McGill University (The Neuro) has shown just how adaptive the brain can be, knowledge that could one day be applied to recovery from conditions such as stroke.
Researchers Dave Liu and Christopher Pack have demonstrated that practice can change the way that the brain uses sensory information. In particular, they showed that, depending on the type of training done beforehand, a part of the brain called the area middle temporal (MT) can be either critical for visual perception, or not important at all.
Previous research has shown the area MT is involved in visual motion perception. Damage to area MT causes “motion blindness”, in which patients have clear vision for stationary objects but are unable to see motion. Such deficits are somewhat mysterious, because it is well known that area MT is just one of many brain regions involved in visual motion perception. This suggests that other pathways might be able to compensate in the absence of area MT.
Most studies have examined the function of area MT using a task in which subjects view small dots moving across a screen and indicate how they see the dots moving, because this has been proven to activate area MT. To determine how crucial MT really was for this task, Liu and Pack used a simple trick: They replaced the moving dots with moving lines, which are known to stimulate areas outside area MT more effectively. Surprisingly, subjects who practiced this task were able to perceive visual motion perfectly even when area MT was temporarily inactivated.
On the other hand, subjects who practiced with moving dots exhibited motion blindness when MT was temporarily deactivated. The motion blindness persisted even when the stimulus was switched back to the moving lines, indicating that the effects of practice were very difficult to undo. Indeed, the effects of practice with the moving dot stimuli were detectable for weeks afterwards. The key lesson for brain training is that small differences in the training regimen can lead to profoundly different changes in the brain.
This has potential for future clinical use. Stroke patients, for example, often lose their vision as a result of brain damage caused by lack of blood flow to brain cells. With the correct training stimulus, one day these patients could retrain their brains to use different regions for vision that were not damaged by the stroke.
“Years of basic research have given us a fairly detailed picture of the parts of the brain responsible for vision,” says Christopher Pack, the paper’s senior author. “Individual parts of the cortex are exquisitely sensitive to specific visual features – colors, lines, shapes, motion – so it’s exciting that we might be able to build this knowledge into protocols that aim to increase or decrease the involvement of different brain regions in conscious visual perception, according to the needs of the subject. This is something we’re starting to work on now.”
Higher Fiber Intake May Improve Lung Function
University of Nebraska, January 28, 2021
Eating a fiber-rich diet may help protect you against lung disease, a new study suggests.
“Lung disease is an important public health problem, so it’s important to identify modifiable risk factors for prevention,” study author Corrine Hanson, an associate professor of medical nutrition at the University of Nebraska Medical Center, said in a journal news release.
“However, beyond smoking very few preventative strategies have been identified. Increasing fiber intake may be a practical and effective way for people to have an impact on their risk of lung disease,” she added.
The findings were published recently in the Annals of the American Thoracic Society.
Researchers looked at federal government data from almost 2,000 American adults. They were between 40 and 79 years old.
The researchers found that 68 percent of those who had the highest fiber consumption (about 18 grams or more daily) had normal lung function compared to 50 percent for those with the lowest fiber intake. And, only 15 percent of those who ate a lot of fiber had airway restriction, but 30 percent of those with the lowest fiber intake did, the study showed.
People with the highest fiber consumption also did better on two important breathing tests. They had larger lung capacity and could exhale more air in one second, the study said.
Although the study found a link between fiber consumption and better lung health, it wasn’t designed to prove a cause-and-effect relationship.
But, if the findings are confirmed in future studies, public health campaigns may one day “target diet and fiber as safe and inexpensive ways of preventing lung disease,” Hanson said.
Previous research has suggested a diet high in fiber protects against heart disease and diabetes, and that fiber reduces inflammation in the body, the researchers said.