Ascorbic acid supplementation and immune response in healthy women during high-intensity exercise

 

The benefits of taking extra Ascorbic Acid (AA) while exercising are not well known.

This study aims to investigate the effects of AA supplementation on oxidative stress, immune response, and inflammation in healthy women after a single session of high-intensity exercise.

In a crossover design, 20 sedentary women (aged 18-22) participated in 30 minutes of vigorous cycling. They were split into two groups: one group received a daily supplement of 1,000 mg of ascorbic acid (1,000AA), while the other group did not receive any supplementation (0AA). This regimen was followed for one week. Blood samples were taken before exercise, immediately after exercise, and 24 hours after exercise to analyze oxidative stress, inflammatory markers, CD4+ and CD8+ lymphocytes, and neutrophil phagocytic activity.  

The AA supplement significantly increased plasma AA levels (p<0.05) and reduced post-exercise plasma MDA levels (p<0.05) but did not affect creatine kinase activity. White blood cells, CD8+ T cells, and IL-6 levels significantly increased after exercise but did not change in the 1,000AA group compared to the 0AA group. The neutrophil count increased (p<0.05) after exercise with no change in phagocytic function, although there was a slight drop in phagocytic function 24 hours after exercise in the 1,000AA group. Exercise and AA supplements had no effect on CD4+ T cells.

A single session of high-intensity exercise caused oxidative stress, muscle injury, inflammation, and a temporary increase in CD8+ T cells. Short-term AA supplementation reduced exercise-induced oxidative stress and inflammation by limiting the increase in IL-6 and CD8+ T cells.

Planetary Health Diet associated with lower risk of premature death

 

Key takeaways:

• People whose diets most closely adhered to the Planetary Health Diet (PHD) had 30% lower risk of premature death compared to those with the lowest adherence.
• Every major cause of death, including cancer, heart disease, and lung disease, was lower with greater adherence to this dietary pattern.
• Diets adhering to the PHD pattern had substantially lower environmental impact, including 29% lower greenhouse gas emissions and 51% less land use. 

People who eat a healthy, sustainable diet may substantially lower their risk of premature death in addition to their environmental impact, according to a new study led by Harvard T.H. Chan School of Public Health. It is the first large study to directly evaluate the impacts of adherence to recommendations in the landmark 2019 EAT-Lancet report. The researchers have named the dietary pattern outlined in the report—which emphasizes a variety of minimally processed plant foods but allows for modest consumption of meat and dairy foods—the Planetary Health Diet (PHD).

The study will be published online June 10 in The American Journal of Clinical Nutrition.

“Climate change has our planet on track for ecological disaster, and our food system plays a major role,” said corresponding author Walter Willett, professor of epidemiology and nutrition. “Shifting how we eat can help slow the process of climate change. And what’s healthiest for the planet is also healthiest for humans.”

While other studies have found that diets emphasizing plant-based foods over animal-sourced foods could have benefits for human and planetary health, most have used one-time dietary assessments, which produce weaker results than looking at diets over a long period of time.

The researchers used health data from more than 200,000 women and men enrolled in the Nurses’ Health Study I and II and the Health Professionals Follow-Up Study. Participants were free of major chronic diseases at the start of the study and completed dietary questionnaires every four years for up to 34 years. Participants’ diets were scored based on intake of 15 food groups—including whole grains, vegetables, poultry, and nuts—to quantify adherence to the PHD. 

The study found that the risk of premature death was 30% lower in the top 10% of participants most closely adhering to PHD compared to those in the lowest 10%. Every major cause of death, including cancer, heart disease, and lung disease, was lower with greater adherence to this dietary pattern.

In addition, the researchers found that those with the highest adherence to the PHD had a substantially lower environmental impact than those with the lowest adherence, including 29% lower greenhouse gas emissions, 21% lower fertilizer needs, and 51% lower cropland use. 

The researchers noted that land use reduction is particularly important as a facilitator of re-forestation, which is seen as an effective way to further reduce levels of greenhouse gases that are driving climate change.  

“Our study is noteworthy given that the U.S. Department of Agriculture has refused to consider the environmental impacts of dietary choices, and any reference to the environmental effects of diet will not be allowed in the upcoming revision of the U.S. Dietary Guidelines,” said Willett. “The findings show just how linked human and planetary health are. Eating healthfully boosts environmental sustainability—which in turn is essential for the health and wellbeing of every person on earth.”

Beetroot juice promotes healthy circulation in postmenopausal women

After women go through menopause, their risk of heart disease increases dramatically. To improve and support heart and blood vessel health among postmenopausal women, researchers at Penn State studied whether beetroot juice can improve how blood vessels function. Results published today (June 10) in Frontiers in Nutrition indicated that daily consumption of beetroot juice by postmenopausal women may improve blood vessel function enough to reduce future heart disease risk.

Beetroot juice contains high levels of nitrate, which the body converts to nitric oxide. Nitric oxide helps blood vessels expand, making it easier for blood to flow through the circulatory system. The ability of nitric oxide to widen blood vessels is known to be particularly helpful during periods of limited blood flow and oxygen delivery, such as during a heart attack, according to the researchers.

David Proctor, professor of kinesiology and physiology at Penn State, and Jocelyn Delgado Spicuzza, who earned her doctorate in integrative and biomedical physiology from Penn State in May, led an interdisciplinary team of researchers who tested how nitrate-rich beetroot juice impacted blood vessel health in 24 postmenopausal women in their 50s and 60s.

“After menopause, women no longer produce estrogen, which helps maintain nitric oxide in the body,” said Delgado Spicuzza, first author of the research and current SAFE-T center research project manager. “This loss of nitric oxide production contributes to the substantial increase in heart disease risk for postmenopausal women. Foods that are rich in nitrate — especially beets — are being investigated as a natural, non-pharmaceutical way to protect the heart and blood vessels.”

Nitrate is an approved food additive for some animal-based food products, such as processed meats. However, nitrate food additives and preservatives are strictly regulated due to their potential to cause cancer, according to Delgado Spicuzza. In contrast, plants like beets, spinach and lettuce naturally accumulate nitrate from the soil. These plant-based sources of nitrate have cardiovascular benefits because the human body can convert nitrates from plants to nitric oxide, which it cannot do with nitrate added to meats.

In this study, participants had their vascular function tested at the Penn State Clinical Research Center and then consumed two 2.3-ounce bottles of beetroot juice as an initial dose, followed by one bottle every morning for a week. All participants consumed concentrated beetroot juice, with each serving providing as much nitrate as three large beets. A few weeks later, the participants drank beetroot juice with the nitrate removed.

Neither the researchers nor the participants knew which juice was being consumed at the time of testing. A day after their last dose, participants returned for testing of their vascular function. The researchers compared how well blood vessels expanded for each woman when they were and were not consuming the nitrate-rich beetroot juice.

The researchers used an ultrasound sensor to monitor how blood flowed through the brachial artery — which is in the upper arm and supplies blood to the hands — during a stress test in which blood flow was restricted in each participant’s forearm for five minutes. When the restriction was removed, researchers measured how blood flow changed in the brachial artery again. 

The results showed that consumption of nitrate-rich beetroot juice each day improved blood flow compared to when the participants drank nitrate-free beetroot juice. The researchers said that this level of improved blood-vessel function — if it could be maintained over the postmenopausal years — could significantly reduce the risk of heart disease. They said that long-term health benefits of beetroot juice have not been studied at this point, but the long-term benefits of nitrate-rich vegetables have been confirmed. 

“Women may need to consume beetroot juice daily — or even more often — to experience all of the potential cardiovascular benefits,” Proctor said. “Still, this research shows that beetroot juice can be very useful in protecting blood vessel health of mid-life women during a period of accelerating heart disease risk.” 

This study included women considered early postmenopausal, or one to six years post-menopause, and late postmenopausal, six or more years post-menopause. Late postmenopausal women saw the same benefits as the early postmenopausal group.  

Delgado Spicuzza said the research team was particularly excited to find that beetroot juice improved blood vessel health for women who had gone through menopause years earlier. Some treatments for protecting cardiovascular health in postmenopausal women — like hormone therapy — are only safe during the first several years post-menopause. After that, hormone therapy can increase the risk of cancers and stroke. 

“Some clinicians are already recommending beetroot juice to men and women with high blood pressure,” Delgado Spicuzza said. “By providing a safe and effective way to improve blood vessel function, beets could help maintain cardiovascular health in postmenopausal women. When you consider that most women are postmenopausal for at least a third of their lives, you can begin to understand the potential significance of these results.”   

Delgado Spicuzza won the Mid-Atlantic American College of Sports Medicine 2023 Doctoral Student Investigator Award for her presentation on this research in fall of 2023. She said it is gratifying to see this research resonate with other researchers and especially with the women in the study, who seemed to embrace the potential of beetroot juice. 

“Several of the participants said that they intended to continue consuming beetroot juice after the study concluded,” she said. “There seems to be a real desire on the part of postmenopausal women to support their cardiovascular health without taking additional medications. In part, I believe beets can be a complimentary food to improve blood vessel health in millions of women as they age.” 

Statins for heart disease prevention could be recommended for far fewer Americans

 

 If national guidelines are revised to incorporate a new risk equation, about 40% fewer people could meet criteria for cholesterol-lowering statins to prevent heart disease, according to a study by researchers at the University of Pittsburgh, Beth Israel Deaconess Medical Center and University of Michigan. Published today in JAMA Internal Medicine, the study examines the potential impact of widespread adoption of the PREVENT equations, which were released by the American Heart Association in November 2023 to update physicians’ go-to calculators for assessing patients’ 10-year risk of heart attack or stroke. 

At a population level, the number of adults recommended for statins could decrease from 45.4 million to 28.3 million. At the same time, the study showed that most people who would be recommended to take statins are not currently taking them.  

“This is an opportunity to refocus our efforts and invest resources in the populations of patients at the highest risk,” said lead author Dr. Timothy Anderson, M.D., M.A.S., a primary care physician at UPMC and health services researcher and assistant professor of medicine at Pitt.  

For their analysis, the team used nationally representative data from 3,785 adults, ages 40 to 75, who participated in the National Health and Nutrition Examination Survey from January 2017 to March 2020. The researchers estimated 10-year risk of atherosclerotic cardiovascular disease (ASCVD) using the Predicting Risk of cardiovascular disease EVENTs (PREVENT) equations and compared the results to risk estimated using the previous tool, known as Pooled Cohort Equations (PCE). The PREVENT equations were developed by the American Heart Association to more accurately represent risk across the current U.S. population, as the PCE equations were based on patient data that were decades old and lacked diversity.  

PREVENT also reflects more recent insights into the biology of ASCVD. Current statin use as well as metabolic and kidney diseases are incorporated into the new calculation, while race has been removed from it, reflecting a growing awareness that race is a social construct. 

Using PREVENT, the team found that among the study’s entire cohort, 10-year risk of developing ASCVD was 4%, half as high as the risk calculated by the PCE (8%). The difference was even larger for Black adults (5.1% versus 10.9%) and for adults between the ages of 70 and 75 (10.2% versus 22.8%).  

An estimated 4.1 million patients who are currently taking statins would no longer be recommended to take them based on PREVENT. For these patients and their physicians, clear and careful communication is key, said Anderson. “We don’t want people to think they were treated incorrectly in the past. They were treated with the best data we had when the PCE was introduced back in 2013. The data have changed.” 

At the same time, it’s important to note that everyone’s risk will inevitably change over time, as well, he added. “For a patient who we now know is at lower risk than we previously thought, if we recommend they stop taking statins, they still could be back to a higher risk five years down the road, for the simple reason that everybody’s risk goes up as we get older.”

Feeling rough after your COVID shot? Congrats, it’s working!

Headache, chills, tiredness may be evidence of a supercharged defense, according to UCSF-led study. 

Fewer than 1 in 4 people in the United States have received last year’s updated COVID-19 vaccine, despite a death toll of more than 23,000 Americans this year. 
 
One of the most common reasons for bypassing the COVID vaccine is concern about side effects like tiredness, muscle and joint pain, chills, headache, fever, nausea and feeling generally unwell. But a new study, led by UC San Francisco, has found that the symptoms indicate a robust immune response that is likely to lessen the chances of infection. 
 
The study, which appears online June 10 in Annals of Internal Medicine, is based on symptom reports and antibody responses from 363 people, who had the Pfizer-BioNTech or Moderna mRNA vaccines when they were first introduced.  
 
After the second dose of the vaccine, the researchers found that those with seven or more symptoms had nearly double the antibody levels of those who did not have symptoms. The participants were mainly in their forties to sixties and had not had the virus. 
 
About 40% of the people in the study also wore a device to monitor their temperature, breathing and heart rate. The researchers found that those whose skin temperature increased by 1 degree Celsius after the second dose had three times the antibody levels six months later, compared to those whose temperature did not increase. 
 
An absence of side effects does not mean the vaccine is not working 
 
“Generally, we found that the higher the number of side effects, the higher the level of antibodies,” said first author Ethan Dutcher, MD, PhD, a postdoctoral researcher in the UCSF Department of Psychiatry and Behavioral Sciences, and the Weill Institute for Neurosciences. “But this wasn’t a hard rule: some people without side effects had better antibodies than some people with side effects.” 
 
As the virus has evolved and fatality rates have fallen, many people are underestimating its impact. “The toll of COVID is still high for some – sickness, lost work, lasting fatigue and the dreaded long COVID,” said co-senior author Elissa Epel, PhD, a vice chair in the UCSF Department of Psychiatry and Behavioral Sciences. “While the symptoms from vaccination can be very unpleasant, it’s important to remember that they don’t come close to the disease’s potential complications,” she said. 
 
“With COVID-19 vaccines likely here to stay, identifying what predicts a strong antibody response will remain important,” said co-senior author Aric Prather, PhD, professor in the UCSF Department of Psychiatry and Behavioral Sciences. 
 
The latest recommendations from the Centers for Disease Control and Prevention are that everyone 6 months and older should receive the updated vaccine, and those 65 and older should receive an additional dose.  

Vigorous exercise may preserve cognition in high-risk patients with hypertension

 People with high blood pressure have a higher risk of cognitive impairment, including dementia, but a new study from researchers at Wake Forest University School of Medicine suggests that engaging in vigorous physical activity more than once a week can lower that risk.

The findings appear online today in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association.

“We know that physical exercise offers many benefits, including lowering blood pressure, improving heart health and potentially delaying cognitive decline,” said Richard Kazibwe, M.D., assistant professor of internal medicine at Wake Forest University School of Medicine and lead author of the study. “However, the amount and the intensity of exercise needed to preserve cognition is unknown.”

In 2015, published findings from the landmark Systolic Blood Pressure Intervention Trial (SPRINT) showed that intensive blood pressure management reduced cardiovascular disease and lowered the risk of death.

SPRINT began in the fall of 2009 and included more than 9,300 participants with hypertension ages 50 and older, recruited from about 100 medical centers and clinical practices throughout the United States. Participants were randomly assigned to a systolic blood pressure goal of either less than 120 mm Hg (intensive treatment) or less than 140 mm Hg (standard treatment). The National Institutes of Health (NIH) stopped the blood pressure intervention earlier than originally planned to quickly disseminate the significant preliminary results, resulting in a new set of guidelines for controlling blood pressure.

In 2019, results of the ancillary SPRINT MIND trial, led by Wake Forest University School of Medicine, showed that intensive control of blood pressure in older people significantly reduced the risk of developing mild cognitive impairment, a precursor of early dementia.

In a secondary analysis of the SPRINT MIND study, Kazibwe and team examined the effect of self-reported sessions of vigorous physical activity (at least once a week) on the risk of mild cognitive impairment and dementia.

People who engaged in one or more sessions of vigorous physical activity per week had lower rates of mild cognitive impairment and dementia.

Kazibwe said that nearly 60% of study participants reported vigorous physical activity at least once a week, even among those aged 75 and up.

“It is welcome news that a higher number of older adults are engaging in physical exercise. This also suggests that older adults who recognize the importance of exercise may be more inclined to exercise at higher intensity,” Kazibwe said.

However, the research team found the protective impact of vigorous exercise was more pronounced for those under 75.

“While this study provides evidence that vigorous exercise may preserve cognitive function in high-risk patients with hypertension, more research is needed to include device-based physical activity measurements and more diverse participant populations,” Kazibwe said.

Poor quality diet might lead to depression and anxiety

 Eating a poor quality diet might lead to brain changes that are associated with depression and anxiety. This is according to a first-of-its-kind study into the brain chemistry and structure, and diet quality of 30 volunteers.

Brain scans show changes in neurotransmitters and grey matter volume in people who have a poor diet, versus those who adhere to a Mediterranean style diet, which is considered very healthy. The researchers also found that these changes are associated with rumination, a part of the diagnostic criteria for conditions affecting mental health, such as depression and anxiety.

This research was carried out by the University of Reading, Roehampton University, FrieslandCampina (Netherlands), and Kings College London, and is published in Nutritional Neuroscience.

When someone eats a poor quality diet, there is reduced gamma aminobutyric acid (GABA) and elevated glutamate – both neurotransmitters, along with reduced grey matter volume – in the frontal area of their brain. This could explain the association between what we eat, and how we feel.

Dr Piril Hepsomali, University of Reading, said: “We can eat ourselves well! Ultimately, we see that people who have an unhealthy diet – high in sugar and saturated fat – have imbalanced excitatory and inhibitory neurotransmission, as well as reduced volume of grey matter in the frontal part of the brain. This part of the brain is involved in mental health issues such as depression and anxiety.”

The exact reason that diet affects the brain in this way is still under investigation. It’s possible that obesity and dietary patterns that are high in saturated fats cause changes in glutamate and GABA metabolism and neurotransmission, as has been shown in animal studies.

Distinct alterations of the gut microbiome, due to dietary patterns that are high in saturated fats, is thought to have an impact on cell machinery that drives both GABA and glutamate production.

A high saturated fat, high sugar, diet has also been shown to reduce the number of parvalbumin interneurons, which perform the role of delivering GABA to where it is needed.

Unhealthy diets also have an impact on glucose, making blood glucose and insulin higher. This increases glutamate in the brain and plasma, thus reducing GABA production and release. Having a diet high in fat and cholesterol can cause changes in cell membranes that alter the release of neurotransmitters, too.

These changes in brain chemistry might lead to changes in the brain grey matter volume, as observed in this study.

Dr Hepsomali continued: “I would like to note that GABA and glutamate are intimately involved in appetite and food intake, too. Reduced GABA and/or increased glutamate might also be a driving factor in making unhealthy food choices. So, there may be a circular relationship between eating well, having a healthier brain and better mental wellbeing, and making better food choices to eat well.”