Welcome to the September 2022 issue of Research Extracts. “The Extracts” is designed to keep busy practitioners and savvy consumers up to date on the latest research on diet, nutrients, botanicals, the microbiome, the environment, and lifestyle approaches to good health. Our medical team, which includes NDs, MDs, PhDs, RDs, an MS, and an LAc, has summarized the essence of several interesting recent studies.

In this issue: (1) this month’s Mental Health Moment – stress and immunity, (2) prenatal supplement recommendations update, (3) antibiotics and the microbiome, and (4) Jarlsberg cheese and osteoporosis.

Mental Health Moment: How Stress Affects Immunity

With a new school year underway, stress levels might be rising for parents, students, and teachers. In addition, being back in the classroom opens the door to more sharing of germs and exposure to different pathogens. The connection between stress and immune system function was examined in a recent study that explores the role of stress in brain circuits and immune responses. 

Acute stress can affect the body’s ability to respond to immune challenges. Key stress hormones, like norepinephrine and cortisol, contribute to the dispersal of immune cells (monocytes, lymphocytes, and neutrophils) throughout the body. This study shows there are distinct signaling pathways that control immune cell mobilization after an acute stress event. In one pathway, stress up-regulates the corticotropin-releasing hormone (CRH) neurons in the hypothalamus. These CRH neurons are responsible for the movement of immune cells (monocytes and lymphocytes) from peripheral organs to the bone marrow to be available for immune support. Another pathway affects a different set of immune cells – the neutrophils. Neutrophil mobilization increases during defensive behaviors like fight or flight when skeletal muscle and the descending motor pathways are in action.

In studying autoimmunity in mice, those with autoimmune encephalomyelitis (EAE) who were under stress had lower clinical severity scores compared to unstressed mice. Acute stress increased signaling of the CRH neurons to activate the immune cells. The mice who lack CRH (unstressed) were more susceptible to EAE and potentially similar autoimmune diseases.

To compare the immune system’s response to viral infection, stressed mice were exposed to SARS-CoV-2 and influenza A as sample viruses. Stressed mice had higher viral titers compared to unstressed mice. These findings indicate that acute stress during the early phase of a viral exposure might impair the host’s adaptive immunity against an infection.

So, while acute stress appeared to interfere with the immune response to a virus, it seemed to be protective for development of an autoimmune condition. Understanding the role of stress in these two immune responses, autoimmune and viral, can help us prioritize stress management, particularly in times of illness or increased exposure to pathogens.

Contributed by Carly Duffy, MPH, RD

Reference

How well do you respond to stress? Test your levels of adrenal hormones cortisol and DHEA with Thorne’s easy, at-home Stress Test. Diet, lifestyle, and supplement recommendations based on your results are included.

Optimal Prenatal Supplementation: What Does the Evidence Say?

Experts agree that a prenatal supplement is a good idea for most women who are pregnant or trying to conceive. However, prenatal supplements vary widely in the nutrients they contain. A recent article in Maternal Health, Neonatology, and Perinatology provides evidence-based recommendations for prenatal supplementation. The authors reviewed research literature, provided recommendations for optimal supplementation, and compared nutrient recommendations to the levels of nutrients found in 180 commercial prenatal supplements.

Blood levels of many nutrients decrease during pregnancy due to increased demand. In addition, dietary intakes of many nutrients often fall below recommended intakes, particularly in a typical U.S. diet. The authors recommend the following nutrients be included in a prenatal supplement to support the health of mother and baby:

  1. Vitamin A – supports skin, bones, and eyesight*
  2. Vitamin C – supports gums, teeth, and bones; benefits “morning sickness”*
  3. Vitamin D – supports bones, teeth, skin, and eyesight*
  4. Vitamin E – supports heart and lungs*
  5. Vitamin K – supports blood and bones; benefits “morning sickness”*
  6. Vitamin B1 – supports heart and nervous system*
  7. Vitamin B2 – supports white and red blood cells, normal thyroid function, and eyes*
  8. Vitamin B3 – supports cellular energy production, skin, nervous system, and digestive tract*
  9. Vitamin B5 – supports cellular energy production and normal adrenal function*
  10. Vitamin B6 – supports red blood cell formation, production of hormones and neurotransmitters, and benefits morning sickness*
  11. Biotin (vitamin B7) – supports metabolism and development of soft tissues*
  12. Folate (vitamin B9) – supports brain and spinal cord, nervous system, and red blood cell formation*
  13. Vitamin B12 – supports nervous system and red blood cell formation*
  14. Choline – supports brain and nervous system, cognitive function, and cellular health*
  15. DHA – supports brain, nerves, cognitive function, and eyes*
  16. Inositol – supports blood sugar and a normal insulin response*

Contributed by Jennifer L. Greer, ND, Med

For complete details of the authors’ findings and recommendations, click on the reference link below.

Reference

Explore Thorne’s Prenatal DHA, Basic Prenatal with choline, and Ovarian Care with inositol, folate, and CoQ10.

Acute and Persistent Effects of Commonly Used Antibiotics on Gut Microbiome in Humans

A prospective, longitudinal study examined the impact on the gut microbiome of four antibiotic treatments (azithromycin (AZM), levofloxacin (LVX), cefpodoxime (CPD), and CPD+AZM), commonly misprescribed for viral pneumonia, in 20 healthy volunteers (n=5 per group).

Researchers looked at multiple gut microbiome samples from each participant prior to antibiotic use, during the course of the antibiotic, and up to six months after antibiotic use for a total of 15 samples for each participant. These samples were then compared to the microbiomes of hospitalized, critically ill patients.

Generally, there was a remarkable similarity in the effect of each treatment on species richness and viable colony forming unit (CFU) concentrations with antibiotic-specific enrichment in taxonomy and resistance. AZM (and CPD+AZM) had the slowest microbiome recovery, the most specific differences, and the most change from pre-treatment. Microbiomes with the lowest diversity pre-treatment had the largest change after antibiotics and had microbial similarities to the critically ill ICU patients. By six months after treatment, most volunteers returned to a similar level of taxonomic diversity but saw long-term increases in antibiotic-resistant genes, changes to the functional output of the microbiome, and an altered taxonomic state.

The study concludes that short courses of antibiotic use, although critical and lifesaving, can cause both short-term and long-term changes to the microbiome, including extended antibiotic resistance, even in previously healthy microbiomes. Studies such as this also help to identify which antibiotics might have the greatest long-term impact on the gut microbiome.

Contributed by Laura Kunces, PhD, RD

Link below for more details.

Reference

If you are interested in your gut microbiome status, have recently finished a course of antibiotics, or are anticipating antibiotic use, Thorne’s Gut Health Test evaluates your gut microbiome diversity and all of the specific species mentioned in this publication.

Jarlsberg Cheese Could Help Prevent Osteoporosis

Certain types of cheeses are good sources of vitamin K2, while others are not because it depends on which bacteria are used in the fermentation process. Jarlsberg cheese is rich in vitamin MK-9 and MK-9(H4) – two longer-chain K2 isomers – while Camembert is not.

In a trial of healthy Norwegian women (average age 33), 41 were asked to eat 57 grams of Jarlsberg cheese daily for six weeks, while 25 were assigned to eat 50 grams of Camembert cheese daily for six weeks. At the end of six weeks, the women eating the Camembert were switched to eating the Jarlsberg for another six weeks – a semi-crossover trial. Markers of bone formation including osteocalcin (total, carboxylated, and undercarboxylated – the latter a sign of low vitamin K), procollagen type-1 N-terminal propeptide (PINP), C-telopeptide type-1 collagen, and vitamin K2 were evaluated at the beginning of the study and following the next two 6-week periods.

After six weeks, PINP, total osteocalcin, carboxylated osteocalcin, and the ratio of carboxylated-to-undercarboxylated osteocalcin increased in the Jarlsberg group. The Camembert group experienced no change in PINP and slight decreases in the other variables. When the women in the Camembert group switched to Jarlsberg, they experienced the same improvements as the women in the original Jarlsberg cheese group.

These results indicate increased bone formation can be attributable to the consumption of Jarlsberg cheese, which implies benefit for bone support, in contrast to eating Camembert cheese, which did not appear to offer bone support, presumably because of its low vitamin K2 content.

Contributed by Kathi Head, ND

Reference

Thorne’s Vitamin K combines K1 with two forms of K2 (MK-4 and MK-7).