Welcome to the November 2024 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 and wellness. Our medical team, including NDs, MDs, PhDs, RDs, an MS in clinical nutrition, an MS in biology, and an LAc, summarizes the essence of several interesting recent studies.

In this issue: (1) Mental Health Moment: camembert cheese and cognitive function, (2) creatine and cognitive support after sleep deprivation, (3) dietary zinc and endometriosis, and (4) omega-3 status around the world.

Mental Health Moment: Camembert Cheese Protects Cognitive Function

Dairy-food consumption has been widely studied for its health effects, specifically its impact on the brain. However, different types of dairy products may exert different effects due to variables such as fat content or fermentation. This observational cohort study explored the impact of cheese consumption, including cheese type, and cognitive function in Japanese women (n=1,035) ages 65 and older.

The participants completed anthropometric assessments, physical function tests, and cognitive tests including the mini-mental state examination (MMSE) to assess the risk of cognitive decline. Mild cognitive decline was defined as scores between 20 and 26. Participants with scores of 19 or lower were excluded as this may indicate mild-to-moderate dementia. Frequency and type of cheese intake were assessed via a food frequency questionnaire.

In contrast to the cheese intake group, the non-cheese intake group had poorer physical function results, lower dietary variety scores, higher geriatric depression scores, and lower MMSE scores, indicating increased cognitive decline.

The cheese intake group was divided into cheese types, of which Camembert cheese was consumed by 12.2% of the group at least once or twice a week, and up to every day. Other cheese types included processed cheese, fresh cheese, and blue mold cheese. The Camembert intake group had higher MMSE scores compared to other cheese intake groups, indicating that consuming Camembert cheese may prevent mild cognitive decline. Camembert cheese is fermented, which offers additional benefits beyond the dairy nutrition. Through the gut-brain axis, it is presumed that probiotics and their metabolites, present in the fermented cheese, can support cognitive function as well as promoting a healthy microbial balance in the gut microbiome.

Note: To further support a diverse gut microbiome, Thorne offers several probiotics. Whether you’re looking for a single strain probiotic for everyday GI support or something more specialized to also target weight management, Thorne has you covered. Check out our collection of probiotics here.

Contributed by Carly Duffy, MPH, RD

Reference

Single-Dose Creatine Supports Cognitive Function After Sleep Deprivation

Sleep deprivation, whether from cramming study sessions, shift work, or newborn care, can increase the risk of accidents, reduce performance, and lead to chronic disease. Creatine monohydrate research has shown promise in supporting neurodegenerative condition pathways, so researchers sought to understand how creatine might affect brain metabolites and cognitive impairments associated with sleep deprivation. 

In this randomized, placebo-controlled, double-blind, cross-over study of 15 healthy women (average age 23) with no history of a sleep disorder, researchers examined the response of several brain metabolites and cognitive performance overnight in individuals who have a normal sleep schedule from 11 p.m. to 7 a.m. Participants did baseline testing at 8:30 p.m., then consumed 0.35 grams per kilogram body weight of creatine (approximately 25 grams for a 160-pound person) or placebo on the night of no sleep; the same scans and cognitive tests were performed at midnight, 2 a.m., and 4 a.m. The test was then repeated with the opposite treatment, with no fewer than five days between active or placebo testing.

The results of the brain scans showed that creatine was bioavailable to the brain and subjects reported feeling less fatigue compared to placebo while sleep deprived. Creatine alleviated numerous metabolic changes of cellular stress evoked by sleep deprivation, including changes in phosphates, pH levels, improved phosphocreatine levels, declines in ATP levels, and improved cognitive performance and processing speed compared to placebo. 

This study is unique in showing that single doses of creatine can have effects in as little as four hours and lasting nine hours for supporting fatigue-related cognitive declines.

Note: Thorne’s Creatine contains 5 grams of pure creatine monohydrate per serving; it’s NSF Certified for Sport®. The one-time dose used in this study is considerably higher than the recommended dose for Thorne’s Creatine.

Contributed by Laura Kunces, PhD, RD

Reference

Dietary Zinc Intake and Endometriosis

Endometriosis affects more than 176 million women worldwide, and an appropriate diagnosis can take up to 12 years after onset of symptoms. With a significant impact on both quality of life and health-care costs, a better understanding of risk factors associated with the disease could lead to prevention of symptoms and onset for many women. Zinc is an important dietary nutrient that plays a role in modulating the body’s immune response and helping to protect against oxidative stress, two factors that may play a role in the development of endometriosis. The most common dietary sources of zinc are red meat, poultry, oysters, beans, and nuts.

A cross-sectional study of American women explored the relationship between dietary zinc intake and endometriosis risk. Data from the National Health and Nutrition Examination Survey (NHANES) collected between 1999 and 2006 were used in this study and included information from 4,315 women ages 20-54. Women with endometriosis were defined by those who responded “yes” to the question, “Has a doctor or other health professional ever told you that you had endometriosis?” Dietary zinc intake was determined based on responses to two 24-hour dietary recall interviews conducted 3-10 days apart.

The primary outcome of the study revealed that higher dietary zinc intake was associated with lower risk of endometriosis among American women. However, at mid-level zinc intake, the association with endometriosis was not significant. The authors noted a need for further research to better elucidate the threshold at which zinc intake might benefit endometriosis risk. In addition, the study also found significant associations between other lifestyle factors and endometriosis, including age, race, family income, education level, smoking status, and use of dietary supplements. This further illustrates the complex nature of endometriosis and the many factors that might play a role in its development.

Note: While the best sources of dietary zinc are whole foods, a zinc supplement can help to bridge nutrient gaps as part of a healthy diet. Thorne’s Zinc Bisglycinate and Zinc Picolinate are well-absorbed forms of zinc, available in 15 mg and 30 mg capsules.

Contributed by Jennifer L. Greer, ND, MEd

Reference

Omega-3 Intakes and Shifts Worldwide

This study examined the average omega-3 fatty acid (EPA and DHA) levels in countries around the world; it’s an update of a 2016 study – the first ever of its kind. Researchers from Canada, Germany, Spain, and the United States identified 328 studies including 342,864 subjects ages 16 and older. Omega-3 status was assessed by Omega-3 Index (O3I), which measures the percentage of EPA and DHA in the fatty acid content of red blood cell membranes. In studies that were included where the O3I was not provided, the blood levels of EPA and DHA had to be reported in metrics that could be converted to O3I. The levels were divided into quartiles: favorable (>8), moderate (>6-8), low (>4-6), and very low (≤4).

With 48 countries or regions represented, the researchers reported finding most countries in the low to very low ranges. It should be noted that 49% of the studies were from North America (mostly the United States), while 43% were from Europe. Thus, 92% of the studies represented only 15% of the world’s countries, with the southern hemisphere particularly underrepresented. Some notable results, including some changes between the 2016 and present studies:

  •  Japan, S. Korea, Greenland, Norway, and Alaska (Inuit) had desirable levels in both studies.
  • United States, Canada, Italy, Turkey, United Kingdom, Ireland, and Greece moved from very low to low between 2016 and 2024.
  • France, Spain, and New Zealand moved from low to moderate.
  • Finland and Iceland moved from moderate to desirable.
  • Iran, Egypt, India, and Brazil fared particularly poorly.

Clearly the countries with the highest fish intake diets faired the best. However, the improvement over the past eight years in several of the countries indicates the growing awareness of the health benefits of omega-3 fatty acids and an increase in dietary supplementation.

Note: Knowing the importance of EPA and DHA to good overall health, Thorne offers a variety of omega-3s to support the health needs of the whole family – for children, pregnancy, cardiovascular/lipid support, cognitive function, and general foundational support.

Contributed by Kathi Head, ND

Reference