Research Briefs for Practitioners – July 2023 - Dr. Michael Ruscio, DC

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Future of Functional Health Review Clinical Newsletter

Research Briefs for Practitioners – July 2023

by the Ruscio Institute for Functional Health Clinical Team

Medically reviewed & fact checked by a
board-certified doctor
Medically reviewed & fact checked by a
board-certified doctor
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Episodes 105 & 106

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Effect of probiotic yogurt consumption on glycemic control and lipid profile in patients with type 2 diabetes mellitus: A randomized controlled trial

  • Does probiotic yogurt improve metabolic health?
  • RCT: 72 patients with type 2 diabetes were randomized to:
    • Yogurt + placebo
    • Yogurt + probiotics
      • Lactobacillus acidophilus and Bifidobacterium lactis, ~1 billion CFU/day 
  • After 3 months, compared to placebo, probiotic yogurt led to improved:
    • HbA1c (-0.8% vs -0.2%) 
    • LDL-C (-8.6 mg/dl vs. 0 mg/dl) 


The Effects of Probiotics/Synbiotics on Glucose and Lipid Metabolism in Women with Gestational Diabetes Mellitus: A Meta-Analysis of Randomized Controlled Trials

  • Do probiotics improve gestational diabetes?
  • Meta-analysis: 11 RCTs, 779 patients with gestational diabetes randomized to:
    • Control
    • Probiotics +/- prebiotics
      • Lactobacillus, Bifidobacterium, Streptococcus thermophilus
      • Inulin, fructooligosaccharides
  • Compared to control, probiotics +/- prebiotics led to improved:
    • Fasting glucose
    • Fasting insulin
    • Total cholesterol


A systematic review and meta-analysis of randomized controlled trials investigating the effects of probiotics on oxidative stress in healthy adults

  • Do probiotics reduce oxidative stress?
  • Meta-analysis: 9 RCTs involving healthy participants randomized to:
    • Placebo
    • Probiotics
  • Compared to placebo, probiotics led to:
  • Increased antioxidant capacity (large effect size)
  • Increased glutathione levels (small effect size)
  • Reduced oxidative stress (moderate effect size)


Lactiplantibacillus Plantarum CCFM8724 Reduces the Amounts of Oral Pathogens and Alters the Oral Microbiota in Children With Dental Caries: a Randomized, Double-Blind, Placebo-Controlled Trial

  • Do probiotics improve oral dysbiosis in children?
  • RCT: Children with dental caries, randomized to:
    • Placebo
    • Probiotics
      • Lactobacillus plantarum
  • After 1 month, probiotics led to reductions in bacteria associated with cavities, including:
    • Streptococcus mutans 
    • Candida albicans


Effectiveness of vaginal estriol with lactobacilli on urinary symptoms in postmenopausal women: a randomized-controlled trial

  • Do probiotics improve urinary symptoms in women?
  • RCT: 76 post-menopausal women with lower urinary tract symptoms randomized to:
    • Placebo
    • Estriol + Lactobacillus
      • Tablet, administered vaginally
  • After 1 month, estriol + probiotics did NOT improve:
    • Lower urinary tract symptoms


Effects of Probiotics on Autism Spectrum Disorder in Children: A Systematic Review and Meta-Analysis of Clinical Trials

  • Do probiotics improve autism symptoms?
  • Meta-analysis: 7 RCTs, N = 268 autistic children randomized to:
    • Control
    • Probiotics
      • Varied by study, included lactobacillus, bifidobacterium, Enterococcus faecalis
  • Results
    • Multi-strain probiotics improved behavioral symptoms (small effect) 
    • Single-strain probiotics had NO effect


Effect of Probiotic Supplementation on Gut Microbiota in Patients with Major Depressive Disorders: A Systematic Review

  • Do probiotics improve the microbiota in depressed patients?
  • Meta-analysis: 5 RCTs, patients with major depression, randomized to:
    • Placebo
    • Probiotics
      • Lactobacillus and bifidobacterium, up to 900 billion CFU/day
  • After 1-2 months, probiotics did NOT improve:
    • Depressive symptoms
    • Gut microbiota composition
  • Note: Diet was not controlled for in most of the studies


Early Probiotic Supplementation of Healthy Term Infants with Bifidobacterium longum subsp. infantis M-63 Is Safe and Leads to the Development of Bifidobacterium-Predominant Gut Microbiota: A Double-Blind, Placebo-Controlled Trial

  • Do probiotics improve gut health in newborns?
  • RCT: 110 healthy newborns were randomized to:
    • Placebo
    • Probiotics
      • Bifidobacterium longum infantis, 1 billion CFU/day
  • After 3 months, compared to placebo, the probiotic group had improvements in:
    • Stool frequency
    • Stool form
    • Spit up frequency
  • NO adverse events occurred
  • Note: Probiotic was added to feeding bottle or medicine dropper 


Randomised controlled trial of melatonin for pediatric functional abdominal pain disorders

  • Does melatonin enhance the efficacy of probiotics for abdominal pain?
  • RCT: 42 children with abdominal pain, randomized to the following for 1 month:
    • Placebo + Probiotics
      • Lactobacillus rhamnosus GG
    • Melatonin + Probiotics
      • 3 or 5 mg Melatonin
  • After 3 months, compared to probiotics alone, melatonin + probiotics led to:
    • Greater reduction in abdominal pain


Safety and efficacy of probiotic supplements as adjunctive therapies in patients with COVID-19: A systematic review and meta-analysis

  • Are probiotics effective for COVID-19?
  • Meta-analysis: 8 RCTs, 1,027 acute COVID-19 patients, randomized to:
    • Control (placebo or standard of care) 
    • Probiotics
      • Lactobacillus, Bifidobacterium, Streptococcus thermophilus, Pediococcus, Bacillus
  • Compared to control, probiotics reduced the risk of:
    • Respiratory symptoms by 63%
    • Diarrhea by 39%
    • Adverse events of COVID-19 treatments by 38%
  • Probiotics did NOT reduce mortality risk


Synbiotic supplement for treatment of iron deficiency anaemia in haemodialysis patients: A randomized controlled trial

  • Do synbiotics improve iron deficiency anemia? 
  • RCT: 46 patients with iron deficiency anemia, randomized to: 
    • Placebo
    • Synbiotics 
  • After 2 months, compared to placebo, synbiotics led to improved: 
    • Ferritin
    • Anemia (RBC, hemoglobin, hematocrit)

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Prebiotic Galacto-Oligosaccharides and Fructo-Oligosaccharides, but Not Acacia Gum, Increase Iron Absorption from a Single High-Dose Ferrous Fumarate Supplement in Iron-Depleted Women

  • Do PRE-biotics improve iron absorption?
  • RCT: 30 women with iron deficiency, all treated with iron and randomized to:
    • Placebo 
    • Galacto-oligosaccharides (GOS) 
    • Fructo-oligosaccharides (FOS)
    • Acacia gum
  • After 2 weeks, compared to control, the results showed that:
    • GOS and FOS increased iron absorption by ~50%
    • Acacia gum had NO affect iron absorption


Prevalence of Small Intestinal Bacterial Overgrowth Syndrome in Patients with Non-Alcoholic Fatty Liver Disease/Non-Alcoholic Steatohepatitis: A Cross-Sectional Study

  • Is SIBO common in fatty liver patients?
  • Observational study: 95 patients with fatty liver disease and 30 healthy controls
    •  All tested for SIBO
  • Compared to healthy controls, patients with fatty liver had:
    • Higher SIBO prevalence (23% vs 3%)


Small Intestinal Bacterial Overgrowth Complicating Gastrointestinal Manifestations of Systemic Sclerosis: A Systematic Review and Meta-analysis

  • How common is SIBO in systemic sclerosis patients?
  • Meta-analysis: 28 observational studies involving:
    • Control patients
      • Healthy
      • Unexplained GI symptoms
    • Systemic sclerosis patients
      • Chronic connective tissue disorder, commonly associated with GI dysmotility
  • Compared to controls, systemic sclerosis patients had:
    • 7-fold greater risk of SIBO (37% vs 5%)
  •  Use of PPIs in systemic sclerosis patients was associated with:
    • Higher SIBO prevalence (43% vs 29%)


Helicobacter pylori Infection is Associated with Decreased Odds for Eosinophilic Esophagitis in Mexican Patients

  • How does H. pylori infection impact allergic conditions?
  • Observational study: 38 patients with eosinophilic esophagitis, 152 controls 
  • H. pylori infections was associated with: 
    • 33% lower rates of eosinophilic esophagitis
    • 38% lower rates of allergic conditions in general
    • Allergic rhinitis, food allergies


Meta-analysis: Use of proton pump inhibitors and risk of gastric cancer in patients requiring gastric acid suppression

  • Does acid-suppressing medication increase the risk of stomach cancer? 
  • Observational study: ~6 million participants using either
    • Anti-histamine acid blockers (control group) 
    • Proton pump inhibitor (PPI)
  • Compared to those taking anti-histamine blockers, the use of PPI medications:
    • Did NOT increase the risk of stomach cancer


Efficacy and safety analysis of prucalopride in refractory chronic constipation cases in a tertiary care hospital in Eastern India: A randomized, single-blind, placebo-controlled study

  • Is a prokinetic medication effective for chronic constipation? 
  • RCT: 180 patients with treatment-resistant constipation, randomized to: 
    • Placebo
    • Prucalopride
  • After 3 months, compared to placebo, prucalopride led to more patients experiencing:
    • +3 bowel movements/week (41% drug vs 12% placebo
  • “Prucalopride is effective in laxative refractory CC cases with a good safety profile.”


Factors Affecting Delayed Gastric Emptying and Long-Term Outcomes of Children With Gastric Emptying

  • What factors are predictive of slow gastric motility? 
  • Observational study: 285 kids with suspected delayed gastric emptying
    • Common symptoms include vomiting, reflux and abdominal pain
  • Delayed gastric emptying was present in 61% of kids, and highly associated with: 
    • Prior abdominal surgery 


Alterations to the duodenal microbiota are linked to gastric emptying and symptoms in functional dyspepsia

  • Are diet and microbiome composition associated with functional dyspepsia?
    • Observational study: 56 patients with functional dyspepsia, 30 controls, all participants underwent
      • Dietary assessment
      • Duodenal biopsy to analyze microbiota
  • Compared to healthy controls, functional dyspepsia was associated with: 
    • Higher levels of Firmicutes, Bacteroidota and Fusobacteriota
    • NO difference in diet quality
  • Commentary: This study illustrates not all gastrointestinal symptoms are due to dietary choices.


The relationship of major depressive disorder with Crohn’s disease activity

  • How common is depression in patients with Crohn’s disease?
  • Observational study: 283 patients with Crohn’s disease 
  • In Crohn’s patients, major depression was:
    • Present in 41.7% of patients
    • More common in active Crohn’s disease


Effect of gut microbiota modulation on sleep: a systematic review and meta-analysis of clinical trials

  • Do gut-targeted therapies improve sleep? 
  • Meta-analysis: 18 RCTs, participants randomized to: 
    • Control
    • Prebiotic 
    • Probiotics
  • Compared to control, neither prebiotics or probiotics improved: 
    • Sleep quality 
    • Sleep duration


Characterization of dysbiosis of the conjunctival microbiome and nasal microbiome associated with allergic rhinoconjunctivitis and allergic rhinitis

  • Is nasal dysbiosis associated with allergy symptoms? 
  • Observational study: 60 patients with allergies, 34 healthy controls
    • Nasal and conjunctival microbiome analyzed
  • Compared to healthy controls, patients with allergies had reduced diversity of: 
    • Nasal microbiome 
    • Conjunctival microbiome

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Thyroid & Hormones

Is There a Relation between Hypothyroidism and Polycystic Ovary Syndrome and its Metabolic Components?

  • Is thyroid disease more common in PCOS patients?
  • Observational study: 41 PCOS patients, 41 healthy controls 
  • Compared to healthy controls, women with PCOS had higher:
    • Subclinical hypothyroidism incidence
    • TPO antibodies


Effects of carnitine on glucose and lipid metabolic profiles and fertility outcomes in women with polycystic ovary syndrome: A systematic review and meta-analysis

  • Does carnitine improve fertility in women with PCOS?
  • Meta-analysis: 7 RCTs, 839 women with PCOS and infertility randomized to:
    • Placebo + standard treatment
    • Carnitine + standard treatment
  • Compared to placebo, carnitine supplementation led to:
    • Higher pregnancy rates (11x increased chance
  • NO change in miscarriage rates


Impact of lead exposure on the thyroid glands of individuals living in high- or low-lead exposure areas

  • Does lead exposure affect thyroid function? 
  • Observational study: 187 hypothyroid patients, 197 euthyroid patients
    • Blood lead measured on all patients
  • High blood lead was NOT associated with 
    • Worse thyroid function (TSH, fT4)
    • Thyroid antibodies
  • High blood lead was associated with:
    • Larger thyroid gland
    • More thyroid nodules


Maternal hypothyroidism and adverse outcomes of pregnancy

  • Does thyroid dysfunction affect pregnancy outcomes?
  • Observational study: 14,744 women, categorized by thyroid function
  • Rates of spontaneous abortions were:
    • 12.5% if TSH ≥10 mIU/L
    • 10% if overt hypothyroid
    • 6.5% if TSH <10 mIU/L
  • Thyroid antibodies did NOT affect pregnancy outcomes


Achievements in Hypothyroidism Treatment with Herbal Medicine: A Systematic Review of Randomized Controlled Trials

  • Can herbal medicines improve hypothyroidism?
  • Systematic review: 4 RCTs, 186 hypothyroid patients treated with various herbal medicines
  • Compared to controls, the herbal medicines shown to improve hypothyroidism most were:
    • Nigella sativa
      • Improved TSH, T3, and BMI
    • Ashwagandha
      • Improved TSH, T3, and T4
    • Peppermint
      • Improved fatigue


Association of thyroid disease with risks of dementia and cognitive impairment: A meta-analysis and systematic review

  • Are thyroid conditions associated with increased risk of dementia?
  • Meta-analysis: 15 studies
  • Dementia risk was NOT associated with:
    • Subclinical hypothyroidism
    • Hypothyroidism
  • Dementia risk was associated with: 
    • Subclinical hyperthyroidism (1.5x increased risk)
      • Suppressed TSH
    • Hyperthyroidism (1.1x)


The effect of abdominal massage and stretching exercise on pain and dysmenorrhea symptoms in female university students: A single-blind randomized-controlled clinical trial

  • Can simple lifestyle interventions improve painful periods? 
  • RCT: 63 women with menstrual symptoms were randomized to:
    • Control
    • Abdominal massage
    • Stretching
  • Abdominal massage was most effective for menstrual-related:
    • Abdominal and back pain
    • Fatigue
  • Stretching was most effective for: 
    • Improving mood


The effect of yoga on pain level in primary dysmenorrhea

  • Can yoga improve menstrual irregularities?
  • RCT: 60 women with primary dysmenorrhea, randomized to:
    • Control
    • Yoga
      • 1 session/week x 3 months
  • After 3 months, compared to control, the yoga group had significant improvement in:
    • Menstrual pain


The effect of vitamin D on the severity of dysmenorrhea and menstrual blood loss: a randomized clinical trial

  • Does vitamin D improve menstrual irregularities?
  • RCT: 84 college-aged women with dysmenorrhea and vitamin D deficiency were randomized to:
    • Placebo
    • Vitamin D
      • 100,000 IU/day for 3 days
  • Over the next 2 menstrual cycles, vitamin D treatment led to:
    • Improved menstrual pain
    • NO reduction in heavy bleeding

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Diet & Lifestyle

Slow breathing for reducing stress: The effect of extending exhale

  • Does slow breathing improve stress response? 
  • RCT: 100 participants randomized to 2 slow breathing practices
    • Exhale longer than inhale
    • Exhale equal to inhale
  • After 3 months, either slow breathing practices led to:
    • Reduced anxiety
    • NO difference in heart rate variability


The Effect of Meditation-Based Mind-Body Interventions on Symptoms and Executive Function in People With ADHD: A Meta-Analysis of Randomized Controlled Trials

  • Does mindfulness improve ADHD?
  • Meta-analysis: Participants with ADHD randomized to: 
    • Control
    • Mindfulness-based interventions
      • Tai Chi, Yoga, Qigong, mindfulness
  • Mindfulness-based practices lead to improvements in: 
    • Attention (small effect) 
    • Hyperactivity (small effect) 
    • Executive function (small effect) 
      • A set of mental skills that include working memory, flexible thinking, and self-control


Randomised clinical trial: Psychological intervention improves work productivity and daily activity by reducing abdominal pain and fatigue in Crohn’s disease

  • Does mindfulness and cognitive behavioral therapy improve IBD?
  • RCT: 142 patients with Crohn’s disease were randomized to:
    • Usual treatment
    • Mindfulness + CBT
  • After 3 months, compared to usual treatment, mindfulness + CBT improved:
    • Abdominal pain
    • Fatigue
    • Work productivity


Meditation practices and their relationship with eating behavior, weight changes, and mental health in adults from different regions of Brazil: A cross-sectional study

  • Does meditation lead to healthier eating habits?
  • Observational study: 764 participants were surveyed regarding their meditation habits:
  • Compared to non-meditators, people who meditated had:
    • Healthier eating habits
    • Greater weight loss 
      • Only in overweight individuals
  • Those who meditated for >13 months had:
    • Lower anxiety


Effects of co-ingesting glucose and whey protein on blood glucose, plasma insulin and glucagon concentrations, and gastric emptying, in older men with and without type 2 diabetes

  • Does whey protein help control post-meal blood sugar levels?
  • RCT: 20 older men with and without type 2 diabetes, randomized to drink:
    • Control (water) 
    • Glucose
    • Whey protein
      • 30 grams
    • Glucose + whey protein
  • The addition of whey protein to a glucose drink led to:
    • Lower blood sugar spikes (-29 mg/dl) 


Acute Effects of Coffee Consumption on Health among Ambulatory Adults

  • What impact does coffee consumption have on overall health? 
  • RCT: 100 healthy adults were assigned on random days to:
    • Coffee consumption
    • Coffee avoidance
  • After 2 weeks, coffee consumption was associated with:
    • ~1000 more steps per day
    • 35 fewer minutes of sleep
    • No difference in blood sugar


The Effect of Non-Nutritive Sweetened Beverages on Postprandial Glycemic and Endocrine Responses: A Systematic Review and Network Meta-Analysis

  • Do artificial sweeteners negatively affect blood sugar control? 
  • Meta-analysis: 36 studies, 472 participants (healthy, diabetics), randomized to: 
    • Control
      • Water or sugar
    • Artificial sweeteners
      • Equal, Splenda, Stevia, Sweet ‘N Low, Nutrasweet
  • Compared to controls, artificial sweeteners had NO acute effect on: 
    • Blood sugar
    • Insulin
    • Ghrelin (hunger hormone) 
    • Leptin
    • Endocrine hormones (Peptide YY, glucagon, GLP-1, GIP) 
  • ‘The available evidence suggests that non-nutritive sweetened beverages have no acute metabolic and endocrine effects, similar to water.’


Comparison of seven popular structured dietary programmes and risk of mortality and major cardiovascular events in patients at increased cardiovascular risk: systematic review and network meta-analysis

  • Are certain dietary interventions better for improving longevity?
  • Meta-analysis: 40 studies, 35,548 participants following various diets
    • Mediterranean
    • Low fat 
      • 20-30% fat intake
    • Very low fat 
      • 10-20% fat intake
    • Low fat + low sodium 
    • Modified fat
      • Replaced saturated fat with polyunsaturated fat 
    • Plant-based (Ornish, Pritikin) 
  • The mediterranean diet was most effective for reducing risk of:
    • Heart attacks by 52%
    • Cardiovascular death by 45%
    • Stroke by 35%
    • All-cause mortality by 28%
  • NO other diet, aside from the low-fat diet, led to improved outcomes


Alternate-Day Fasting Combined with Exercise: Effect on Sleep in Adults with Obesity and NAFLD

  • Does fasting and exercise improve sleep in metabolically unhealthy individuals? 
  • RCT: 80 adults with obesity and fatty liver disease randomized to:
    • Control (no intervention)
    • Fasting
    • Aerobic exercise 
    • Fasting + exercise
  • After 3 months, compared to control, fasting +/- exercise led to:
    • NO improvement in sleep quality or quantity 
    • NO reduction in sleep apnea risk


Assessment of the Anti-inflammatory Effects of NORFLO® ORO in Acute Relapses of HLA-B27-associated Autoimmune Uveitis: A Multicenter, Randomized, Placebo-controlled, Double-blind Clinical Study

  • Can curcumin reduce autoimmune disease related complications? 
  • RCT: Patients with acute anterior uveitis, randomized to: 
    • Placebo
    • Curcumin 
  • After 3 months, compared to placebo, curcumin led to: 
    • Reduced frequency of relapses 
    • No difference in symptom severity 


After Dinner Rest a While, After Supper Walk a Mile? A Systematic Review with Meta-analysis on the Acute Postprandial Glycemic Response to Exercise Before and After Meal Ingestion in Healthy Subjects and Patients with Impaired Glucose Tolerance

  • Does exercise before or after a meal lead to better blood sugar control?
  • Meta-analysis: 8 RCTs, 116 participants were randomized to:
    • Control (No exercise)
    • Exercise before or after a meal
      • Walking or bodyweight resistance training
  • Post-meal blood sugar was most improved with: 
    • Exercise after a meal (moderate effect size) 
    • 20 minutes of physical activity was sufficient
  • NO effect on blood sugar was seen from pre-meal exercise


Time of the day of exercise impact on cardiovascular disease risk factors in adults: a systematic review and meta-analysis

  • Is there an optimal time of day to exercise for cardiometabolic health?
  • Meta-analysis: 21 studies that randomized participants to:
    • Morning exercise
    • Evening exercise
  • Exercise time of day had NO impact on: 
    • Blood pressure
    • Blood sugar


Recovery from Exercise in Persons with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

  • How long do chronic fatigue patients take to recover from exercise?
  • Observational study: 78 chronic fatigue patients, 64 sedentary controls underwent:
    • 2-day cardiopulmonary exercise test (CPET)
      • Note: CPET is a maximal effort exercise test
  • Results showed the time needed to recover from exercise was:
    • ~2 days in sedentary controls
    • ~2 weeks in chronic fatigue patients


The Effect of Exercise Prescription on the Human Gut Microbiota and Comparison between Clinical and Apparently Healthy Populations: A Systematic Review

  • What is the best exercise routine to optimize the gut microbiota?
  • Systematic review: 28 studies, 800 participants 
    • All had their microbiotas assessed before and after exercise
  • The most effective exercise prescription for improving diversity of the microbiota is:
    • Type
      • Aerobic exercise
    • Intensity
      • Moderate-to-high intensity  
    • Frequency
      • ≥ 3 times/week for ≥ 8 weeks
    • Duration
      • 30-90 minutes/session


Association of Daily Step Patterns With Mortality in US Adults

  • How often do you need to walk to improve longevity?
  • Observational study: 3,101 middle-aged participants, walking ≥ 8,000 steps for:
    • 0 days/week 
    • 1-2 days/week
    • 3-7 days/week
  • After a 10 year follow up, all-cause mortality was reduced by:
    • 15% among those who walked 1-2 days/week 
    • 16.5% among those who walked 3-7 days/week 
  • This protective association plateaued around 3-4 days of walking ≥8,000 steps
  • “People may receive substantial health benefits even if a sufficient number of steps are taken on only a couple days of the week.”


Physical Activity Influences Cortisol and Dehydroepiandrosterone (Sulfate) Levels in Older Adults: A Systematic Review and Meta-Analysis

  • Does exercise reduce the effects of stress and aging?
  • Meta-analysis: 22 RCTs, adults ≥65 years of age randomized to:
    • Control
    • Exercise
      • Walking, qi gong, chair yoga, aerobic, strength, dance movement therapy
      • Most common duration was 3x/week for 45-60 minutes for 3 months 
  • Compared to control, regular exercise led to:
    • Reduced cortisol levels
    • Increased DHEA(S) levels
  • Note: Type of exercise did not influence the results


Effects of Mental Fatigue on Strength Endurance: A Systematic Review and Meta-Analysis

  • Does mental fatigue reduce exercise performance?
  • Meta-analysis: 7 studies, participants assigned to perform:
    • Resistance exercise 
    • Demanding cognitive task before resistance exercise
  • Compared to control, individuals who performed a cognitive task had:
    • Reduced exercise performance (small effect size)


Dose-response and temporal ergogenic effects of ginseng supplementation in athletes and active participants: A systematic review and meta-analysis

  • Does ginseng improve exercise performance?
  • Meta-analysis: 14 RCTs, participants randomized to:
    • Placebo
    • Ginseng
  • Compared to placebo, >300 mg/day of ginseng led to improved:
    • Vertical jump performance
  • Compared to placebo, ginseng did NOT improve:
    • Rate of perceived exertion 
      • How hard the exercise subjectively feels
    • VO2 max
    • Markers of muscle damage


Effect of nature prescriptions on cardiometabolic and mental health, and physical activity: a systematic review

  • What effect does spending time in nature have on various health outcomes? 
  • Meta-analysis: 28 clinical trials, participants were randomized to: 
    • Control 
    • Time in nature
      • Activities included:
        • Walking, gardening, reading, listening to music or meditating
      • Locations included
        • Forests, parks, hills, gardens, beaches or lakes
  • Compared to control, time in nature led to improvements in: 
    • Anxiety (large effect)
    • Depression (moderate effect) 
    • Blood pressure (-4.8 mm Hg) 
    • Daily step count (+900 steps/day) 


Sedentary Behaviour and Telomere Length Shortening during Early Childhood: Evidence from the Multicentre Prospective INMA Cohort Study

  • Does screen time in kids negatively affect markers of longevity? 
  • Observational study: 1,199 children assessed for screen time, categorized by:
    • Low screen time (0-1 hour/day)
    • High screen time (1.6-5 hours/day)
  • Compared to low screen time, high screen time was associated with: 
    • Shortened telomere length 


Associations between fetal or infancy pet exposure and food allergies: The Japan Environment and Children’s Study

  • Does exposure to pets reduce the risk of food allergies?
  • Observational study: 66,215 kids 
  • Exposure to pets either during pregnancy or infancy led to a reduced risk of: 
    • All food allergies by 14% 


Influence of hypovitaminosis D during pregnancy on glycemic and lipid profile, inflammatory indicators and anthropometry of pregnant and newborn

  • Does vitamin D deficiency affect pregnancy outcomes?
  • Systematic review: 19 observational studies involving pregnant women
  • Vitamin D deficiency was associated with:
    • Gestational diabetes
    • Pre-eclampsia
    • Gestational weight gain 


Associations between snoring and dental sleep conditions: A systematic review

  • Is snoring associated with other health concerns? 
  • Systematic review: 36 observational studies
    • Correlation between snoring and health outcomes assessed 
  • Snoring was associated with a higher probability of:
    • GERD
    • Sleep apnea 
    • Headaches
  • These associations were present even after adjusting for confounding variables, such as age, gender and BMI

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Episodes 107 & 108

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Psychobiotic Lactobacillus plantarum JYLP-326 relieves anxiety, depression, and insomnia symptoms in test anxious college via modulating the gut microbiota and its metabolism

  • Do probiotics reduce anxiety?
  • RCT: 60 college students with test anxiety were randomly assigned to:
    • Placebo
    • Probiotic
      • Lactobacillus plantarum JYLP-326, 15 billion CFU/day
  • After 3 weeks, compared to placebo, use of probiotics led to improved:
    • Anxiety
    • Depression
    • Insomnia


Synbiotic Supplementation Improves Quality of Life and Inmunoneuroendocrine Response in Patients with Fibromyalgia: Influence of Co-diagnosis with Chronic Fatigue Syndrome

  • Do synbiotics improve emotional health in fibromyalgia patients?
  • Clinical trial: 15 women with fibromyalgia, all treated with: 
    • Synbiotics
      • Lacto/bifido, 1 billion CFU/day
      • Fructo-oligosaccharide 200 mg/day
  • After 1 month, synbiotics led to improved: 
    • Depression
    • Stress & cortisol levels
    • Anxiety
    • Fatigue
  • Note: There was no placebo group. 


Heat-killed Lactobacillus helveticus improves mood states: a randomised, double-blind, placebo-controlled study

  • Can probiotics lead to a more positive mood?  
  • 58 healthy nursing students, randomized to: 
    • Placebo
    • Heat-killed probiotics 
      • Lactobacillus helveticus, 5 billion CFU
  • After 1 month, compared to placebo, probiotics led to improved: 
    • Friendliness
    • Vigor 
    • Feelings of relaxation
  • There was NO change in: 
    • Fatigue 
    • Low mood
    • Anxiety


Comparison of the effects of probiotics, rifaximin, and lactulose in the treatment of minimal hepatic encephalopathy and gut microbiota

  • Do gut-directed therapies improve liver health?
  • Clinical trial: 52 patients with hepatic encephalopathy were assigned to:
    • Rifaximin
    • Prebiotics
      • Lactulose
    • Probiotics
      • Bifidobacterium longum, Lactobacillus acidophilus, and Enterococcus faecalis 
  • After 1 month, all 3 treatments led to similar reversal of hepatic encephalopathy: 
    • Probiotics (58.8%)
    • Prebiotics (57.1%)
    • Rifaximin (45.5%)


Effects of various interventions on non-alcoholic fatty liver disease (NAFLD): A systematic review and network meta-analysis

  • Are probiotics effective for fatty liver disease?
  • Meta-analysis: 43 RCTs, 2,969 fatty liver patients assigned to:
    • Placebo
    • Probiotics
    • Curcumin
    • Lifestyle advice
      • Mediterranean diet, exercise, fasting 
  • Compared to other interventions, probiotics were the most effective for improving:
    • Liver enzymes (ALT)
    • Lipids (Total and LDL cholesterol)
  • “The most important finding of this study was that compared with diet and lifestyle, the use of probiotics had the best effect on improving NAFLD indicators


Therapeutic effect of probiotics on metabolic indices and clinical signs in age-related macular degeneration

  • Can probiotics improve macular degeneration?
  • RCT: 57 older adults with macular degeneration, randomized to:
    • Placebo
    • Probiotics
  • After 2 months, compared to placebo, probiotics led to:
    • NO difference in macular degeneration
    • Improved antioxidants status
    • Reduced oxidative stress


The effect of probiotics on postsurgical complications in patients with colorectal cancer: a systematic review and meta-analysis

  • Do probiotics improve post-surgical complications?
  • Meta-analysis: 13 studies involving patients undergoing colon cancer surgery
  • Probiotics led to reduced surgical complications, such as: 
    • Small intestinal obstruction (-87%)
    • Diarrhea (-68%) 
    • Sepsis (-59%) 
    • Surgical site infection (-47%) 
  • The most effective probiotic regimen was:
    • Dose < 1 billion CFU/day
    • >2 week treatment duration
    • Starting probiotics prior to surgery


Probiotics and Prebiotics in Subclinical Hypothyroidism of Pregnancy with Small Intestinal Bacterial Overgrowth

  • Can synbiotics improve SIBO and thyroid function?
  • Clinical trial: 32 pregnant women with SIBO and subclinical hypothyroidism on levothyroxine, treated with:
    • Synbiotics 
      • Lacto/bifido, Bacillus cereus and Enterococcus faecalis, 2.4 billion CFU/day
      • Inulin, 15 g/day 
  • After 3 weeks, synbiotics led to improved: 
    • TSH (2.46 → 1.63)
    • Methane positivity (34.4% → 12.5%
    • Overall GI symptoms
    • Diarrhea
    • Constipation


Dietary interventions for pediatric patients with functional abdominal pain disorders: a systematic review and network meta-analysis

  • Which gut-directed therapies are most effective for functional abdominal pain in children?
  • Meta-analysis: 29 RCTs involving children with functional abdominal pain
  • Compared to placebo, all 3 interventions were equally effective: 
    • Fiber 
    • Synbiotics
    • Probiotics
  • “The evidence of the efficacy of probiotics is more convincing than fiber and synbiotics when sample size and statistical power were considered”


Impact of Lactobacillus crispatus-containing oral and vaginal probiotics on vaginal health: a randomised double-blind placebo controlled clinical trial

  • Do probiotics improve vaginal dysbiosis? 
  • RCT: 89 patients with bacterial vaginosis, 93 vulvovaginal candidiasis patients, randomized to:
    • Placebo
    • Probiotics (Oral or Vaginal)
      • Lactobacillus crispatus, 30 billion CFU
  • After 3 months, probiotics led to improved vaginal: 
    • Dysbiosis
    • Discharge
    • Odor 
    • Itching/irritation
  • Note: Oral and vaginal probiotics both effective

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Children with functional gastrointestinal disorders with and without co-existing nausea: A comparison of clinical and psychological characteristics

  • Do worse GI symptoms lead to more psychological symptoms in children?
  • Observational study: 355 children with functional gastrointestinal disorders
  • Compared to children without nausea, those with nausea reported having worse:
    • Anxiety
    • Depression
    • Stress-related symptoms
    • Quality of life


Prebiotic Consumption Alters Microbiota but Not Biological Markers of Stress and Inflammation or Mental Health Symptoms in Healthy Adults: A Randomized, Controlled, Crossover Trial

  • Can prebiotics improve mood and other measures of health?
  • RCT: 24 healthy adults randomized to:
    • Control
    • Prebiotics
      • Fructo-oligosaccharides and galacto-oligosaccharides (10 g/day) 
  • After 1 month, compared to control, prebiotics did NOT improve:
    • Mood
    • Digestive function
    • Cortisol
    • Sleep quality
    • Inflammatory markers


Psychobiotic Effects on Anxiety Are Modulated by Lifestyle Behaviors: A Randomized Placebo-Controlled Trial on Healthy Adults

  • Do probiotics work better in patients with healthier lifestyles? 
  • RCT: 135 healthy adults, treated with:
    • Placebo
    • Probiotics
      • Lacto/bifido, 3 billion CFU/day
  • After 1 month, probiotics led to: 
    • NO difference in mood symptoms
  • However, subanalysis found probiotics did have a significant impact on mood in those who already engaged in healthy lifestyle behaviors, such as: 
    • Healthier diet
    • Exercise
    • Time in nature
    • Social support
  • “Healthy behaviors and probiotic intake was the single significant predictor of positive effects on anxiety, emotional regulation, and mindfulness in post-treatment outcomes.”


The effects of guar gum supplementation on lipid profile in adults: a GRADE-assessed systematic review, meta-regression and dose-response meta-analysis of randomised placebo-controlled trials

  • Can prebiotics improve cholesterol levels?
  • Meta-analysis: 19 RCTs involving patients assigned to:
    • Control
    • Guar gum
  • Compared to control, patients taking guar gum had improved:
    • Total cholesterol (-19.34 mg/dl)
    • LDL cholesterol (-16.19 mg/dl)
    • NO improvement in HDL or triglycerides


Meta-analysis: Post-COVID-19 functional dyspepsia and irritable bowel syndrome

  • Does COVID-19 increase the risk of functional GI disorders?
  • Meta-analysis: 10 observational studies, 2,763 COVID-19 patients and 1,235 controls
  • Compared to control, COVID-19 patients had an increased incidence of:
    • Functional dyspepsia (3% vs 2%)
    • IBS (9% vs 7%)
  • Note the small absolute increase in risk for functional GI disorders


Gut Microbiota Dysbiosis Correlates With Long COVID-19 at One-Year After Discharge

  • Is gut dysbiosis associated with long COVID?
  • Observational study: 130 long COVID-19 patients, 32 healthy controls
    • All underwent stool testing 
  • After 1 year, compared to healthy controls, long COVID-19 patients had:
    • Reduced gut microbiota diversity
    • Lower levels of SCFA-producing bacteria
  • Diarrhea and constipation were among the most common long-term symptoms


Efficacy and safety of probiotics in the treatment of irritable bowel syndrome: A systematic review and meta-analysis of randomised clinical trials using ROME IV criteria

  • What does the latest evidence say for treating IBS with probiotics?
  • Meta-analysis: 6 RCTs, IBS participants randomized to:
    • Placebo
    • Probiotics 
      • 9 different probiotic strains assessed
  • Compared to placebo, probiotics led to: 
    • Improved bloating (small effect) 
    • Reduced abdominal pain (large effect) 
    • NO difference in IBS symptom severity
    • NO difference in quality of life 


The epidemiology and psychological comorbidity of disorders of gut-brain interaction in Australia: Results from the Rome Foundation Global Epidemiology Study

  • What is the prevalence for various functional GI disorders?
  • Survey study: 2,036 adults 
  • 38.7% of participants fit the criteria for at least one functional GI disorder


Prevalence of small intestinal bacterial overgrowth in patients with gastroparesis: a systematic review and meta-analysis

  • How prevalent is SIBO in gastroparesis patients?
  • Meta-analysis: 6 studies, 385 gastroparesis patients assessed for SIBO
  • The prevalence of SIBO in gastroparesis patients was 41%
  • Note: This study doesn’t answer whether SIBO caused gastroparesis or gastroparesis predisposed patients to SIBO. 

Influence of proton pump inhibitor use on clinical outcomes of patients with inflammatory bowel disease

  • Do proton pump inhibitors worsen IBD clinical outcomes?
  • Observational study: 46,234 IBD patients
  • Proton pump inhibitor use was associated with: 
    • Greater need for new IBD medications (23% vs 21%)
    • Higher hospital admissions (8% vs 4%)
    • More surgeries (4% vs 2%)
  • “PPI use was associated with worse clinical outcomes in patients with IBD in the real-world setting.”


Bi-directional Relationship Between Celiac Disease and Liver Chemistries: A Systematic Review and Meta-Analysis

  • Can a gluten-free diet improve liver health in celiac patients?
  • Meta-analysis: 20 studies, 4,265 celiac patients underwent:
    • Liver enzyme testing
  • In celiac disease patients, a gluten-free diet normalized elevated liver enzyme levels in:
    • 83.1% of patients


Gut microbiota in Chinese and Japanese patients with cardiovascular diseases: a systematic review and meta-analysis

  • Is GI dysbiosis associated with worse cardiovascular health?
  • Meta-analysis: 11 studies, 960 participants
  • Compared to healthy controls, those with cardiovascular disease had:
    • Higher firmicutes (small effect size) 
    • Higher firmicutes/bacteroidetes ratio

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Thyroid & Hormones

Association between antithyroid peroxidase antibody and recurrent miscarriage

  • Are thyroid antibodies associated with miscarriage?
  • Observational study: 62 healthy women and 62 women with history of miscarriage underwent:
    • Screening for TPO-antibodies
  • Compared to healthy women, those with a history of miscarriage had:
    • Higher prevalence of anti-TPO antibodies (19.4% vs 6.5%)


The prevalence of subclinical hypothyroidism in a pre-diabetes population and an analysis of related factors

  • Does blood sugar dysregulation increase the risk of thyroid disease?
  • Observational study: 2,876 patients assessed for:
    • Pre-diabetes
    • Subclinical hypothyroidism
  • Compared to metabolically healthy individuals, those with pre-diabetes had a higher prevalence of: 
    • Subclinical hypothyroidism (26% vs 20%)

Prevalence of oral lichen planus in patients with hypothyroidism versus non-hypothyroidism – A case control study of 1000 cases

  • Is an oral inflammatory condition common in hypothyroid patients?
  • Observational study: 500 healthy controls, 500 hypothyroid patients
    • All assessed for oral lichen planus
  • Oral lichen planus was 2.4x more common in those with hypothyroidism
  • Note: It was not made clear whether or not hypothyroid patients also had thyroid autoimmunity. Oral lichen planus is also more common in those with Hashimoto’s [1].


Interindividual differences contribute to variation in microbiota composition more than hormonal status: A prospective study

  • Do female hormones influence the gut microbiota?
  • Observational study: 58 women who underwent hysterectomy
    • Gut microbiome was assessed
  • After 6 months, hysterectomy led to:
    • NO change in gut microbiota diversity

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Diet & Lifestyle

Effects of exercise intensity on gut microbiome composition and function in people with type 2 diabetes

  • How does exercise intensity influence the gut microbiota composition?
  • RCT: 12 patients with type 2 diabetes were randomized to perform:
    • Moderate-intensity aerobic exercise
    • High-intensity aerobic exercise
  • Compared to the high-intensity group, moderate intensity exercise led to increased:
    • Bifidobacterium
    • Akkermansia muciniphila
    • Butyrate-producing bacteria


Long-term effects of different exercise training modes on cytokines and adipokines in individuals with overweight/obesity and cardiometabolic diseases: A systematic review, meta-analysis, and meta-regression of randomized controlled trials

  • Does exercise reduce inflammation?
  • Meta-analysis: 106 RCTs, 8,642 overweight or obese individuals assigned to:
    • Control
    • Aerobic exercise
    • Resistance training
    • Aerobic + resistance training
  • Compared to control, all exercise interventions led to reduced:
    • Inflammatory biomarkers
      • CRP, IL-6 , IL-18, IL-20, TNF-α 


Effectiveness of yoga for major depressive disorder: A systematic review and meta-analysis

  • Can yoga improve major depression?
  • Meta-analysis: 34 RCTs, 2,341 patients with major depression randomized to:
    • Control
      • Medication, electroconvulsive therapy, waitlist, no treatment
    • Yoga
  • Compared to control, the yoga group had improved:
    • Depression symptoms (medium effect size)
    • Anxiety symptoms (small effect size)
  • Note: <4 sessions/week of yoga was most impactful on depression 


The effects of physical exercise on anxiety symptoms of college students: A meta-analysis

  • Does exercise improve anxiety?
  • Meta-analysis: 9 RCTs, 483 college students with anxiety randomized to:
    • Control
    • Exercise
      • Varied by study, included aerobic exercise, yoga, resistance
  • Compared to control, exercise led to:
    • Improved anxiety (moderate effect size)
      • Yoga (moderate effect size)
      • Aerobic (small effect size)
  • Resistance exercise had no impact on anxiety
  • Note: The most effective exercise regimens were:
    • ≥5 times/week frequency
    • 2-3 months duration
    • Moderate intensity


Interventions for reducing blood pressure in prehypertension: A meta-analysis

  • How does exercise compare to medication for improving blood pressure?
  • Meta-analysis: 101 RCTs, 20,176 subjects with high blood pressure
  • Compared to control, the most effective intervention for improving high blood pressure included:
    • High intensity interval training (-12 mmHg)
    • Diet, exercise + medication (-11 mmHg)
    • Aerobic exercise (-11 mmHg)


Sauna bathing, renal function and chronic kidney disease: cross-sectional and longitudinal findings from the KIHD study

  • Does sauna therapy negatively impact kidney function?
  • Observational study: 2,071 healthy men, categorized by sauna use: 
    • Infrequent (1x/week) 
    • Frequent (4-7x/week)
  • After 26 years, compared to infrequent use, frequent sauna use had:
    • NO impact on kidney function


Frequent sauna bathing may reduce chronic obstructive pulmonary disease risk: A prospective study

  • Can frequent sauna use prevent lung disease?
  • Observational study: 2,658 men, assessed for sauna use: 
    • Infrequent (≤2x/week)
    • Frequent (3-7x/week)
  • After 27 years, frequent sauna use was associated with a:
    • 38% reduced risk of COPD
  • Note: These benefits were seen even after adjusting for confounders, like smoking, heart disease, alcohol and diabetes


Effects of nutrition on metabolic and endocrine outcomes in women with polycystic ovary syndrome: an umbrella review of meta-analyses of randomized controlled trials

  • Which nutritional interventions can improve PCOS?
  • Umbrella review: 28 meta-analyses, PCOS patients randomized to:
    • Control
    • Nutritional intervention
      • Various supplements, dietary modification
  • Compared to control, nutritional interventions that improve PCOS the most include:
    • Low-carb diet
    • Vitamin D
    • Probiotics
    • Curcumin
    • Inositol
    • Fish oil


Cranberries for preventing urinary tract infections

  • Do cranberries prevent urinary tract infections?
  • Meta-analysis: 26 RCTs, 8,857 participants susceptible to UTIs, randomized to:
    • Control (placebo, no treatment)
    • Cranberry products
      • Supplement or cranberry juice
  • Compared to control, cranberry products led to:
    • 30% reduced risk of UTIs


Psychological Outcomes and Quality of Life of Fibromyalgia Patients with Vitamin D Supplementation-A Meta-Analysis

  • Does vitamin D improve quality of life in fibromyalgia patients? 
  • Meta-analysis: 8 studies, 694 fibromyalgia patients, assigned to: 
    • Control
    • Vitamin D
      • 50,000 IU/week 
  • Vitamin D supplementation led to improvements in: 
    • Physical function 
    • Social function 
    • Emotional health
    • Quality of life 
  • No change in:
    • Pain levels
    • Depression


Delayed Eating Schedule Raises Mean Glucose Levels in Young Adult Males: a Randomized Controlled Cross-Over Trial

  • How does meal timing affect blood sugar levels?
  • RCT: 8 healthy males were randomized to eat meals:
    • Early
      • 8:30am, 1:30pm, 7:30pm
    • Late
      • 12:00pm, 5:00pm, 11:00pm
  • Compared to early meal times, late meal times led to:
    • Higher 24-hour blood sugar (99 mg/dL vs 91 mg/dL)


The impact of 12 modifiable lifestyle behaviours on depressive and anxiety symptoms in middle adolescence: prospective analyses of the Canadian longitudinal COMPASS study

  • What lifestyle factors are associated with less teenage anxiety and depression?
  • Observational study: 24,274 high school students
  • Participants experienced less anxiety and depression when they:
    • Consumed ≥2-3 servings of meat/protein sources daily 
    • Avoided sugar-sweetened beverages
    • Watched <2 hours screen time per day 
    • Slept for 8-10 hours  
    • Did not consume cannabis


Potential reversal of biological age in women following an 8-week methylation-supportive diet and lifestyle program: a case series

  • Can lifestyle interventions reverse biological aging? 
  • Case series: 6 healthy women, all treated with: 
    • Nutrient-dense diet 
    • Sleep 
      • At least 7 hours/night
    • Exercise
      • 30 minutes 5x/week
    • Breathing exercises 
    • Probiotics 
      • Lactobacillus plantarum, 20 billion CFU/day
    • Greens powder 
  • After 2 months, participants experienced a reduction in: 
    • Biological age (-4.6 years) 
      • ….adherence rates were 82%


Polyunsaturated fatty acids (PUFA) for attention deficit hyperactivity disorder (ADHD) in children and adolescents

  • Does fish oil supplementation improve ADHD?
  • Meta-analysis: 37 RCTs, 2,374 children with ADHD randomized to:
    • Control 
      • Placebo, psychotherapy, medication
    • Polyunsaturated fatty acid (PUFA) supplementation
  • Compared to placebo, PUFA supplementation did NOT improve:
    • Parent-rated ADHD symptoms
    • Inattention
    • Hyperactivity


Effects of long-chain omega-3 polyunsaturated fatty acids on reducing anxiety and/or depression in adults; A systematic review and meta-analysis of randomised controlled trials

  • Can omega-3 fatty acids improve depression?
  • Meta-analysis: 10 RCTs, 1,426 participants, randomized to: 
    • Placebo
    • Omega 3 fatty acid supplements
      • Varied by EPA/DHA content
  • After 2-3 months, omega-3 supplementation led to reduced: 
    • Depression severity (small effect) 
      • …especially at a dose of 1-2 g/day of EPA
      • >2 g/day NOT effective


Omega-3 fatty acids supplements for dry eye – Are they effective or ineffective?

  • Do omega-3 fatty acids improve dry eye?
  • RCT: 470 participants with dry eye symptoms were randomized to:
    • Placebo
    • Omega-3 fatty acids
      • 1,440 mg of EPA, 960 mg DHA/day
  • After 6 months, compared to placebo, the omega-3 group had improved:
    • Dry eye symptoms
    • Tear production


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