Episodes 105 & 106
Probiotics
- 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)
- 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
- 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)
- 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
- 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
- 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
- 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
- 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
- Placebo + Probiotics
- After 3 months, compared to probiotics alone, melatonin + probiotics led to:
- Greater reduction in abdominal pain
- 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
- 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)
GI
- 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
- 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%)
- 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
- Control patients
- 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%)
- 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
- 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
- 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
- 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
- Observational study: 56 patients with functional dyspepsia, 30 controls, all participants underwent
- 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
- 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
- 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
Thyroid & Hormones
- 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
- 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
- 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
- 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
- Nigella sativa
- 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)
- Subclinical hyperthyroidism (1.5x increased risk)
- 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
- 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
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
- 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
- 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
- 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
- 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
- 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
- Control
- 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.’
- 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
- 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
- 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
- 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
- 2-day cardiopulmonary exercise test (CPET)
- Results showed the time needed to recover from exercise was:
- ~2 days in sedentary controls
- ~2 weeks in chronic fatigue patients
- 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
- Type
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.”
- 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)
- 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
- Rate of perceived exertion
- 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
- Activities included:
- 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)
- 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
- 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%
- 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
Episodes 107 & 108
Probiotics
- 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
- 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
- Synbiotics
- After 1 month, synbiotics led to improved:
- Depression
- Stress & cortisol levels
- Anxiety
- Fatigue
- Note: There was no placebo group.
- 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
- 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%)
- 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”
- 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
- 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
- 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
- Synbiotics
- After 3 weeks, synbiotics led to improved:
- TSH (2.46 → 1.63)
- Methane positivity (34.4% → 12.5%)
- Overall GI symptoms
- Diarrhea
- Constipation
- 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”
- 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
GI
- 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
- 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
- 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.”
- 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
- 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
- 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
- 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.
- 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.”
- 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
- 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
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%)
- 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%)
- 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].
- 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
Diet & Lifestyle
- 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
- 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
- Inflammatory biomarkers
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
- Control
- 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)
- Improved anxiety (moderate 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)
- 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
- 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
- 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
- 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
- Early
- Compared to early meal times, late meal times led to:
- Higher 24-hour blood sugar (99 mg/dL vs 91 mg/dL)
- 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
- 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%
- Biological age (-4.6 years)
- 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
- Control
- Compared to placebo, PUFA supplementation did NOT improve:
- Parent-rated ADHD symptoms
- Inattention
- Hyperactivity
- 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
- Depression severity (small effect)
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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