Episodes 97 & 98
Probiotics
- Do probiotic lozenges improve oral health?
- RCT: N = 60 participants with gingivitis, treated with:
- Placebo + teeth cleaning
- Probiotic + teeth cleaning
- Bifidobacterium animalis lozenge (2 billion CFU/day)
- After 2 months, compared to placebo, probiotics led to reduced:
- Gingivitis prevalence (33% probiotic vs 63% placebo)
- Gum bleeding
- Can probiotics improve oral health?
- Meta-analysis: 10 RCTs, participant received:
- Chlorhexidine
- Probiotic mouthwash
- Probiotics varied, included lactobacillus, streptococcus spp
- After 1 month, either treatment led to similar improvements in:
- Gingivitis
- Plaque formation
- “Probiotics were an acceptable alternative to conventional chlorhexidine in improving periodontal health”
- Do probiotics improve muscle mass and strength in adults?
- MA: 24 RCTs, adults received:
- Placebo
- Probiotics
- Strains varied, included lactobacillus, bifidobacterium, bacillus spp, streptococcus
- Compared to placebo, probiotics led to improved:
- Muscle strength (medium effect)
- Muscle mass (small effect)
- Can probiotics help with weight loss?
- RCT: N = 100 overweight participants received:
- Placebo
- Probiotics
- Lactobacillus plantarum (20 billion CFU/day)
- After 3 month, probiotics led to reduced:
- Weight (-2 lbs)
- Visceral fat
- Insulin levels
Efficacy of probiotics on nonalcoholic fatty liver disease: A meta-analysis.
- Do probiotics improve liver function in those with fatty liver disease?
- Meta-analysis: 21 RCTs, N = 1,037 participants with fatty liver disease, randomized to
- Control
- Probiotics
- (varied by study, included lactobacillus, bifidobacterium, streptococcus thermophilus)
- Compared to controls, probiotics led to improved:
- Liver fat content
- Liver enzymes (AST, ALT, GGT)
- ALT ( −8.5 U/L)
- AST (−6.8 U/L)
- GGT (−5.9 U/L)
- Triglycerides (−17.3 mg/dL)
- HDL-C (+3.4 mg/dL)
- Probiotics had NO effect on:
- Body composition
- Blood sugar
- Inflammatory markers
- Probiotics improved liver function to a greater extent when treated for more than 3 months
- Do probiotics reduce the risk of infants developing allergies?
- Clinical trial: N = 83 infants with a family history of allergies were treated with:
- Control
- E. coli O83
- Given 2 days post-delivery
- After 10 years, compared to control, probiotics led to:
- Lower incidence of allergies (20% probiotics vs 34% control)
- NO effect on the gut microbiome
- “Early postnatal E. coli supplementation appears to lower allergy incidence in children of allergic mothers. It seems that the beneficial effect of e. coli is mediated via modulation of dendritic cells without impacting the microbiota composition.
Strain-Specificity of Probiotics in Pediatrics: A Rapid Review of the Clinical Evidence.
- Does strain-specificity matter when using probiotics?
- Review: 23 RCTs, children who used probiotics for various conditions:
- Diarrhea, H. pylori atopic dermatitis, respiratory tract infections, necrotizing enterocolitis
- When comparing different strains of probiotics on treating the same condition, the majority of the evidence found NO difference in effectiveness between probiotic strains of the same species
- “This rapid review demonstrates insufficient clinical evidence to support or refute the claim that probiotic effects in children are strain-specific.”
- How do probiotics compare to antibiotics for improving surgical outcomes in those with colon cancer?
- Meta-analysis: 20 RCTs, N = 3,726 participants with colorectal cancer were randomized to:
- Placebo + usual care
- Antibiotics + usual care
- Probiotics and/or prebiotics + usual care
- Probiotics varied, primarily included lactobacillus, bifidobacterium
- ONLY antibiotics led to reduced:
- Post-surgical infections
- Do synbiotics improve hypothyroidism?
- RCT: N = 51 participants with hypothyroidism (overt and subclinical), currently taking levothyroxine, were randomized to:
- Placebo
- Synbiotic
- FOS + lacto/bifido, streptococcus (1 billion CFU/day)
- After 2.5 months, compared to placebo, synbiotics led to:
- NO change in TSH or fT4
- NO change in depression
- Greater feeling of well-being
- Improved mental health
- Reduced pain levels
- Can soil-based probiotics eradicate pathogenic bacteria?
- RCT: N = 115 healthy participants colonized with staphylococcus aureus, randomized to:
- Placebo
- Soil-based probiotics
- Bacillus subtilis (5 billion CFU)
- After 1 month, compared to placebo, probiotics led to reduced:
- Stool staph aureus colonization (-97%)
- Nasal staph aureus colonization (-65%)
- “Soil-based probiotics eliminated more than 95% of the total S aureus colonizing the human body without altering the microbiota.”
- Do soil based probiotics improve recovery in COVID-19 patients?
- Observational study: N = 120 participants with mild COVID-19, treated with:
- Control (no probiotics)
- Soil-based probiotics
- 4 billion CFUs/day
- Compared to the control group, those taking probiotics ≥ 1 month prior to infection experienced:
- Shorter symptom duration (~2 days shorter)
- Shorter fever duration (1.2 days shorter)
- Fewer digestive symptoms
- “Participants in the probiotic group were 1.68 times more likely to have a faster symptom resolution compared with controls.”
GI
- Do symptom-guided elimination diets improve IBS?
- Clinical trial: N = 65 participants with IBS, with or without IBD, received:
- Symptom-guided personalized elimination diet
- After 2 months, the diet led to:
- Improved QoL in 89%
- Improved IBS symptoms in 70%
- Clinical remission in 68%
- Is fecal microbiota transplantation an effective therapy for IBS?
- Meta-analysis: 7 RCTs, N = 470 participants with IBS, received:
- Placebo
- Fecal microbiota transplantation
- Fecal microbiota transplantation led to:
- NO IBS symptom improvement
- 26x higher efficacy for improving IBS symptoms when delivered in the upper GI tract
- Is there a high prevalence of pancreatic insufficiency in children with IBD?
- Observational study: N = 74 children with IBD, all underwent endoscopic pancreatic function testing
- 57% of children were diagnosed with exocrine pancreatic insufficiency
Efficacy of elimination diets in eosinophilic esophagitis: a systematic review and meta-analysis.
- Is testing needed for dietary management of eosinophilic esophagitis?
- Meta-analysis: 34 studies, N = 1,762 participants with eosinophilic esophagitis, treated with:
- Test-based elimination diets
- Empiric elimination diets
- Six-food, four-food or one-food
- Compared to test-based elimination diets, empiric elimination diets led to greater clinical response rates:
- Six-food (93%)
- Four-food (74%)
- One-food (87.1%)
- Test-based (69%)
- Does fiber improve diarrhea in young children?
- RCT: N = 92 children (1-3 years old) with watery diarrhea, received:
- Placebo
- Soluble fiber supplement (Fibersol-2)
- After 3 days, fiber supplementation had NO effect on diarrhea:
- Duration
- Frequency
The Impact of Intermittent Fasting on Patients With Suspected Gastroesophageal Reflux Disease.
- Does intermittent fasting improve acid reflux?
- Clinical trial: N = 25 participants with acid reflux underwent intermittent fasting
- 8 hour eating window
- After 2 days, intermittent fasting led to improved:
- Heartburn
- Reflux
- Compliance rates were low (36% completed study)
Successful Dietary Therapy in Paediatric Crohn’s Disease is Associated with Shifts in Bacterial Dysbiosis and Inflammatory Metabotype Towards Healthy Controls.
- Is successful dietary treatment of IBD associated with improved dysbiosis?
- Observational study: N = 54 children in remission from IBD, 26 healthy controls
- Remission induced by enteral nutrition + elimination diet
- After 3 months, diet-induced remission was associated with:
- Reduced opportunistic gut flora
- No association between remission and increased short chain fatty acids
- Do those with chronic urticaria have altered gut flora?
- Observational study: N = 15 participants with chronic urticaria, 15 healthy controls
- Chronic urticaria was associated with the following microbiota composition:
- Increased alpha-diversity
- Increased firmicutes
- Decreased bacteroidetes
- Decreased proteobacteria
- Does air pollution affect the health of the gut?
- Observational study: 100 participants with ulcerative colitis, 75 participants with IBS
- Compared to areas of low air pollution, those from highly polluted areas had:
- Greater mucosal inflammation
- Increased opportunistic bacteria
- Higher Proteobacteria
- Decreased beneficial bacteria
- Lower Bacteroidetes
Thyroid & Hormones
- Does levothyroxine improve fitness in older adults with subclinical hypothyroidism?
- RCT: N = 267 older participants with subclinical hypothyroidism, randomized to:
- Placebo
- Levothyroxine
- Levothyroxine normalized TSH, but had NO effect on muscle:
- Strength
- Mass
- Function
- Does a low carbohydrate diet improve testosterone and associated symptoms?
- RCT: 18 men with low testosterone and metabolic syndrome were randomized to:
- Control
- Low-carb diet
- After 3 months, the low-carb diet led to:
- Increased total testosterone (+81 diet vs +10 ng/dl control)
- Improved erectile dysfunction
- Greater weight loss (-10 lbs vs -2 lbs)
Diet & Lifestyle
Calcium and vitamin D for increasing bone mineral density in premenopausal women.
- Do calcium and vitamin D supplements improve bone health in premenopausal women?
- Review: 7 RCTs, N = 941 healthy premenopausal women, randomized to:
- Placebo
- Calcium and/or vitamin D
- NO intervention improved:
- Hip or spine bone mineral density
- Note: None of these women had osteopenia/osteoporosis
- Does exercise increase bone mineral density in postmenopausal women?
- Meta-analysis: 80 clinical trials, N = 5,581 menopausal women +/- osteoporosis received:
- Control
- Exercise
- Varied by study, included aerobic, resistance, aerobic + resistance, tai chi, jumping
- After a minimum of 6 months, exercise led to:
- Greater bone mineral density (small effect)
- Do mindfulness-based interventions improve the mental health of menopausal women?
- Meta-analysis: 13 RCTs, N = 1,138 menopausal participants treated with:
- Control
- Mindfulness interventions
- Meditation, yoga, mindfulness-based stress reduction
- Mindfulness interventions led to:
- Decreased stress (large effect size)
- NO effect on:
- Anxiety
- Depression
- Does exercise improve symptoms of major depressive disorder?
- Meta-analysis: 41 RCTs, 2,264 participants with major depression received:
- Control
- Exercise
- Aerobic and/or strength training
- Exercise led to:
- Reduced depressive symptoms (large effect size)
- Number needed to treat (NNT) comparison:
- Exercise NNT = 2
- Antidepressant medication NNT = 7
- Does vitamin D supplementation lead to more favorable COVID-19 outcomes?
- Meta-analysis: 5 RCTs, participants with COVID-19 treated with:
- Control
- Placebo or low-dose vitamin D
- Vitamin D
- Dose varied, between 5,000-200,000 IU/day
- Control
- Vitamin D supplementation led to reduced risk of:
- ICU admission (small effect)
- Death (small effect)
- Does vitamin D improve COVID-19 recovery times?
- RCT: N = 171 participants with mild-moderate COVID-19 received:
- Placebo
- Vitamin D
- 12,000 IU x 3 days, then 2,400 IU x ~1 month
- After 1 month, vitamin D led to:
- Faster resolution of respiratory symptoms (4 days faster)
- NO difference in total symptom recovery time
- Does resistance training improve clinical outcomes in Parkinson’s disease?
- MA: 16 studies, N = 761 participants with Parkinson’s received:
- Control
- Balance training, modified fitness counts, no treatment
- Progressive resistance training
- Control
- Resistance training led to improved:
- Muscle strength (large effect)
- Quality of life (large effect)
- Gait quality (medium effect)
- There was NO effect on:
- Balance
- Gait speed
- Does cold water immersion immediately after exercise improve recovery?
- Meta-analysis: 20 RCTs, N = 357 healthy participants performed a single-bout of exercise, then were treated with either:
- Control
- Passive recovery or active recovery
- Cold water immersion
- Control
- Cold water therapy after exercise led to immediate improvements in:
- Muscle soreness (medium effect)
- Perceived exertion (medium effect)
- Serum lactate (medium effect)
Meditation and Yoga for Irritable Bowel Syndrome: A Randomized Clinical Trial.
- Does yoga improve clinical outcomes in IBS patients?
- RCT: N = 79 participants with IBS, treated with:
- Control
- Yoga
- Included meditation, breath work and yoga
- After 2 months, compared to control, yoga led to greater improvements in:
-
- IBS symptoms scores
- -55 points yoga vs -23 points control
- Quality of life
- Fatigue
- Stress
- IBS symptoms scores
- Do nutritional interventions improve sarcopenia?
- Meta-analysis: 3 studies, N = 637 participants with muscle wasting received:
- Placebo
- Nutritional Shake
- Whey protein (20 g), Leucine (3-4 g), Vitamin D (800 IU)
- Consumed 1-2x/day
- After 2-3 months, compared to placebo, the nutritional shake alone led to:
- Increased muscle mass
- NO effect on:
- Muscle strength
- Physical performance
- The addition of exercise to the nutritional intervention led to improved:
- Muscle strength
- Physical performance
Episodes 99 & 100
Probiotics
- Do probiotics help prevent pregnancy complications?
- Meta-analysis: 6 RCTs of pregnant women, randomized to:
- Control
- Probiotics
- Probiotics had NO effect on:
- Incidence of gestational diabetes
- Fasting glucose
- Preeclampsia
Probiotics for management of functional abdominal pain disorders in children
- Do probiotics improve digestive symptoms in children?
- Meta-analysis: 18 RCTs, 1,309 children with functional abdominal pain, randomized to:
- Control
- Probiotics or synbiotics
- Formulas varied, included bifidobacterium, lactobacillus
- Compared to control, probiotics or synbiotics led to:
- Greater treatment success (49% probiotics vs 34% control)
- No effect on complete resolution of pain
- Do probiotics improve dyslipidemia?
- RCT: 50 participants with elevated cholesterol received:
- Placebo
- Probiotics
- Lactobacillus paracasei, 10 billion CFU
- After 3 months, compared to placebo, probiotics led to reduced:
- LDL-C (-18 mg/dl probiotic vs +12 mg/dl placebo)
- Oxidative stress
- Malondialdehyde
- Inflammation
- TNF-α
- There was NO effect on:
- Total cholesterol
- HDL-C
- Triglycerides
- Do probiotics improve tolerance to infant formula?
- Observational study: 1,731 healthy infants, categorized by:
- Breast-fed only
- Formula only
- Formula + probiotic
- Lactobacillus reuteri
- Compared to standard formula, probiotic-containing formula was associated with:
- Better tolerance to formula
- Less difficulty passing stool
- Reduced colic
- Less spitting up
- Note: Digestive-related symptoms were similar when comparing formula + probiotics vs breast-fed infants
- Can soil-based probiotics treat a serious GI infection?
- Clinical trial: 263 participants with recurrent C. Diff infection, all treated with:
- Soil-based probiotics
- Firmicutes spores
- Soil-based probiotics
- After 6 months, soil-based probiotics led to:
- Reduced C. diff recurrence rates (14% of participants had recurrence)
- Adverse events in 54%
- Mild-to-moderate GI side effects
- Note: No placebo group
- Do probiotics improve growth and neurological development in preterm infants?
- Meta-analysis: 30 RCTs, 4,817 preterm infants treated with:
- Control
- Probiotics
- Varied by study, included lactobacillus, bifidobacterium, streptococcus thermophilus, saccharomyces boulardii
- Compared to control, probiotics led to improved:
- Short-term weight gain (small effect)
- NO effect on:
- Length
- Head circumference
- Neurological development
- Do probiotics improve outcomes in critically ill patients?
- Meta-analysis: 9 RCTs, 860 critically ill adults received:
- Control
- Probiotics
- Strains varied across studies, including lactobacillus, bacillus
- Compared to controls, probiotics led to:
- 27% reduced risk of hospital-acquired infections
- NO effect on mortality risk
GI
- Does FODMAP consumption worsen symptoms in functional GI disorders?
- Observational study: 173 participants with IBS, functional diarrhea or constipation, 119 healthy controls
- All monitored for FODMAP intake
- Compared to all other groups, IBS participants experienced worse GI symptoms after FODMAP consumption, including:
- Abdominal pain
- Bloating
- Are commonly prescribed medications linked to an altered intestinal microbiome?
- Observational study: 4,013 participants with dysbiosis, 4,013 healthy controls
- All were assessed for medication intake
- The following medications were associated with an increased risk of dysbiosis:
- Decongestants (45% increased risk)
- Antibiotics (28%)
- Proton pump inhibitors (39%)
- Note: Unclear from the study how they diagnosed dysbiosis
- Do children with ADHD have higher levels of intestinal permeability markers?
- Observational study: 40 children with ADHD, 39 healthy controls
- All underwent serum testing for intestinal permeability
- Those with ADHD had elevated serum:
- Zonulin (37 ADHD vs 8 ng/mL controls)
- Occludin (2.4 vs 0.6 ng/mL)
- Note: did not report on GI symptoms
- Do those with IBS have signature alterations in the gut flora?
- Observational study: 567 participants with IBS, 487 healthy controls
- All underwent 16S rRNA microbial stool analysis
- Compared to healthy controls, those with IBS had:
- Intestinal dysbiosis
- Lower alpha-diversity
Butyrate Ameliorates Insufficient Sleep-Induced Intestinal Mucosal Damage in Humans and Mice
- Is insufficient sleep associated with worse gut health?
- Observational study: 454 college students with insufficient sleep (< 7 hours/night)
- All underwent 16S rRNA microbial stool analysis
- Those who slept less than 7 hours had:
- Higher prevalence of gut disorders (42%)
- Decreased Faecalibacterium
- Decreased butyrate levels
Thyroid & Hormones
- Does tighter control of TSH levels improve pregnancy and fertility outcomes?
- Observational study: 548 women with subclinical hypothyroidism, categorized by TSH levels on levothyroxine:
- Low-normal TSH (< 2.5 mIU/L)
- High-normal TSH (2.5-4.2 mIU/L)
- There was NO difference between the low-normal and high-normal TSH groups in:
- Pregnancy rates
- Miscarriage rates
Hypothyroidism: The difficulty in attributing symptoms to their underlying cause
- Should subclinical hypothyroidism be treated with levothyroxine?
- Review paper: Subclinical hypothyroid patients had:
- Similar rates of “hypothyroid-related” symptoms compared to euthyroid populations
- TSH levels independent of symptom severity
- Symptoms non-responsive to levothyroxine
- Discontinuation of LT4 results in normalized thyroid function in around 1/3rd of those with subclinical hypothyroidism
- Does Hashimoto’s thyroiditis increase the risk of systemic lupus?
- Observational study: 15,512 participants with Hashimoto’s thyroiditis, 31,024 controls
- Those with Hashimoto’s had:
- 4-5x increased risk for developing systemic lupus
- Is vitamin D status linked to thyroid autoimmunity?
- Observational study: 57 women with thyroid autoimmunity, 41 controls
- There was NO association between vitamin D levels and:
- Thyroperoxidase antibodies
- Thyroglobulin antibodies
- TSH and fT4
Diet & Lifestyle
Does Caffeine Increase Fat Metabolism? A Systematic Review and Meta-Analysis
- Does caffeine help increase fat metabolism?
- Meta-analysis: 94 studies looked at the effect of caffeine on fat metabolism
- Based on various biomarkers
- Caffeine intake led to:
- Increase fat metabolism (small effect)
- Note: This study looked at biomarkers for fat metabolism, which doesn’t always correlate with outcome data. However, a 2019 meta analysis found caffeine intake has a small effect on the clinical outcome of weight loss.
- Does exercise improve fatty liver disease?
- Meta-analysis: 14 RCTs, 551 participants with non-alcoholic fatty liver disease, randomized to:
- Control (no exercise)
- Exercise
- Compared to control, exercise led to:
- ≥30% reduction in liver fat
- Independent of weight loss
- ≥30% reduction in liver fat
- Only ≥150 minutes of moderate intensity exercise per week led to greatest benefit
- Does a low-carb diet improve mental health outcomes?
- Meta-analysis: 8 RCTs, 590 participants with depression or anxiety, randomized to:
- Control
- Low-carb diet
- A low-carb diet led to:
- NO effect on depression
- Increased anxiety (small effect)
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