health

Oxygen Utilization Improvement

See how Oxygen Utilization Improvement is framed as a health effect and decide what context matters most.

22Practices

These are research findings, not promises. Most options have little evidence, and results differ from person to person.

What may help

What studies found for each option, best evidence first.

22 options:2 good evidence5 some evidence2 mixed8 not enough evidence2 not tested in people1 personal stories only2 no benefit found

What studies foundSize of effect

CardiopracticeGood evidence it helpsSize of effect: Not known
Good human studies found a benefit, and they mostly agree. This is about what studies measured, not a cure.
All 6 studies with a clear result found a benefit. Strongest study: a pooled analysis of several trials.
Open the Cardio page
CyclingpracticeGood evidence it helpsSize of effect: Small
Good human studies found a benefit, and they mostly agree. This is about what studies measured, not a cure.
All 6 studies with a clear result found a benefit. Strongest study: a pooled analysis of several trials.
Pooled analyses whose designs were not recorded found a small improvement in VO2peak with HIIT. A separate pooled analysis found a small increase in maximal oxygen consumption with e-cycling, involving 78 people in its outcome analysis.
Open the Cycling page
High-Intensity Interval Training (HIIT)practiceSome evidence it helpsSize of effect: Small
Some human studies found a benefit. More research could change this.
6 of 7 studies found a benefit; 1 found none. Strongest study: a pooled analysis of several trials.
A pooled analysis of randomized trials involving 713 people found an increase in peak heart rate, with considerable heterogeneity. A review of randomized trials involving 261 people also reported a small improvement in peak VO₂.
Open the High-Intensity Interval Training (HIIT) page
BreathworkpracticeSome evidence it helpsSize of effect: Not known
Some human studies found a benefit. More research could change this.
7 of 8 studies found a benefit; 1 found none. Strongest study: a randomized controlled trial.
In a 2022 randomized trial of 291 people, arterial oxygen pressure on postoperative day 5 was higher with breathing exercises than in the control group (106.4 vs. 83.00 mmHg). A separate 2025 trial found higher blood oxygen saturation on the first day in the cardiovascular surgery unit.
Open the Breathwork page
Indoor RowingpracticeSome evidence it helpsSize of effect: Not known
Some human studies found a benefit. More research could change this.
All 4 studies with a clear result found a benefit. Strongest study: a randomized controlled trial.
Open the Indoor Rowing page
SwimmingpracticeSome evidence it helpsSize of effect: Not known
Some human studies found a benefit. More research could change this.
All 3 studies with a clear result found a benefit. Strongest study: a randomized controlled trial.
A randomized trial of 36 people found fitness test levels improved after exercise. A separate randomized trial of 21 reported that SmO2 decreased at T400, so the reported findings do not point to a single direction of change in oxygen use.
Open the Swimming page
Tabata TrainingpracticeSome evidence it helpsSize of effect: Not known
Some human studies found a benefit. More research could change this.
All 2 studies with a clear result found a benefit. Strongest study: a randomized controlled trial.
Open the Tabata Training page
Ice Bath / Cold PlungepracticeMixed resultsSize of effect: Not known
Studies disagree: some found a benefit, others found none. Do not count on it.
3 of 5 studies found a benefit; 2 found none. Strongest study: a randomized controlled trial.
An RCT involving 16 people found higher blood oxygen saturation with cold-water immersion than control at 10 min, 15 min, and 20 min. In another RCT involving 30 people, muscle oxygen consumption increased after training in the cold-water immersion group but not the active-control group.
Open the Ice Bath / Cold Plunge page

Hot BathpracticeMixed resultsSize of effect: Not known
Studies disagree: some found a benefit, others found none. Do not count on it.
3 of 5 studies found a benefit; 2 found none. Strongest study: a randomized controlled trial.
A trial of 21 healthy people found that water immersion increased the oxygen-uptake asymptote by +16%, +13% and +17%, depending on the measure, and increased area under the curve by +27%, +18% and +20%. Another trial found lower oxygen consumption during brief submaximal runs within 24 h after exercise with hot-water immersion at 41°.
Open the Hot Bath page
Tai ChipracticeNot enough evidence
Too few or too small studies to know if it works.
The one study found a benefit. Strongest study: a pooled analysis of several trials.
Open the Tai Chi page
TENS / EMS TherapypracticeNot enough evidence
Too few or too small studies to know if it works.
The one study found a benefit. Strongest study: a pooled analysis of several trials.
Pooled analyses whose designs were not recorded found improved LSAT with TENS compared with control in people with sleep apnea.
Open the TENS / EMS Therapy page
Foam RollingpracticeNot enough evidence
Too few or too small studies to know if it works.
All 2 studies with a clear result found a benefit. Strongest study: a randomized controlled trial.
In a trial of 25 participants, muscle oxygen saturation increased after exercise by 9.5%, 12%, and 8.8% in the reported stretching-and-rolling and stretching conditions. The finding was not specific to foam rolling, because an increase was also reported with static stretching alone.
Open the Foam Rolling page
DancepracticeNot enough evidence
Too few or too small studies to know if it works.
The one study found a benefit. Strongest study: a randomized controlled trial.
Open the Dance page
Red Light Therapy (Photobiomodulation)practiceNot enough evidence
Too few or too small studies to know if it works.
The one study found a benefit. Strongest study: a randomized controlled trial.
A trial involving 32 women with obesity found that VO2 increased by 7% after photobiomodulation compared with before treatment.
Open the Red Light Therapy (Photobiomodulation) page
PilatespracticeNot enough evidence
Too few or too small studies to know if it works.
The one study found a benefit. Strongest study: a randomized controlled trial.
A 2023 trial of 30 participants
Open the Pilates page
FastingpracticeNot enough evidence
Too few or too small studies to know if it works.
The one study found a benefit. Strongest study: a randomized controlled trial.
In a randomized controlled trial of 16 people with overweight, a 3-week alternate-day fasting regimen reduced blood pressure and MVO2 and improved MFR.
Open the Fasting page
Finnish SaunapracticeNot enough evidence
Too few or too small studies to know if it works.
The one study found a benefit. Strongest study: a non-randomized trial.
In a quasi-experimental study of 15 people with heart failure, peak respiratory oxygen uptake increased from 13.3 +/- 1.8 to 16.3 +/- 2.1 mL/kg/min.
Open the Finnish Sauna page
Pursed-Lip BreathingpracticeNot tested in people
Only tested in animals, cells or theory. Results like these often do not carry over to people.
The one study found a benefit.
The proposed explanation is that Pursed-Lip Breathing prolongs exhalation, reduces air trapping, and improves ventilation-perfusion matching, which may support oxygen saturation and ease breathlessness during exertion. This is a rationale rather than a finding from human studies.
Open the Pursed-Lip Breathing page
Latin Dance FitnesspracticeNot tested in people
Only tested in animals, cells or theory. Results like these often do not carry over to people.
The one study found a benefit.
Dance fitness is described as improving VO2max and oxygen extraction at the muscle level.
Open the Latin Dance Fitness page
Coherent BreathingpracticeOnly personal stories
Only people's own stories online. No study has tested it.
Based on one study.
Open the Coherent Breathing page
Strength TrainingpracticeNo benefit found
Studies looked for a benefit and did not find one.
The one study found no benefit. Strongest study: a pooled analysis of several trials.
The studies did not support an improvement in oxygen utilization: a pooled analysis whose study designs were not recorded found VO2max improvements that did not reach statistical significance among 203 people in its analysis.
Open the Strength Training page
Hot YogapracticeNo benefit found
Studies looked for a benefit and did not find one.
The one study found no benefit. Strongest study: a randomized controlled trial.
Human studies have not demonstrated improved oxygen utilization from Hot Yoga.
Open the Hot Yoga page

Show all 22

Comparing practices

CardioGood evidence it helps6 trials
CyclingGood evidence it helpsSize of effect: Small6 trials
High-Intensity Interval Training (HIIT)Some evidence it helpsSize of effect: Small4 trials

The expert view shows every study, dose protocol and source.

What may help

Linked to improving it22 listed

Start here

Highest probability, strongest evidence

PracticesCardioCertaintyHighSourceMeta-analysis6 other sources
A pooled analysis whose designs were not recorded found that aerobic exercise increased peak VO₂ by 2.14 in postoperative patients with coronary heart disease (95% CI (1.34, 2.94), p < 0.00001). A separate pooled analysis reported a large effect on relative VO₂max, though the population and number of participants for that result were not stated.
Who was studied
Healthy people and patients
Study result
aerobic exercise had a positive effect on Peak VO_2 in postoperative CHD patients (MD = 2.14, 95% CI (1.34, 2.94), p < 0.00001, I^2 = 36%)
Open Cardio
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PracticesCyclingCertaintyHighSourceRCTSmall effect6 other sources
Pooled analyses whose designs were not recorded found a small improvement in VO2peak with HIIT (SMD = 0.26 mL·kg⁻¹·min⁻¹, 95% CI: 0.08 to 0.44, P = 0.007). A separate pooled analysis found a small increase in maximal oxygen consumption with e-cycling, involving 78 people in its outcome analysis.
How big is the effect
Small effectA small but noticeable difference on average.
Who was studied
Healthy people and patients
Study result
The pooled analysis demonstrated that HIIT significantly improved VO2peak compared to control conditions (SMD = 0.26 mL·kg⁻¹·min⁻¹, 95% CI: 0.08 to 0.44, P = 0.007).
Open Cycling
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Medium probability(7)

PracticesHigh-Intensity Interval Training (HIIT)CertaintyMediumSourceRCTSmall effect7 other sources
A pooled analysis of randomized trials involving 713 people found an increase in peak heart rate, with considerable heterogeneity. A review of randomized trials involving 261 people also reported a small improvement in peak VO₂.
How big is the effect
Small effectA small but noticeable difference on average.
Who was studied
Healthy people and patients
Coronary Artery Disease
Diabetes Type1
Diabetes Type2
Obesity
Recent Heart Attack
Stroke
Study result
The pooled results showed that HIIT led to a statistically significant increase in Hrpeak (MD=5.51 bpm; 95% CI, 2.13 to 8.89), but the heterogeneity was considerable (I2=40%)
Open High-Intensity Interval Training (HIIT)
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PracticesBreathworkCertaintyMediumSourceRCT8 other sources
In a 2022 randomized trial of 291 people, arterial oxygen pressure on postoperative day 5 was higher with breathing exercises than in the control group (106.4 vs. 83.00 mmHg). A separate 2025 trial found higher blood oxygen saturation on the first day in the cardiovascular surgery unit.
Who was studied
People with a condition
Covid 19
Cystic Fibrosis
Heart Disease
Tuberculosis
Study result
The mean PaO2 (mmHg) of the ACBT group was significantly higher than that of the control group on POD 5 (106.4 vs. 83.00, p < 0.001)
Open Breathwork
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PracticesIce Bath / Cold PlungeCertaintyMediumSourceClinical5 other sources
An RCT involving 16 people found higher blood oxygen saturation with cold-water immersion than control at 10 min, 15 min, and 20 min. In another RCT involving 30 people, muscle oxygen consumption increased after training in the cold-water immersion group but not the active-control group.
Who was studied
Healthy people
Study result
SaO2 values were significantly higher in the CWI versus the CON group after 10 min (CWI 10 min: 97.94% ± 0.93% vs. CON 10 min: 96.69% ± 0.79%, p=.002), 15 min (97.75% vs 96.50%, p=.01), and 20 min (98.38% vs 96.81%, p<.001)
Open Ice Bath / Cold Plunge
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PracticesHot BathCertaintyMediumSourceClinical5 other sources
A trial of 21 healthy people found that water immersion increased the oxygen-uptake asymptote by +16%, +13% and +17%, depending on the measure, and increased area under the curve by +27%, +18% and +20%. Another trial found lower oxygen consumption during brief submaximal runs within 24 h after exercise with hot-water immersion at 41°.
Who was studied
Healthy people
Study result
HWI 41° reduced oxygen consumption rate during submaximal brief runs within 24 h postexercise (condition effect, p<0.05 as reported)
Open Hot Bath
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PracticesIndoor RowingCertaintyMediumSourceClinical4 other sources
In a 2023 randomized trial of 17 participants, relative VO2peak increased by 2.4 mL/kg/min from baseline at 6W and 12W. Another randomized trial found VO2peak increased from 18.06 ± 2.66 to 21.76 ± 3.22 mL·kg^-1·min^-1 after rowing training compared with the control group.
Who was studied
Healthy people and patients
Menopause
Study result
Relative VO2peak increased from baseline to 6W (P<0.001) and 12W (P<0.001; ∆2.4 mL/kg/min; 95% CI 0.9–3.9 mL/kg/min; g=2.03) in UBROW
Open Indoor Rowing
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PracticesSwimmingCertaintyMediumSourceClinical3 other sources
A randomized trial of 36 people found fitness test levels improved after exercise. A separate randomized trial of 21 reported that SmO2 decreased at T400 (5.5%, p = 0.017), so the reported findings do not point to a single direction of change in oxygen use.
Study result
All groups showed significantly better fitness test levels following the physical exercise intervention (p < 0.01)
Open Swimming
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PracticesTabata TrainingCertaintyMediumSourceClinical2 other sources
In a 2023 randomized trial of 48 people with overweight, VO2max was greater after 8 weeks in every group except the placebo group; O2 pulse also increased. In a separate 2014 trial, VO2 was 33.1±1.5 v. 27.2±1.6 ml/kg/min in the TAB condition (14 participants).
Who was studied
Healthy people and patients
Overweight
Study result
A significant main effect for time was noted for VO2max (P<0.001, Fig. 4A), SpO2 (P<0.04, Fig. 4B) and O2 pulse (P<0.002, Fig. 4C). In all groups except the control group (Pla), VO2max was greater at 8 weeks compared to baseline. Likewise, O2 pulse.
Open Tabata Training
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Low probability(11)

PracticesTai ChiCertaintyLowSourceRCTModerate effect1 other source
Pooled analyses whose designs were not recorded found higher maximal oxygen consumption (VO2 max) in an analysis of 171 people (SMD = 0.57, 95% CI (0.12, 1.03), p = 0.01), with a moderate effect.
How big is the effect
Moderate effectA clear difference on average.
Who was studied
People with a condition
Study result
maximal oxygen consumption (VO2 max) [SMD = 0.57, 95% CI (0.12, 1.03), p = 0.01]
Open Tai Chi
→
PracticesTENS / EMS TherapyCertaintyLowSourceRCT1 other source
Pooled analyses whose designs were not recorded found improved LSAT with TENS compared with control (MD = 5.95, 95% CI: 0.70–11.20; 488 people in this outcome’s analysis) in people with sleep apnea.
Who was studied
People with a condition
Sleep Apnea
Study result
TENS significantly improved LSAT compared to the control group (MD = 5.95, 95% CI: 0.70–11.20)
Open TENS / EMS Therapy
→
PracticesFoam RollingCertaintyLowSourceClinical2 other sources
In a trial of 25 participants, muscle oxygen saturation increased after exercise by 9.5%, 12%, and 8.8% in the reported stretching-and-rolling and stretching conditions. The finding was not specific to foam rolling, because an increase was also reported with static stretching alone.
Who was studied
People with a condition
Study result
Immediately after ECC, BF SmO2 tended to decrease non-significantly (p > 0.05), but increased significantly by 9.5% (p = 0.01, d = 0.57), 12% (p < 0.001, d = 0.89), and 8.8% (p = 0.011, d = 0.57) for DS+FR, SS+FR, and SS, respectively.
Open Foam Rolling
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PracticesDanceCertaintyLowSourceClinical1 other source
An RCT involving 50 people found a significant interaction between time and group for VO_2max (F(1, 35) = 4.326; p = 0.045, partial η^2 = 0.110). The control group’s cardiorespiratory fitness, measured by VO_2max, decreased from pre-test to post-test (F(1, 14) = 9.448, p = 0.008); the reported finding does not give the corresponding change for the dance group.
Who was studied
People with a condition
Study result
There was a statistically significant interaction between time and group for VO_2max: F(1, 35) = 4.326; p = 0.045, partial η^2 = 0.110. Regarding the control group, cardiorespiratory fitness, operationalized by VO_2max, decreased from pre-test to post-test (F(1, 14) = 9.448, p = 0.008, partial η^2 =
Open Dance
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PracticesRed Light Therapy (Photobiomodulation)CertaintyLowSourceClinical1 other source
A trial involving 32 women with obesity found that VO2 increased by 7% after photobiomodulation compared with before treatment.
Who was studied
People with a condition
Study result
VO2 increased in women with obesity post-PBM compared to pre-PBM (+7%, p < 0.001)
Open Red Light Therapy (Photobiomodulation)
→
PracticesPilatesCertaintyLowSourceClinical1 other source
A 2023 trial of 30 participants
Who was studied
People with a condition
Ankylosing Spondylitis
Study result
higher ratio between oxygen uptake and maximum heart rate (VO2/HRmax) by 14.83% (p = 0.04)
Open Pilates
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PracticesFastingCertaintyLowSourceClinical1 other source
In a randomized controlled trial of 16 people with overweight, a 3-week alternate-day fasting regimen reduced blood pressure and MVO2 and improved MFR.
Who was studied
People with a condition
Overweight
Study result
A 3-week ADF regimen reduced blood pressure and MVO2, and improved MFR.
Open Fasting
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PracticesFinnish SaunaCertaintyLowSourceClinical1 other source
In a quasi-experimental study of 15 people with heart failure, peak respiratory oxygen uptake increased from 13.3 +/- 1.8 to 16.3 +/- 2.1 mL/kg/min.
Who was studied
People with a condition
Heart Failure
Study result
increased peak respiratory oxygen uptake (13.3 +/- 1.8 to 16.3 +/- 2.1 mL/kg/min)
Open Finnish Sauna
→
PracticesCoherent BreathingCertaintyLowSourceAnecdotal1 other source
This effect was mentioned in 2 of 223 Reddit reports discussing it.
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PracticesPursed-Lip BreathingCertaintyLowSourceTheoretical1 other source
The proposed explanation is that Pursed-Lip Breathing prolongs exhalation, reduces air trapping, and improves ventilation-perfusion matching, which may support oxygen saturation and ease breathlessness during exertion. This is a rationale rather than a finding from human studies.
Study result
Pursed-lip breathing prolongs exhalation, reduces air trapping, and improves ventilation-perfusion matching, leading to better oxygen saturation and reduced dyspnea during exertion.
Open Pursed-Lip Breathing
→
PracticesLatin Dance FitnessCertaintyLowSourceTheoretical1 other source
Dance fitness is described as improving VO2max and oxygen extraction at the muscle level.
Study result
Dance fitness improves VO2max and oxygen extraction at the muscle level.
Open Latin Dance Fitness
→

Very low probability(2)

PracticesStrength TrainingCertaintyVery lowSourceRCTSmall effect1 other source
The studies did not support an improvement in oxygen utilization: a pooled analysis whose study designs were not recorded found VO2max improvements that did not reach statistical significance (SMD = 0.30, 95% CI: −0.19 to 0.79, p = 0.10) among 203 people in its analysis.
How big is the effect
Small effectA small but noticeable difference on average.
Who was studied
Healthy people
Open Strength Training
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PracticesHot YogaCertaintyVery lowSourceClinical1 other source
Human studies have not demonstrated improved oxygen utilization from Hot Yoga.
Who was studied
People with a condition
Open Hot Yoga
→

Practices compared

Practices with at least one trial of their own for this goal. Ranked by how sure the evidence is, then effect size.Top 10 of 17

Practice	How sure	Effect size	Own trials	What worked in trials
Cycling	CertaintyHighSourceRCT	Small effect	6 trials or pooled analyses	17–29 min · 2–3×/week · 4–10 weeks
Cardio	CertaintyHighSourceMeta-analysis		6 trials or pooled analyses	40–41 min · 1.1–3×/week · 6–30 weeks
High-Intensity Interval Training (HIIT)	CertaintyMediumSourceRCT	Small effect	4 trials or pooled analyses	3×/week · 8 weeks
Breathwork	CertaintyMediumSourceRCT		6 trials or pooled analyses	7×/week · 0.4–0.7 weeks
Hot Bath	CertaintyMediumSourceClinical		3 trials or pooled analyses
Ice Bath / Cold Plunge	CertaintyMediumSourceClinical		3 trials or pooled analyses	10 min
Indoor Rowing	CertaintyMediumSourceClinical		3 trials or pooled analyses	30 min · 3×/week · 2–10 weeks
Swimming	CertaintyMediumSourceClinical		3 trials or pooled analyses	2×/week · 3–6 weeks
Tabata Training	CertaintyMediumSourceClinical		2 trials or pooled analyses	4–12 min
Tai Chi	CertaintyLowSourceRCT	Moderate effect	1 trial or pooled analysis

What worked in trials: From the smallest to the typical amount in the trials that found this benefit. Not the most anyone did, not a target and not a limit.

How to read the evidence

Evidence tier — overall strength of the evidence for the whole compound

StrongWell established — backed by strong, consistent human research.
ModerateSome genuine support, but mostly from small or lower-quality studies. Promising, not proven.
PreliminaryEarly-stage evidence — a promising hypothesis, not an established effect yet.
LimitedVery limited evidence — treat this as a hypothesis, not proof.
InsufficientNot enough good evidence to draw conclusions yet.

Certainty — how sure we can be that the effect is real

Very highVery sure — strong, consistent evidence
HighFairly sure — consistent evidence from good studies
MediumModerately sure — new studies could change this
LowNot sure — little or mixed evidence
Very lowVery unsure — almost no usable evidence

Source — where the data comes from

Meta-analysisPooled analysis of many trials — the strongest evidence
RCTRandomized controlled trial — a strong human study design
ClinicalA human clinical study
Reference knowledgeFrom general health-science or pharmacology references, not a study of this exact claim
Animal researchStudied in animals, not humans
Community reportsAggregated user reports — anecdotal signal, not evidence
TheoreticalMechanism-based reasoning, not yet tested

Study grade — quality of each underlying study (A best, D weakest)

AHigh-quality — strong, consistent human trials
BGood — solid evidence with some limitations
CModerate — limited, small, or mixed-quality studies
DWeak — preliminary, indirect, or animal-only

Confidence — how strongly the sources back a finding

A 0–100 score from study quality and agreement

Most supplement evidence is graded C–D. Read it as preliminary signal, not proof.

Full write-up

What is it

Oxygen Utilization Improvement refers to better oxygen use during physical activity, typically reflected by changes in VO2 or VO2max measurements. In practical terms, it concerns the body’s capacity during exercise rather than a general feeling of wellbeing or simply breathing more. This effect has been studied in connection with activities and interventions such as Cycling, Hatha Yoga, Panax Ginseng, and Swimming.

How interventions help

Interventions linked with improved oxygen utilization fall into two broad groups: training-based approaches and supplements. Cycling, swimming, Hatha Yoga, and Tai Chi work through repeated physical practice, with findings generally focused on changes in VO2 or VO2max. These results should be interpreted in context, because the studies included healthy people, mixed populations, and people with clinical conditions rather than one uniform group.

Supplement studies used a wide range of schedules. Some findings followed short courses, such as 14 days for Panax Ginseng, 7 days for Spirulina, or 3-4 days for Omega-3, while others involved 4 weeks or longer. Beetroot Extract was studied after an acute single dose through approximately 15 days; reported changes appeared within days and could persist for days after stopping, and daily use was not required in the available study descriptions. These differences mean that a result seen after one exercise session or a short supplement course should not automatically be treated as a lasting adaptation.

The measured changes also differed. Some interventions were associated with higher VO2max, while others were associated with lower oxygen use at a matched exercise intensity, improved exercise economy, or changes in oxygen-related measurements. Iron had conflicting evidence, and Omega-3 findings were mixed across studies and did not include human evidence. Saccharomyces Boulardii was studied only in animals, so its finding does not establish that the same effect occurs in people. Overall, the evidence applies most directly to the populations and timeframes studied, not necessarily to every person or every form of oxygen-utilization difficulty.

Choosing guidance

The options differ substantially in how they are used. Cycling, Hatha Yoga, and Swimming are activity-based choices, making them most relevant for readers seeking an exercise or movement approach rather than a supplement. Hatha Yoga was studied in healthy participants, while Cycling included mixed health statuses; the populations studied for Swimming were not specified. Tai Chi may be more relevant to people with clinical conditions, although its evidence comes from a narrower study context than the activity options studied in healthy or mixed groups.

Among supplements, the time commitment varies. Panax Ginseng was studied at 500 mg/day for 14 days, Citrulline at 10 g/day for 4 weeks, Spirulina at 6 g/day for 7 days, Astaxanthin at 7 mg/day for 4 weeks, Chlorella at 6000 mg/day for 4 weeks, and L-Carnitine at 3 g/day for 2 months. Beetroot Extract is different: studies used an acute single dose to approximately 15 days, with effects categorized as appearing over days and persisting for days after stopping. These details may help distinguish a short-term trial from an approach requiring sustained daily use.

The human evidence is not equally direct across all options. Most listed interventions have human findings, but Saccharomyces Boulardii is supported by animal studies rather than human evidence. Ozone Therapy is described through a pharmacology reference rather than a human trial result, so it should not be compared directly with the exercise and supplement studies. Iron is also less straightforward because studies reported conflicting findings, while Omega-3 had mixed results across individual studies. These options may warrant more caution when choosing based on consistency rather than the direction of the reported effect.