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The Human Effect Matrix looks at human studies to tell you what supplements affect Lower Respiratory Tract Infection Risk.
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| Grade | Level of Evidence [show legend] |
|---|---|
|
Robust research conducted with repeated double-blind clinical trials |
|
Multiple studies where at least two are double-blind and placebo controlled |
|
Single double-blind study or multiple cohort studies |
|
Uncontrolled or observational studies only |
|
Level of Evidence
?
The amount of high quality evidence. The more
evidence, the more we can trust the results.
|
Supplement |
Magnitude of effect
?
The direction and size of the supplement's impact on
each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.
|
Consistency of research results
?
Scientific research does not always agree. HIGH or
VERY HIGH means that most of the scientific research agrees.
|
Notes |
|---|---|---|---|---|
|
|
- | Very High See all 4 studies |
Studies have not found a lower rate of lower respiratory tract infections. However, it's possible that those with low vitamin D levels could see some benefit. More evidence is needed.
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