---
title: "Observational Studies | Mike Sinn"
description: "Observational analyses of real-world health data. Correlation, handled cautiously."
url: https://mikesinn.com/observational-studies
---

# Observational studies

Discover cause-and-effect relationships from real-world data. See how different factors influence health outcomes based on millions of observations.

15.8K cause-effect relationships

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Showing 15,837 studies

[Nervousness — Overall Mood — Higher Nervousness Predicts Very Slightly Lower Overall Mood for Population — 471 participants — 11.3K data pairs — r = -0.19 — -4.7% effect — Very low strength — Low confidence — Emotions — Emotions](https://studies.dfda.earth/study/cause-1388-effect-1398-population-study/) [Overall Mood — Jitteriness — Higher Overall Mood Predicts Very Slightly Lower Jitteriness for Population — 359 participants — 8.4K data pairs — r = -0.14 — -4.2% effect — Very low strength — Low confidence — Emotions — Emotions](https://studies.dfda.earth/study/cause-1398-effect-1361-population-study/) [Interest — Overall Mood — Higher Interest Predicts Slightly Higher Overall Mood for Population — 353 participants — 6.6K data pairs — r = 0.33 — +14.2% effect — Low strength — Low confidence — Emotions — Emotions](https://studies.dfda.earth/study/cause-1356-effect-1398-population-study/) [Overall Mood — Interest — Higher Overall Mood Predicts Slightly Higher Interest for Population — 338 participants — 6.8K data pairs — r = 0.36 — +27.2% effect — Low strength — Low confidence — Emotions — Emotions](https://studies.dfda.earth/study/cause-1398-effect-1356-population-study/) [Resilience — Overall Mood — Higher Resilience Predicts Slightly Higher Overall Mood for Population — 336 participants — 6.9K data pairs — r = 0.32 — +13.3% effect — Low strength — Low confidence — Emotions — Emotions](https://studies.dfda.earth/study/cause-1436-effect-1398-population-study/) [Pride — Overall Mood — Higher Pride Predicts Slightly Higher Overall Mood for Population — 323 participants — 6.6K data pairs — r = 0.29 — +12.8% effect — Low strength — Low confidence — Emotions — Emotions](https://studies.dfda.earth/study/cause-1411-effect-1398-population-study/) [Overall Mood — Resilience — Higher Overall Mood Predicts Slightly Higher Resilience for Population — 314 participants — 6.9K data pairs — r = 0.36 — +24.2% effect — Low strength — Low confidence — Emotions — Emotions](https://studies.dfda.earth/study/cause-1398-effect-1436-population-study/) [Overall Mood — Pride — Higher Overall Mood Predicts Slightly Higher Pride for Population — 303 participants — 6.8K data pairs — r = 0.34 — +32.4% effect — Low strength — Low confidence — Emotions — Emotions](https://studies.dfda.earth/study/cause-1398-effect-1411-population-study/) [Outdoor Humidity — Overall Mood — Higher Outdoor Humidity Predicts Very Slightly Lower Overall Mood for Population — 275 participants — 141 data pairs — r = -0.00 — +3.1% effect — Very low strength — Medium confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954744-effect-1398-population-study/) [Barometric Pressure — Overall Mood — Higher Barometric Pressure Predicts Very Slightly Lower Overall Mood for Population — 274 participants — 170 data pairs — r = -0.01 — +2.9% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-96380-effect-1398-population-study/) [Outdoor Temperature — Overall Mood — Higher Outdoor Temperature Predicts Very Slightly Lower Overall Mood for Population — 257 participants — 27.5K data pairs — r = -0.04 — -0.3% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954773-effect-1398-population-study/) [Precipitation — Overall Mood — Higher Precipitation Predicts Very Slightly Lower Overall Mood for Population — 246 participants — 271 data pairs — r = -0.01 — +4.1% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954746-effect-1398-population-study/) [Cloud Cover Amount — Overall Mood — Higher Cloud Cover Amount Predicts Very Slightly Higher Overall Mood for Population — 181 participants — 20.8K data pairs — r = 0.01 — +0.5% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954747-effect-1398-population-study/) [Calories Burned — Sleep Duration — Higher Calories Burned Predicts Slightly Higher Sleep Duration for Population — 180 participants — 350 data pairs — r = 0.20 — +272.4% effect — Low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-1280-effect-1867-population-study/) [Walk Or Run Distance — Sleep Duration — Higher Walk Or Run Distance Predicts Very Slightly Higher Sleep Duration for Population — 157 participants — 41.4K data pairs — r = 0.08 — +14.5% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-1304-effect-1867-population-study/) [Calories Burned — Body Mass Index Or BMI — Higher Calories Burned Predicts Very Slightly Higher Body Mass Index Or BMI for Population — 149 participants — 416 data pairs — r = 0.02 — +0.7% effect — Very low strength — High confidence — Physical Activity — Physique](https://studies.dfda.earth/study/cause-1280-effect-1272-population-study/) [Calories Burned — Awakenings — Higher Calories Burned Predicts Very Slightly Higher Awakenings for Population — 148 participants — 325 data pairs — r = 0.10 — +101.6% effect — Very low strength — High confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-1280-effect-1906-population-study/) [Daily Step Count — Sleep Duration — Higher Daily Step Count Predicts Very Slightly Higher Sleep Duration for Population — 147 participants — 39.9K data pairs — r = 0.05 — +25.4% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-1451-effect-1867-population-study/) [Walk Or Run Distance — Awakenings — Higher Walk Or Run Distance Predicts Very Slightly Higher Awakenings for Population — 139 participants — 48.6K data pairs — r = 0.10 — +642.9% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-1304-effect-1906-population-study/) [Daily Step Count — Awakenings — Higher Daily Step Count Predicts Very Slightly Higher Awakenings for Population — 139 participants — 48.3K data pairs — r = 0.10 — +295.4% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-1451-effect-1906-population-study/) [Calories Burned — Sleep Start Time — Higher Calories Burned Predicts Very Slightly Lower Sleep Start Time for Population — 137 participants — 541 data pairs — r = -0.08 — -5.0% effect — Very low strength — High confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-1280-effect-5211821-population-study/) [Daily Step Count — Body Mass Index Or BMI — Higher Daily Step Count Predicts Very Slightly Higher Body Mass Index Or BMI for Population — 134 participants — 51.9K data pairs — r = 0.01 — +0.6% effect — Very low strength — Low confidence — Physical Activity — Physique](https://studies.dfda.earth/study/cause-1451-effect-1272-population-study/) [Walk Or Run Distance — Body Mass Index Or BMI — Higher Walk Or Run Distance Predicts Very Slightly Lower Body Mass Index Or BMI for Population — 133 participants — 53.0K data pairs — r = -0.00 — +0.0% effect — Very low strength — Low confidence — Physical Activity — Physique](https://studies.dfda.earth/study/cause-1304-effect-1272-population-study/) [Body Weight — Sleep Duration — Higher Body Weight Predicts Very Slightly Higher Sleep Duration for Population — 131 participants — 39.0K data pairs — r = 0.03 — +105.8% effect — Very low strength — Low confidence — Physique — Sleep](https://studies.dfda.earth/study/cause-1486-effect-1867-population-study/) [Walk Or Run Distance — Sleep Start Time — Higher Walk Or Run Distance Predicts Very Slightly Lower Sleep Start Time for Population — 126 participants — 54.2K data pairs — r = -0.03 — -0.4% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-1304-effect-5211821-population-study/) [Daily Step Count — Sleep Start Time — Higher Daily Step Count Predicts Very Slightly Lower Sleep Start Time for Population — 123 participants — 50.8K data pairs — r = -0.04 — -0.5% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-1451-effect-5211821-population-study/) [Body Weight — Awakenings — Higher Body Weight Predicts Very Slightly Lower Awakenings for Population — 123 participants — 35.7K data pairs — r = -0.02 — +25.8% effect — Very low strength — Low confidence — Physique — Sleep](https://studies.dfda.earth/study/cause-1486-effect-1906-population-study/) [Barometric Pressure — Calories Burned — Higher Barometric Pressure Predicts Very Slightly Lower Calories Burned for Population — 120 participants — 246 data pairs — r = -0.03 — +0.0% effect — Very low strength — Low confidence — Environment — Physical Activity](https://studies.dfda.earth/study/cause-96380-effect-1280-population-study/) [Walk Or Run Distance — Sleep Efficiency — Higher Walk Or Run Distance Predicts Very Slightly Lower Sleep Efficiency for Population — 119 participants — 28.1K data pairs — r = -0.02 — -0.5% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-1304-effect-5211811-population-study/) [Daily Step Count — Sleep Efficiency — Higher Daily Step Count Predicts Very Slightly Lower Sleep Efficiency for Population — 119 participants — 26.5K data pairs — r = -0.02 — -0.5% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-1451-effect-5211811-population-study/) [Precipitation — Calories Burned — Higher Precipitation Predicts Very Slightly Lower Calories Burned for Population — 118 participants — 263 data pairs — r = -0.01 — +0.0% effect — Very low strength — Low confidence — Environment — Physical Activity](https://studies.dfda.earth/study/cause-5954746-effect-1280-population-study/) [Awakenings — Body Mass Index Or BMI — Higher Awakenings Predicts Very Slightly Lower Body Mass Index Or BMI for Population — 117 participants — 30.0K data pairs — r = -0.01 — -0.0% effect — Very low strength — Low confidence — Sleep — Physique](https://studies.dfda.earth/study/cause-1906-effect-1272-population-study/) [Body Mass Index Or BMI — Awakenings — Higher Body Mass Index Or BMI Predicts Very Slightly Lower Awakenings for Population — 116 participants — 34.1K data pairs — r = -0.01 — +43.2% effect — Very low strength — Low confidence — Physique — Sleep](https://studies.dfda.earth/study/cause-1272-effect-1906-population-study/) [Body Mass Index Or BMI — Sleep Duration — Higher Body Mass Index Or BMI Predicts Very Slightly Higher Sleep Duration for Population — 114 participants — 36.2K data pairs — r = 0.02 — +107.7% effect — Very low strength — Low confidence — Physique — Sleep](https://studies.dfda.earth/study/cause-1272-effect-1867-population-study/) [Cloud Cover — Overall Mood — Higher Cloud Cover Predicts Very Slightly Lower Overall Mood for Population — 113 participants — 9.5K data pairs — r = -0.03 — -0.2% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5957090-effect-1398-population-study/) [Sleep Duration — Body Mass Index Or BMI — Higher Sleep Duration Predicts Very Slightly Higher Body Mass Index Or BMI for Population — 113 participants — 33.3K data pairs — r = 0.01 — -0.1% effect — Very low strength — Low confidence — Sleep — Physique](https://studies.dfda.earth/study/cause-1867-effect-1272-population-study/) [Outdoor Temperature — Irritability — Higher Outdoor Temperature Predicts Very Slightly Lower Irritability for Population — 112 participants — 234 data pairs — r = -0.02 — +2.4% effect — Very low strength — High confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954773-effect-1358-population-study/) [Barometric Pressure — Irritability — Higher Barometric Pressure Predicts Very Slightly Higher Irritability for Population — 112 participants — 6.9K data pairs — r = 0.01 — +4.4% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-96380-effect-1358-population-study/) [Outdoor Humidity — Irritability — Higher Outdoor Humidity Predicts Very Slightly Higher Irritability for Population — 111 participants — 6.9K data pairs — r = 0.03 — -0.1% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954744-effect-1358-population-study/) [Water (mL) — Body Weight — Higher Water (mL) Predicts Very Slightly Lower Body Weight for Population — 109 participants — 381 data pairs — r = -0.08 — +0.0% effect — Very low strength — Low confidence — Foods — Physique](https://studies.dfda.earth/study/cause-109592-effect-1486-population-study/) [Body Weight — Sleep Start Time — Higher Body Weight Predicts Very Slightly Higher Sleep Start Time for Population — 109 participants — 54.7K data pairs — r = 0.01 — -0.4% effect — Very low strength — Low confidence — Physique — Sleep](https://studies.dfda.earth/study/cause-1486-effect-5211821-population-study/) [Outdoor Temperature — Sleep Duration — Higher Outdoor Temperature Predicts Very Slightly Higher Sleep Duration for Population — 107 participants — 377 data pairs — r = 0.03 — -11.2% effect — Very low strength — Medium confidence — Environment — Sleep](https://studies.dfda.earth/study/cause-5954773-effect-1867-population-study/) [Outdoor Temperature — Walk Or Run Distance — Higher Outdoor Temperature Predicts Very Slightly Higher Walk Or Run Distance for Population — 107 participants — 219 data pairs — r = 0.09 — +0.0% effect — Very low strength — Low confidence — Environment — Physical Activity](https://studies.dfda.earth/study/cause-5954773-effect-1304-population-study/) [Sleep Duration — Overall Mood — Higher Sleep Duration Predicts Very Slightly Lower Overall Mood for Population — 105 participants — 8.5K data pairs — r = -0.00 — +2.6% effect — Very low strength — Low confidence — Sleep — Emotions](https://studies.dfda.earth/study/cause-1867-effect-1398-population-study/) [Outdoor Humidity — Sleep Duration — Higher Outdoor Humidity Predicts Very Slightly Lower Sleep Duration for Population — 105 participants — 23.8K data pairs — r = -0.01 — +1.1% effect — Very low strength — Low confidence — Environment — Sleep](https://studies.dfda.earth/study/cause-5954744-effect-1867-population-study/) [Barometric Pressure — Walk Or Run Distance — Higher Barometric Pressure Predicts Very Slightly Lower Walk Or Run Distance for Population — 105 participants — 221 data pairs — r = -0.04 — +0.0% effect — Very low strength — Low confidence — Environment — Physical Activity](https://studies.dfda.earth/study/cause-96380-effect-1304-population-study/) [Barometric Pressure — Sleep Duration — Higher Barometric Pressure Predicts Very Slightly Higher Sleep Duration for Population — 105 participants — 23.3K data pairs — r = 0.01 — +1.4% effect — Very low strength — Low confidence — Environment — Sleep](https://studies.dfda.earth/study/cause-96380-effect-1867-population-study/) [Body Weight — Sleep Efficiency — Higher Body Weight Predicts Very Slightly Higher Sleep Efficiency for Population — 103 participants — 21.8K data pairs — r = 0.05 — -0.1% effect — Very low strength — Low confidence — Physique — Sleep](https://studies.dfda.earth/study/cause-1486-effect-5211811-population-study/) [Body Mass Index Or BMI — Sleep Start Time — Higher Body Mass Index Or BMI Predicts Very Slightly Lower Sleep Start Time for Population — 103 participants — 55.0K data pairs — r = -0.00 — -0.4% effect — Very low strength — Low confidence — Physique — Sleep](https://studies.dfda.earth/study/cause-1272-effect-5211821-population-study/) [Sleep Start Time — Body Mass Index Or BMI — Higher Sleep Start Time Predicts Very Slightly Lower Body Mass Index Or BMI for Population — 102 participants — 54.8K data pairs — r = -0.01 — +0.1% effect — Very low strength — Low confidence — Sleep — Physique](https://studies.dfda.earth/study/cause-5211821-effect-1272-population-study/) [Overall Mood — Sleep Duration — Higher Overall Mood Predicts Very Slightly Lower Sleep Duration for Population — 101 participants — 7.9K data pairs — r = -0.02 — -6.6% effect — Very low strength — Low confidence — Emotions — Sleep](https://studies.dfda.earth/study/cause-1398-effect-1867-population-study/) [Calories Burned — Resting Heart Rate (Pulse) — Higher Calories Burned Predicts Very Slightly Lower Resting Heart Rate (Pulse) for Population — 99 participants — 377 data pairs — r = -0.04 — -1.8% effect — Very low strength — Medium confidence — Physical Activity — Vital Signs](https://studies.dfda.earth/study/cause-1280-effect-5211891-population-study/) [Precipitation — Irritability — Higher Precipitation Predicts Very Slightly Lower Irritability for Population — 99 participants — 6.6K data pairs — r = -0.00 — -1.6% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954746-effect-1358-population-study/) [Water (mL) — Body Mass Index Or BMI — Higher Water (mL) Predicts Very Slightly Lower Body Mass Index Or BMI for Population — 97 participants — 51.8K data pairs — r = -0.08 — +0.4% effect — Very low strength — Low confidence — Foods — Physique](https://studies.dfda.earth/study/cause-109592-effect-1272-population-study/) [Body Mass Index Or BMI — Sleep Efficiency — Higher Body Mass Index Or BMI Predicts Very Slightly Higher Sleep Efficiency for Population — 97 participants — 18.2K data pairs — r = 0.04 — -0.4% effect — Very low strength — Low confidence — Physique — Sleep](https://studies.dfda.earth/study/cause-1272-effect-5211811-population-study/) [Sleep Efficiency — Body Mass Index Or BMI — Higher Sleep Efficiency Predicts Very Slightly Higher Body Mass Index Or BMI for Population — 96 participants — 15.2K data pairs — r = 0.01 — +0.3% effect — Very low strength — Low confidence — Sleep — Physique](https://studies.dfda.earth/study/cause-5211811-effect-1272-population-study/) [Precipitation — Sleep Duration — Higher Precipitation Predicts Very Slightly Lower Sleep Duration for Population — 96 participants — 23.1K data pairs — r = -0.01 — +1.5% effect — Very low strength — Low confidence — Environment — Sleep](https://studies.dfda.earth/study/cause-5954746-effect-1867-population-study/) [Fat Burn Heart Rate Zone Minutes — Resting Heart Rate (Pulse) — Higher Fat Burn Heart Rate Zone Minutes Predicts Slightly Higher Resting Heart Rate (Pulse) for Population — 95 participants — 26.5K data pairs — r = 0.32 — +3.3% effect — Low strength — Low confidence — Physical Activity — Vital Signs](https://studies.dfda.earth/study/cause-5211861-effect-5211891-population-study/) [Outdoor Humidity — Nervousness — Higher Outdoor Humidity Predicts Very Slightly Higher Nervousness for Population — 95 participants — 5.9K data pairs — r = 0.04 — -0.1% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954744-effect-1388-population-study/) [Fat Burn Heart Rate Zone Calories Out — Resting Heart Rate (Pulse) — Higher Fat Burn Heart Rate Zone Calories Out Predicts Very Slightly Higher Resting Heart Rate (Pulse) for Population — 94 participants — 26.1K data pairs — r = 0.19 — +2.3% effect — Very low strength — Low confidence — Physical Activity — Vital Signs](https://studies.dfda.earth/study/cause-5211851-effect-5211891-population-study/) [Barometric Pressure — Nervousness — Higher Barometric Pressure Predicts Very Slightly Higher Nervousness for Population — 94 participants — 5.8K data pairs — r = 0.06 — +6.0% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-96380-effect-1388-population-study/) [Fat Burn Heart Rate Zone Minutes — Sleep Start Time — Higher Fat Burn Heart Rate Zone Minutes Predicts Very Slightly Lower Sleep Start Time for Population — 94 participants — 36.1K data pairs — r = -0.03 — +0.4% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-5211861-effect-5211821-population-study/) [Tiredness / Fatigue — Overall Mood — Higher Tiredness / Fatigue Predicts Slightly Lower Overall Mood for Population — 93 participants — 3.6K data pairs — r = -0.25 — -9.4% effect — Low strength — Low confidence — Symptoms — Emotions](https://studies.dfda.earth/study/cause-87760-effect-1398-population-study/) [Walk Or Run Distance — Resting Heart Rate (Pulse) — Higher Walk Or Run Distance Predicts Very Slightly Lower Resting Heart Rate (Pulse) for Population — 93 participants — 26.0K data pairs — r = -0.04 — -0.5% effect — Very low strength — Low confidence — Physical Activity — Vital Signs](https://studies.dfda.earth/study/cause-1304-effect-5211891-population-study/) [Cardio Heart Rate Zone Minutes — Resting Heart Rate (Pulse) — Higher Cardio Heart Rate Zone Minutes Predicts Very Slightly Higher Resting Heart Rate (Pulse) for Population — 93 participants — 26.4K data pairs — r = 0.08 — +0.9% effect — Very low strength — Low confidence — Physical Activity — Vital Signs](https://studies.dfda.earth/study/cause-5211881-effect-5211891-population-study/) [Cardio Heart Rate Zone Minutes — Sleep Start Time — Higher Cardio Heart Rate Zone Minutes Predicts Very Slightly Lower Sleep Start Time for Population — 93 participants — 37.5K data pairs — r = -0.05 — -0.7% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-5211881-effect-5211821-population-study/) [Fat Burn Heart Rate Zone Calories Out — Sleep Start Time — Higher Fat Burn Heart Rate Zone Calories Out Predicts Very Slightly Lower Sleep Start Time for Population — 93 participants — 24.5K data pairs — r = -0.00 — -0.2% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-5211851-effect-5211821-population-study/) [Daily Step Count — Resting Heart Rate (Pulse) — Higher Daily Step Count Predicts Very Slightly Lower Resting Heart Rate (Pulse) for Population — 92 participants — 24.1K data pairs — r = -0.05 — -0.6% effect — Very low strength — Low confidence — Physical Activity — Vital Signs](https://studies.dfda.earth/study/cause-1451-effect-5211891-population-study/) [Outdoor Temperature — Nervousness — Higher Outdoor Temperature Predicts Very Slightly Lower Nervousness for Population — 92 participants — 5.5K data pairs — r = -0.09 — -2.0% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954773-effect-1388-population-study/) [Outdoor Humidity — Alertness — Higher Outdoor Humidity Predicts Very Slightly Higher Alertness for Population — 92 participants — 4.4K data pairs — r = 0.07 — +1.6% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954744-effect-1258-population-study/) [Water (mL) — Sleep Start Time — Higher Water (mL) Predicts Very Slightly Lower Sleep Start Time for Population — 92 participants — 78.6K data pairs — r = -0.07 — -0.8% effect — Very low strength — Low confidence — Foods — Sleep](https://studies.dfda.earth/study/cause-109592-effect-5211821-population-study/) [Barometric Pressure — Alertness — Higher Barometric Pressure Predicts Very Slightly Lower Alertness for Population — 92 participants — 4.4K data pairs — r = -0.01 — +0.9% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-96380-effect-1258-population-study/) [Outdoor Temperature — Alertness — Higher Outdoor Temperature Predicts Very Slightly Lower Alertness for Population — 91 participants — 4.3K data pairs — r = -0.01 — -0.4% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954773-effect-1258-population-study/) [Sleep Start Time — Resting Heart Rate (Pulse) — Higher Sleep Start Time Predicts Very Slightly Higher Resting Heart Rate (Pulse) for Population — 90 participants — 22.9K data pairs — r = 0.04 — +0.6% effect — Very low strength — Low confidence — Sleep — Vital Signs](https://studies.dfda.earth/study/cause-5211821-effect-5211891-population-study/) [Resting Heart Rate (Pulse) — Sleep Start Time — Higher Resting Heart Rate (Pulse) Predicts Very Slightly Higher Sleep Start Time for Population — 90 participants — 22.9K data pairs — r = 0.04 — +0.9% effect — Very low strength — Low confidence — Vital Signs — Sleep](https://studies.dfda.earth/study/cause-5211891-effect-5211821-population-study/) [Barometric Pressure — Guiltiness — Higher Barometric Pressure Predicts Very Slightly Higher Guiltiness for Population — 89 participants — 6.2K data pairs — r = 0.07 — +4.4% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-96380-effect-1335-population-study/) [Outdoor Humidity — Guiltiness — Higher Outdoor Humidity Predicts Very Slightly Higher Guiltiness for Population — 89 participants — 6.2K data pairs — r = 0.04 — +5.0% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954744-effect-1335-population-study/) [Fat Burn Heart Rate Zone Minutes — Sleep Efficiency — Higher Fat Burn Heart Rate Zone Minutes Predicts Very Slightly Lower Sleep Efficiency for Population — 88 participants — 14.7K data pairs — r = -0.07 — -0.9% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-5211861-effect-5211811-population-study/) [Fat Burn Heart Rate Zone Calories Out — Sleep Efficiency — Higher Fat Burn Heart Rate Zone Calories Out Predicts Very Slightly Lower Sleep Efficiency for Population — 88 participants — 13.7K data pairs — r = -0.03 — -0.2% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-5211851-effect-5211811-population-study/) [Cardio Heart Rate Zone Calories Out — Resting Heart Rate (Pulse) — Higher Cardio Heart Rate Zone Calories Out Predicts Very Slightly Lower Resting Heart Rate (Pulse) for Population — 88 participants — 15.2K data pairs — r = -0.01 — -0.1% effect — Very low strength — Low confidence — Physical Activity — Vital Signs](https://studies.dfda.earth/study/cause-5211871-effect-5211891-population-study/) [Facebook Posts — Overall Mood — Higher Facebook Posts Predicts Very Slightly Higher Overall Mood for Population — 88 participants — 6.6K data pairs — r = 0.00 — -1.0% effect — Very low strength — Low confidence — Social Interactions — Emotions](https://studies.dfda.earth/study/cause-1884-effect-1398-population-study/) [Outdoor Humidity — Enthusiasm — Higher Outdoor Humidity Predicts Very Slightly Lower Enthusiasm for Population — 87 participants — 4.3K data pairs — r = -0.05 — +0.1% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954744-effect-1307-population-study/) [Caloric Intake — Sleep Duration — Higher Caloric Intake Predicts Very Slightly Higher Sleep Duration for Population — 87 participants — 8.8K data pairs — r = 0.07 — +6.9% effect — Very low strength — Low confidence — Nutrients — Sleep](https://studies.dfda.earth/study/cause-1283-effect-1867-population-study/) [Barometric Pressure — Enthusiasm — Higher Barometric Pressure Predicts Very Slightly Higher Enthusiasm for Population — 87 participants — 82 data pairs — r = 0.02 — -2.9% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-96380-effect-1307-population-study/) [Water (mL) — Awakenings — Higher Water (mL) Predicts Very Slightly Higher Awakenings for Population — 87 participants — 28.6K data pairs — r = 0.05 — +28.8% effect — Very low strength — Low confidence — Foods — Sleep](https://studies.dfda.earth/study/cause-109592-effect-1906-population-study/) [Cardio Heart Rate Zone Minutes — Awakenings — Higher Cardio Heart Rate Zone Minutes Predicts Very Slightly Higher Awakenings for Population — 87 participants — 22.3K data pairs — r = 0.04 — +48.6% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-5211881-effect-1906-population-study/) [Fat Burn Heart Rate Zone Minutes — Awakenings — Higher Fat Burn Heart Rate Zone Minutes Predicts Very Slightly Higher Awakenings for Population — 87 participants — 22.4K data pairs — r = 0.04 — +110.8% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-5211861-effect-1906-population-study/) [Cardio Heart Rate Zone Minutes — Sleep Efficiency — Higher Cardio Heart Rate Zone Minutes Predicts Very Slightly Lower Sleep Efficiency for Population — 87 participants — 14.7K data pairs — r = -0.04 — -0.8% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-5211881-effect-5211811-population-study/) [Outdoor Humidity — Distress — Higher Outdoor Humidity Predicts Very Slightly Higher Distress for Population — 87 participants — 90 data pairs — r = 0.01 — +6.1% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954744-effect-1305-population-study/) [Cardio Heart Rate Zone Calories Out — Sleep Start Time — Higher Cardio Heart Rate Zone Calories Out Predicts Very Slightly Lower Sleep Start Time for Population — 87 participants — 137 data pairs — r = -0.01 — +0.0% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-5211871-effect-5211821-population-study/) [Precipitation — Nervousness — Higher Precipitation Predicts Very Slightly Lower Nervousness for Population — 87 participants — 5.7K data pairs — r = -0.00 — +0.1% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954746-effect-1388-population-study/) [Outdoor Temperature — Guiltiness — Higher Outdoor Temperature Predicts Very Slightly Lower Guiltiness for Population — 86 participants — 5.6K data pairs — r = -0.04 — +0.6% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954773-effect-1335-population-study/) [Daily Step Count — Overall Mood — Higher Daily Step Count Predicts Very Slightly Higher Overall Mood for Population — 86 participants — 140 data pairs — r = 0.04 — +3.9% effect — Very low strength — Low confidence — Physical Activity — Emotions](https://studies.dfda.earth/study/cause-1451-effect-1398-population-study/) [Outdoor Temperature — Distress — Higher Outdoor Temperature Predicts Very Slightly Higher Distress for Population — 86 participants — 115 data pairs — r = 0.01 — -5.7% effect — Very low strength — Medium confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954773-effect-1305-population-study/) [Overall Mood — Tiredness / Fatigue — Higher Overall Mood Predicts Slightly Lower Tiredness / Fatigue for Population — 86 participants — 3.5K data pairs — r = -0.25 — -12.0% effect — Low strength — Low confidence — Emotions — Symptoms](https://studies.dfda.earth/study/cause-1398-effect-87760-population-study/) [Water (mL) — Sleep Duration — Higher Water (mL) Predicts Very Slightly Higher Sleep Duration for Population — 86 participants — 33.6K data pairs — r = 0.20 — +180.6% effect — Very low strength — Low confidence — Foods — Sleep](https://studies.dfda.earth/study/cause-109592-effect-1867-population-study/) [Water (mL) — Walk Or Run Distance — Higher Water (mL) Predicts Very Slightly Higher Walk Or Run Distance for Population — 86 participants — 362 data pairs — r = 0.09 — +0.0% effect — Very low strength — Low confidence — Foods — Physical Activity](https://studies.dfda.earth/study/cause-109592-effect-1304-population-study/) [Outdoor Temperature — Enthusiasm — Higher Outdoor Temperature Predicts Very Slightly Higher Enthusiasm for Population — 86 participants — 4.1K data pairs — r = 0.02 — +2.6% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-5954773-effect-1307-population-study/) [Barometric Pressure — Distress — Higher Barometric Pressure Predicts Very Slightly Higher Distress for Population — 86 participants — 4.1K data pairs — r = 0.02 — +8.6% effect — Very low strength — Low confidence — Environment — Emotions](https://studies.dfda.earth/study/cause-96380-effect-1305-population-study/) [Fat Burn Heart Rate Zone Calories Out — Awakenings — Higher Fat Burn Heart Rate Zone Calories Out Predicts Very Slightly Lower Awakenings for Population — 86 participants — 17.7K data pairs — r = -0.03 — +10.4% effect — Very low strength — Low confidence — Physical Activity — Sleep](https://studies.dfda.earth/study/cause-5211851-effect-1906-population-study/) 

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