9. Fatigue Cause No. 10: Dehydration
Your fatigue can be a sign of dehydration. Whether you’re working out or working a desk job, your body needs water to work well and keep cool. If you’re thirsty, you’re already dehydrated.
10. Fatigue Cause No. 11: Heart Disease
When fatigue strikes during everyday activities, such as cleaning the house or weeding the yard, it can be a sign that your heart is no longer up to the job. If you notice it’s becoming increasingly difficult to finish tasks that were once easy, talk to your doctor about heart disease.