Best Natural And Healthy Ways Of Fighting Fatigue 5.00/5 (100.00%) 4 votes Often, due to various causes, too many toxins enter our body or remain on skin. These cause lethargy, inactivity and fatigue. Decrease in energy levels can be caused by malnutrition, high sugar and carbohydrate intake, too much sex, insomnia, obesity and hormonal imbalance. [...]