Anyone can experience fatigue at any moment, although it usually manifests itself after strenuous physical activity, a demanding workday, or both. Exercise frequently results in fatigue, which can be reduced by getting enough rest, taking a good nap, or getting a full night's sleep. Contrarily, fatigue is a persistent, uncharacteristic state of tiredness and sleepiness. It might be difficult and demotivating to maintain your regular routine when you're tired. It may be chronic (lasting longer than a month) or acute (lasting more than a month or 1 to 6 months or longer).

One's short- and long-term levels of fatigue are directly related to the food they eat. For instance, iron deficiency is linked to fatigue, reduced work capacity, and subpar academic performance. Similar to empty calorie items, foods with added sugar and solid fats like sweets and soft drinks have little nutritional benefit. As a result, you might feel full even when you haven't eaten any of the nutrient-dense foods your body needs.