Potential Causes of Afternoon Tiredness

A metabolic disorder could be the cause

tired woman with her eyes closed at her desk

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Anyone who is overworked or not getting enough sleep at night can feel tired towards the end of the day. Add the daily stresses of family, kids, commuting, and work and it is not surprising that some days we just feel exhausted and ready for bed long before it is time. In mild cases of an afternoon slump, a good nights' sleep and eating healthier foods can usually resolve the symptoms, but not all afternoon slump symptoms are so easily addressed. For a growing percentage of those who suffer from this, extreme fatigue could be a warning sign of a serious metabolic disorder.

Severe symptoms include a profound and intense desire to sleep, muscle fatigue, sweating, the shakes, headaches, changes in vision, or any combination of these symptoms. These symptoms are not signs of "normal" sluggishness but are often signs of pre-diabetes, type 2 diabetes, or insulin resistance.

Sitting Disease

As more employees have become sedentary, the number of desk workers who develop "Sitting Disease" is on the rise. Sitting disease is a disorder that puts workers at an increased risk of pre-diabetes, type 2 diabetes, and for cardiovascular problems.

Experts reported that even people who sit for extended periods but regularly hit the gym are at risk. Exercise in itself, though obviously critical to our bodies overall, doesn't seem to counter the damaging effects of all this time spent seated.

There are many reasons people develop a sluggish feeling in the afternoon (and for some, the "afternoon" slump occurs in mid-morning). When symptoms worsen or become severe enough that they decrease your ability to complete tasks, you may want to seek advice from a physician to rule out certain health problems.


Pre-diabetes is a condition in ​which your body begins to suffer from changes in how it metabolizes carbohydrates. There are few early warning signs, so it is best to see a doctor if you are having severe afternoon slump symptoms or have other risk factors associated with pre-diabetes.

Insulin Resistance and Metabolic Syndrome (formerly called Syndrome X) are similar to pre-diabetes in that they are metabolic disorders that affect how the body metabolizes carbohydrates.

Pre-diabetes, insulin resistance, and metabolic syndrome can all be early warnings signs of type 2 diabetes. Type 2 diabetes is diagnosed when blood sugar levels are no longer in a normal or "pre-diabetic" range.

Insulin Resistance

Insulin is a hormone made by the pancreas. It acts as a key to open cells in the body and blood cells to allow energy (glucose) to enter in. Without insulin, a person would die because the energy from the food they eat would not be able to be used by the body. When blood sugar builds up in the bloodstream, it can damage all organs and tissues in the body and brain and cause coma and death if not treated.

If you have insulin resistance, your body may need to overproduce insulin to keep your blood sugars within a normal range, or, it may not make enough insulin to keep your blood sugars in balance. It is called insulin resistance because your body resists the normal action of insulin.

Overproduction of insulin can cause fluctuations in blood sugar, weight gain, moodiness, changes in your menstrual cycle (for women), excess facial hair (women), skin tags, changes in skin color (dark, velvety patches called acanthosis nigricans), and periods of profound fatigue.

Insulin resistance is more common in people who also have severe allergies, thyroid disorders (especially Hashimoto's Thyroiditis), women who have polycystic ovarian syndrome and can be caused by certain types of medications.