1. Food Intolerance
If you’ve noticed that you feel sleepy ten to 30 minutes after eating certain foods (postprandial somnolence), you may have an undiagnosed food allergy or intolerance to a specific type of food.

Food intolerances or sensitivities typically cause symptoms like rashes, digestive problems, runny nose or headaches.

Generally, it is caused by a lack of digestive enzymes in the stomach which prevent the food from being properly absorbed.

But fatigue is another symptom that’s often overlooked.

Also, research suggests that quality of life may be more affected by fatigue in those with food sensitivities (3).

Common food intolerances include gluten, dairy, eggs, soy, and corn.

If you suspect that certain foods may be making you tired, speak with your allergist or dietitian for possible solutions.

2. Sleeping at the Wrong Time
It’s self-evident that sleeping at the wrong time or lack of sleep and tiredness go hand in hand and can reduce your energy.

Sleeping during the day instead of at night disrupts your body’s circadian rhythm, which are the biological changes that occur in response to light and darkness during a 24-hour cycle.

Research has found that when your sleep pattern is out of sync with your circadian rhythm, chronic fatigue may develop (4).

This is a common problem among people who perform shift or night work.

Sleep experts estimate that 2–5% of all shift workers suffer from a sleep disorder characterized by excessive sleepiness or disrupted sleep over a period of one month or more (5).

What’s more, even staying awake during the night for a day or two can cause fatigue.

It’s best to sleep during the night whenever possible, respect the circadian rhythm.

However, if your job involves shift work, there are strategies to retrain your body clock, which should improve your energy levels.

Using glasses to block blue light may also help people who perform shift work.

3. Consuming too Many Refined Carbohydrate
Carbs can be a quick source of energy. When you eat them, your body breaks them down into sugar, which can be used for fuel.

However, eating too many refined carbs can actually cause you to feel tired throughout the day.

When sugar and processed carbs are consumed, they cause a rapid rise in your blood sugar. This signals your pancreas to produce a large amount of insulin to get the sugar out of your blood and into your cells.

This spike in blood sugar levels — and subsequent fall — can make you feel exhausted. Craving quick energy, you instinctively reach for another serving of refined carbs, which can lead to a vicious cycle.

Luckily, research suggests that some foods may help protect against tiredness (6, 7).

To keep your energy levels stable, replace sugar and refined carbs with whole foods that are rich in fiber.

4. Problems with your Thyroid
The thyroid gland which is found in the neck releases hormones that control how your body uses food for energy.

Hyperthyroidism occurs when your thyroid produces the hormone thyroxine in excess, while hypothyroidism develops when it produces too little.

Both conditions share the symptoms of fatigue and muscle weakness.

5. High-Stress Levels
Chronic stress may have a profound effect on your energy levels and quality of life.

Although some stress is normal, excessive levels of stress have been linked to fatigue in several studies (8, 9).

In addition, your response to stress can influence how tired you feel.

While you may not be able to avoid stressful situations, developing strategies for managing your stress may help prevent you from feeling completely exhausted.

For instance, large reviews of studies suggest yoga and meditation can help relieve stress (10, 11).

Engaging in these or similar mind-body practices may ultimately help you feel more energetic and better able to cope with stress.

6. Not Getting Quality Sleep
Not getting enough sleep is one of the more obvious causes of fatigue.

Your body does many things while you sleep, including store memory and release hormones that regulate your metabolism and energy levels (12).

After a night of high-quality sleep, you typically wake up feeling refreshed, alert and energized.

Importantly, sleep should be restful and uninterrupted in order to allow your brain to go through all five stages of each sleep cycle (13).

In addition to getting enough sleep, maintaining a regular sleep routine also seems to help prevent tiredness.

Just one week of sleep deprivation can change your genes (14). It can also cause brain deterioration, resulting in permanent memory loss and cognitive deficiencies (15).

And if that’s not frightening enough, lack of sleep has been shown to bring about depression, induce weight gain, and can even lead to a premature demise (16).

Furthermore, napping may help boost energy levels.

To improve the amount and quality of your sleep, go to bed at roughly the same time every night, relax before sleeping and get plenty of activity during the day.

However, if you find it difficult to fall or stay asleep and suspect you may have a sleeping disorder, speak to your doctor about having your sleep evaluated by a specialist.

7. Inadequate Hydration
Tiredness, irritability and poor concentration are signs that you may not be getting enough fluids.

Each day, water in the body is lost through insensibly through breathing, sweating, urination, and bowel movements and needs to be replaced with liquids from food and drink.

Staying well hydrated is important for maintaining good energy levels.

It is worthy of note that, biochemical reactions that take place in the body every day result in a loss of water that needs to be replaced.

Dehydration occurs when you don’t drink enough liquid to replace the water lost in your urine, stools, sweat and breath.

Several studies have shown that being even mildly dehydrated can lead to lower energy levels and a decreased ability to concentrate (17, 18).

Although you may have heard that you should drink eight, 8-ounce (237-ml) glasses of water daily, you may require more or less than this depending on your weight, age, gender and level of activity.

8. Living a Sedentary Lifestyle
Inactivity could be the root cause of your low energy. But many people say they’re too tired to exercise.

In one recent study, this was the most common reason that middle-aged and older adults gave for not exercising (19).

One explanation could be chronic fatigue syndrome (CFS), which is characterized by extreme, unexplained fatigue on a daily basis.

Research suggests people with CFS tend to have low strength and endurance levels, which limit their exercise ability (20, 21).

To boost your energy levels, replace sedentary behaviors with active ones.

9. Depression
It’s completely natural to feel sadness as a response to life’s struggles, but if feelings of listlessness, despair, or melancholy last for more than two weeks you may be suffering from depression.

Depression can range from mild to severe and often includes symptoms of low energy, slowed thinking, as well as sleeping too much or too little.

Fatigue and depression are deeply intertwined with either state fuelling the other.

One study observed that people who are depressed are four times more likely to feel fatigued, and people who suffer from fatigue are three times as likely to become depressed (22).

Depression tends to make people feel overwhelmed by even the most routine of tasks.

10. Anemia
Anemia is one of the top causes of feeling constantly run-down.

Causing fatigue, weakness, and poor concentration, anemia occurs when the body doesn’t have enough red blood cells to carry sufficient oxygen to tissues and organs in the body.

The most common kinds of anemia are caused by iron and vitamin deficiencies. To prevent anemia, your diet should include iron, folate, vitamin B12 and Vitamin C.

Source: http://www.currenthealthtips.com/reasons-why-are-always-tired-how-fix-it/

OP many thanks for this, its was quite educative

Nice post