Do you often ask yourself, "Why am I so tired all the time?" If so, this article compiles a list of some of the most common reasons for tiredness and what you can do to bounce back into action.

According to the Centers for Disease Control and Prevention (CDC), around 15.3% of women and 10.1% of men regularly feel very tired or exhausted in the United States.

Tiredness can cause an array of problems. For example, around 1 in 25 adult drivers report falling asleep at the wheel each month.

About 72,000 crashes and 44,000 injuries each year are a result of drowsy driving, and that's not to mention the estimated 6,000 fatal crashes caused by drowsy drivers.

Everyone feels tired at some point in their lives—whether it's due to a late night out, staying up to watch your favorite TV show, or putting in some extra hours at work.

Often, you can put your finger on the reason you're not feeling your best, but what about those times when you can't pinpoint the cause of your tiredness? What makes you feel tired then?

Here are some possible explanations for why you could be feeling so drained and the steps that you can take to feel re-energized.

1. Lack of sleep

A lack of sleep may seem an obvious reason for feeling tired, yet 1 in 3 US adults are consistently not getting enough of it.

People aged between 18 and 60 years need 7 or more hours of sleep every day to promote optimal health, according to The American Academy of Sleep Medicine and the Sleep Research Society.

Getting under the recommended hours of sleep each night is not only associated with fatigue, impaired performance, and a greater risk of accidents, but it also has adverse health outcomes.

These include obesity, high blood pressure, depression, heart disease, stroke, and an increased risk of death.

If you struggle to fit in 7 hours of sleep, here are some tips to help you achieve a full dose of much-needed slumber:

• Maintain a consistent sleep routine. Try to go to bed at the same time every night and get up at the same time each morning—even on the weekends.

• Avoid naps. We need a certain amount of sleep within a 24-hour period and no more than that. Napping reduces the amount of sleep that we require the following night, which might lead to difficulty getting to sleep and fragmented sleep.

• Limit time awake in bed to 5–10 minutes. If you find that you are lying awake in bed worrying or with your mind racing, get out of bed and sit in the dark until you are feeling sleepy, then go back to bed.

• Ensure that your bedroom is quiet, dark, and a comfortable temperature. Any light that enters your room could disturb your sleep. Ensure that your room is dark and that light emitted from digital devices is out of sight. Cooler room temperatures are considered better to promote sleep than warmer temperatures.

• Limit caffeinated drinks. Try not to consume caffeinated beverages after noon. The stimulating effects of caffeine can last for many hours after intake and cause issues with initiating sleep.

• Avoid tobacco and alcohol before bed. Smoking cigarettes and drinking alcohol before going to bed may cause fragmented sleep.

If you practice all the sleeping habits listed above and still wake up tired, it might be a good idea to contact your health-care provider and discuss whether you have a sleep-related medical problem such as insomnia, obstructive sleep apnea, or restless legs syndrome.

2. Poor diet

The easiest way to banish tiredness is to make adjustments to your diet. Eating a healthful and balanced diet can make the world of difference to how you feel.

To improve your health and get all the nutrients you need—as well as eliminate fatigue—it is vital to choose a healthful mix of food from the five food groups, which are: fruits, vegetables, grains, protein, and dairy.

You can switch up your eating style today by implementing some of these small changes:

• Eat the right amount of calories for your sex, age, weight, and activity level. Eating either too much or too little can make you feel sluggish.
• Fill half of your plate with fruits and vegetables. Be sure to focus on eating whole fruits and a selection of vegetables.
• Ensure whole grains make up half the grains you consume. Examples of whole grains include brown rice, oatmeal, whole cornmeal, bulgur, and whole-wheat flour.
• Shift to low-fat and fat-free dairy to help limit your calories from saturated fats.
• Vary your protein routine. Try to choose lean poultry and meat, limit processed meats, choose unsalted nuts and seeds, and select some omega-3-rich seafood.
• Cut down on sugar. Sugar can give you a quick rush of energy, but it wears off fast and might make you feel more tired. Avoid foods and drinks that have lots of added sugar.
• Never skip breakfast. Regularly skipping breakfast can lead to you missing out on key nutrients and the energy that you need to kick-start your day.
• Eat at regular intervals. Sustain your energy levels by eating three meals per day and limiting unhealthful snacks.
• Drink enough water. Drinking water can help to prevent dehydration, which results in fatigue, unclear thinking, mood changes, overheating, and constipation.

3. Sedentary lifestyle

When tiredness sets in, sitting on the couch and relaxing could seem to be the only answer. But getting up and moving may be the best thing you can do to re-energize and eradicate fatigue.

Research by the University of Georgia (UGA) in Athens discovered that compared with sitting quietly, one single bout of moderate-intensity exercise lasting for at least 20 minutes helped to boost energy.

An earlier study by UGA also found that when sedentary individuals completed an exercise program regularly, their fatigue improved compared with those who did not.

The US Department of Health and Human Services Physical Activity Guidelines for Americans suggest that all adults need 2 hours and 30 minutes of moderate-intensity exercise per week and muscle-strengthening activities that work all the major muscle groups on 2 or more days per week.

This may seem to be a lot of time spent exercising, but you can spread out your activity across the week and, in total, it is just the amount of time that you might otherwise spend watching a movie.

If you have not exercised for a while, start slowly. Begin with a brisk 10-minute walk each day and build up to walking fast for 30 minutes on 5 days per week.

Brisk walking, water aerobics, riding a bike, playing tennis, and even pushing a lawnmower can all count toward your time spent doing moderate-intensity exercise.

4. Excessive stress

Many situations can cause stress. Work, financial problems, relationship issues, major life events, and upheavals such as moving house, unemployment, and bereavement—the list of potential stressors is never-ending.

A little stress can be healthy and may actually make us more alert and able to perform better in tasks such as interviews, but stress is only a positive thing if it is short-lived.

Excessive, prolonged stress can cause physical and emotional exhaustion and lead to illness.

Stress makes your body generate more of the "fight-or-flight" chemicals that are designed to prepare your body for an emergency.

In situations such as an office environment where you can't run away or fight, the chemicals that your body has produced to protect you can't be used up and, over time, can damage your health.

If the pressures that you face are making you feel overtired or giving you headaches, migraines, or tense muscles, don't ignore these signals. Take some time out until you feel calmer, or try some of these tips.

• Identify the source of stress. Until you can recognize what is causing you to create and maintain stress, you will be unable to control your stress levels.
• Keep a stress journal to identify patterns and common themes.
• Learn to say no. Never take on too much—be aware of your limits and stick to them.
• Avoid those who stress you out. If there is someone in your life causing you a significant amount of stress, try to spend less time in their company.
• Communicate your concerns. Learn to express your feelings and concerns instead of keeping them bottled up if something is bothering you.
• View situations in a different way. Try to look at stressful situations in a more positive light. For example, if you're stuck in a traffic jam, see it as an opportunity to have some alone time and listen to your favorite tunes.
• Look at the bigger picture. Think about whether the stressful situation will matter in a month's time. Is it worth getting upset about?
• Accept the things you are unable to change. Some sources of stress, such as an illness or the death of a loved one, are unavoidable. Often, the best way to deal with stress is to try and accept things the way they are.
• Learn to forgive. We are all human and often make mistakes. Let go of anger, resentments, and negative energy by forgiving friends, family, and colleagues and moving on.

Physical activity is a significant stress reliever and releases feel-good endorphins. If you are feeling stress build up, go for a walk, take your dog out, or even put on some music and dance around the room.

5. Medical conditions

If you have made lifestyle changes to do with your physical activity, diet, stress levels, and sleep but still feel tired all the time, there could be an underlying medical condition.

Some of the most common conditions that report fatigue as a key symptom include:

• anemia
• underactive thyroid
• diabetes
• anxiety
• depression
• chronic fatigue syndrome
• urinary tract infection
• food intolerance
• heart disease
• glandular fever
• pregnancy
• vitamin and mineral deficiencies

If you are concerned that you have a medical condition that is causing you to feel tired, arrange an appointment with your health-care provider to discuss your worries as soon as possible.