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10 Reasons You're Always Tired That Have Nothing to Do With Sleep

Lack of sleep isn't the only reason you're constantly feeling fatigued.

You already know that getting enough sleep each night is essential for overall health. Snoozing for the recommended six to eight hours every evening keeps you energized for the day and helps you lose weight. But even if you go to bed early, get your full eight hours, and wake up at a reasonable time, you could still spend your day feeling constantly tired and lethargic.

There are a variety of reasons you're always tired. It could be chronic fatigue, a complicated disorder in which you feel weak and tired all the time and experience muscle and joint pain. But before your doctor delivers a chronic fatigue diagnosis, he or she must rule out a number of other medical disorders. Here are some of the biggest medical and lifestyle reasons you might be tired all the time. And to boost your energy, be sure to avoid the 40 Habits that Make You Sick and Fat.

You Have Anemia


If you find yourself frequently tired throughout the day, there's a chance you might have anemia. Anemia is a blood disorder that occurs when there aren't enough healthy red blood cells to carry oxygen from your lungs to your cells and tissues. Although some forms of anemia are hereditary, the most common form is iron-deficiency anemia, which can occur when someone doesn't eat enough iron in his or her diet.

The biggest symptom is fatigue, along with headaches, weakness, and dizziness. If these sound familiar, be sure to visit a doctor for a proper blood test and diagnosis. Fortunately, iron-deficiency anemia is easily treated with iron supplements and diet changes. Check out our list of The Best Iron Rich Foods to find out what to stock your kitchen with.

You're Depressed


Depression, which affects 350 million people worldwide, is a mental illness that's linked to a number of genetic and environmental factors, including a family history of mental illness, poor diet, and lack of exercise. Although overwhelming sadness lasting longer than two weeks is a major symptom of depression, this mental disorder also affects people physically. People who are depressed have increased fatigue, aches, and trouble sleeping. If you notice any of these symptoms, visit your doctor or a psychiatrist for a proper diagnosis.

You're Not Exercising


If you're tired all the time, it might seem counterproductive to hit the gym. After all, a tough workout can seriously wipe you out. But working out can also give you more lasting, all-day energy—exercise stimulates your cells to produce new mitochondria. This increases overall energy at the cellular level.

In fact, a study published in the journal Psychotherapy and Psychosomatics found that sedentary adults who performed low and moderate exercise for six weeks feel less fatigued. Something as simple as a walk around the neighborhood for 30 minutes can stimulate energy. So lace up your walking shoes and get some regular physical activity to reap all the health benefits.

You Have Diabetes


It's estimated that up to one-third of adults in the U.S. with diabetes are undiagnosed, so it's possible to live with this potentially fatal disease and not even know it. People with type 2 diabetes don't use glucose properly, leading to sugar building up in the blood instead of being used for energy.

Chronic tiredness is one of the first indicators that someone might have diabetes, along with being thirsty all the time, hunger, and frequent urination. Visit your doctor to get your blood sugar levels tested with a fasting plasma glucose test or an oral glucose tolerance test.

You Have an Underactive Thyroid


Your thyroid, the butterfly-shaped gland in your neck, secretes two major hormones that control major bodily functions and organs. From regulating body temperature to managing the heart and brain, your thyroid plays a big role in maintaining good health. So when your thyroid doesn't work properly, it throws your hormones out of whack. This could be one of the many reasons you're always tired.

If you have an underactive thyroid, also known as hypothyroidism, it means your body isn't getting enough thyroid hormones, and your cells don't get that "get going" signal, which leads to sluggishness. Chronic fatigue is one of the 10 Signs You Have an Underactive Thyroid, along with weight gain, high cholesterol, and a lower sex drive. Be sure to visit your doctor to get your thyroid checked with a simple blood test.

You're Not Eating Enough Calories


Although losing weight requires a careful balance of eating healthy, exercising, and getting plenty of sleep, it starts with cutting calories. After all, if you burn more calories than you take in, you'll inevitably lose weight. But it's possible to go overboard; your body needs calories for energy to function. One of the telltale signs of not eating enough calories is feeling tired all the time. Jim White, RD, ACSM, and owner of Jim White Nutrition Studios says you should never drop below 1,200 calories a day. For people who lead more active lifestyles, that number should be closer to 1,500-1,800 a day. Not only will cutting calories leave you feeling sluggish, but it will also slow down your metabolism and sabotage your weight-loss efforts.

You Eat Too Much Sugar


It's true your body needs glucose for energy, but too much sugar can interfere with your energy levels. If you eat a sugary meal or snack (think: flavored yogurt, blueberry muffin, or sweetened granola), it spikes your blood sugar, leading to an inevitable crash and feelings of sluggishness later. Do this enough and your body will be constantly recovering from each sugary binge. And it's not just cookies and donuts that can send your blood sugar over the edge—be sure to avoid the 14 'Health' Foods Worse Than a Donut.

You're Not Drinking Enough Water


If you find yourself constantly tired and reaching for yet another coffee or soda for a pick-me-up, stop. Your body might actually need more replenishing water than caffeine to stay alert. "I find dehydration can quickly sap a person of energy and have us reaching for food and often caffeinated beverages," Liz Bloom, RD, says. Instead, pour yourself a glass of water and be sure you're drinking at least 64 ounces a day. Bloom recommends reaching for detox water to keep you sipping all day long. "Choosing foods such as citrus, frozen berries, cucumbers and fresh herbs can add a burst of flavor to water and release some of the nutritional benefits within those foods while providing hydration and therefore sustained energy," she adds.

You're Not Eating Enough Carbs


Drastically cutting carbs is a common fad diet people turn to when they're looking to lose weight quickly. After all, each gram of carb holds on to about one gram of water, so when people cut carbs they also lose water weight and think they're losing fat. However, carbs are essential for energy. White says one of the biggest mistakes he sees people make when trying to lose weight is they eliminate carbs and therefore have no energy to make it through the day, let alone hit the gym.

But not all carbs are created equal. You should be getting your carbohydrates from complex sources, such as whole grains, vegetables, and fruit. Even if you're trying to lose weight, White recommends carbs still make up 45-65 percent of your daily calorie intake. That's somewhere between 100 and 200 grams, depending on your caloric needs. Otherwise, you could find yourself feeling tired, sluggish, and irritable.

You Need More Vitamin D


Slathering on sunblock and protecting your skin from the sun is great to ward off skin cancer and wrinkles, but you shouldn't shun the sunshine entirely. Fatigue is one of the biggest symptoms of a vitamin D deficiency, and many adults don't get enough of the sunshine vitamin. But if you live in a cloudy climate or just want to protect your skin from those harmful UVA and UVB rays, you can still take a vitamin D supplement or eat more of the 5 Best Foods for Body-Boosting Vitamin D.