While most people can relate to feeling tired, fatigue is much more than that. Fatigue is a kind of unrelenting exhaustion that affects your ability to concentrate and feel motivated or energized. It develops over time and can’t be treated with rest.

The National Safety Council reports 38 percent of Americans, or more than 54 million people, describe themselves as sleep-deprived. This kind of weariness not only affects emotional and psychological health, it increases the risk of accidents behind the wheel and on the job. Moreover, between 836,000 and 2.5 million Americans have chronic fatigue syndrome, estimates the Centers for Disease Control and Prevention.

Understanding how lifestyle factors into fatigue can help. We spoke with two medical professionals who answered our questions about the causes and conditions behind fatigue as well as what you can do to find relief.

Here’s what they had to say.

Dr. Michael Lam

What is adrenal fatigue?

Adrenal fatigue is when your adrenal glands are unable to function properly and involves several debilitating symptoms. At the onset, it manifests itself gradually. Adult patients often report experiencing lethargy and fatigue. Aside from these, other symptoms include:

  • fearfulness
  • anxiety
  • depression
  • difficulty in concentrating
  • reduced memory
  • insomnia

Meanwhile, some people are unable to lose weight as a symptom of fatigue, while others report experiencing arthritis and influenza.

It’s also important to distinguish adrenal fatigue from Addison’s disease. Addison’s disease is a condition caused by adrenal glands that aren’t functioning. In contrast, stress primarily causes adrenal fatigue. For this reason, adrenal fatigue is a non-Addison’s form of adrenal dysfunction.

What’s the best way to combat adrenal fatigue?

Since chronic stress essentially causes adrenal fatigue, reducing your stress levels can help in overcoming this condition. Making healthy lifestyle changes also help, including altering your daily diet.

If you have a mild case of adrenal fatigue, making these changes alone may be enough to relieve the condition. If, however, they prove to be an insufficient remedy, you may want to consider taking certain nutritional supplements.

These include:

  • vitamin B-5
  • vitamin B-12
  • vitamin C
  • vitamin D
  • selenium
  • pregnenolone
  • cortisol
  • magnesium
  • pantethine
  • dehydroepiandrosterone (DHEA)
Before you take dietary supplementsBefore you attempt to treat your fatigue with dietary supplements, do your research or consult your doctor, pharmacist, or dietitian to determine whether it’s the best choice for you. Some supplements can interact with over-the-counter or prescribed medications.

What are some of the unusual symptoms of adrenal fatigue?

When it comes to adrenal fatigue, you may experience certain symptoms that are uncommon in other people. This is especially true for advanced cases.

They include:

  • sudden onset of anxiety attacks while resting
  • heart palpitations despite having a normal cardiac function
  • sudden feeling of lightheadedness or dizziness, even while at rest
  • sudden fluctuations in blood pressure
  • constipation despite adequate doses of magnesium and vitamin C

These symptoms indicate that the adrenal glands have already lost their ability to maintain the control needed for your body to retain a stable internal equilibrium. Trying to correct this without the help of a physician typically fails, because normal healing remedies can’t address symptoms effectively.

In this case, you should consult with a professional immediately, especially if you’re experiencing several uncommon symptoms.

Michael Lam, MD, MPH, ABAAM, is a physician specializing in nutritional and anti-aging medicine. Dr. Lam received his Bachelor of Science degree from Oregon State University and his Doctor of Medicine degree from the Loma Linda University School of Medicine in California. He also holds a master’s degree in public health. He’s board-certified by the American Board of Anti-Aging Medicine, where he’s also served as a board examiner.

Dr. Mike Dow

How does stress cause fatigue?

Getting stuck in the exhaustion phase of the stress response can lead to fatigue in a variety of ways. There are four subtypes of a “drained brain,” or how people respond to stressors (also referred to as general adaptation syndrome), which I lay out in my book, “Heal Your Drained Brain”:

  • Light drain. Adrenaline, norepinephrine, and cortisol levels increase slightly and stay that way. The result of this is minor stress.
  • Skyrocket drain. Much like “light drain,” all three stress hormones rise. The difference, however, is that the spike is quick and can leave the person with feelings of panic and dread.
  • Drop drain. The three stress hormones mentioned above begin to rise but then fall. This blunted response means you don’t have the energy to get through stressors, like a 5 p.m. deadline you might have just been handed.
  • X-treme drain. Adrenaline and norepinephrine increase but cortisol decreases. This makes you feel edgy and wired but too tired and fatigued to do anything about it.

The ultimate goal is that these stress hormones will rise and fall like a wave and allow you the energy to get through life’s stressors — and resist fatigue.

What’s the role between fatigue and the 24-hour cycle of melatonin and cortisol?

In the morning, cortisol should rise as melatonin levels fall. At night, the reverse should take place. The cortisol spike in the morning helps us wake up, and the melatonin spike at night helps us fall asleep.

This, however, can be thrown off balance by something as simple as using your phone. The blue light emitted from your phone can suppress the melatonin in your brain, while the stressful email your boss might have just sent you can spike your cortisol levels. Suddenly, your melatonin levels are now low and cortisol levels are high when they should be reversed.

How can foods help fight fatigue?

Foods that spike your blood sugar — think carbohydrates, fatty foods, alcohol — can shrink the brain’s hippocampus while also disrupting deep sleep. Meanwhile, foods high in omega-6s can lead to many conditions that cause fatigue.

In order to fight fatigue, you’ll want to eat foods that are high in omega-3s, like salmon and other types of fish, and low in sugar that give your brain the vitamin and mineral cofactors.

Dr. Mike Dow, PsyD, PhD, is a psychotherapist, neurotherapist, and the New York Times’ best-selling author of “The Brain Fog Fix” and “Healing the Broken Brain." His newest book is Chicken Soup for the Soul’s Think, Act & Be Happy. Throughout his career, he’s hosted several television series, served as a go-to expert in relationships, brain health, addiction, and mental illness, and can currently be heard weekly on Hay House Radio’s “The Dr. Mike Show.”

Jessica has been a writer and editor for over 10 years. Following the birth of her first son, she left her advertising job to begin freelancing. Today, she writes, edits, and consults for a great group of steady and growing clients as a work-at-home mom of four, squeezing in a side gig as a fitness co-director for a martial arts academy. Between her busy home life and mix of clients from varied industries — like stand-up paddleboarding, energy bars, industrial real estate, and more — Jessica never gets bored.