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The relationship between nutrition and fatigue

By The Health News Team | March 1, 2023
Man eating chips on couch while watching tv

You’ve heard the expression, “You are what you eat.” Well, it’s also important to note that what you eat affects how you feel.

According to Dr. Darius Schneider, a Sharp Community Medical Group board-certified endocrinologist, one of the first signals of poor nutrition is fatigue. “Some foods can cause or worsen fatigue and even lead to mood disturbances and depression,” he says.

These fatigue-causing and mood-altering foods include fast carbohydrates, saturated fats and foods with nitrates. However, other foods, such as berries, green leafy vegetables, nuts, seeds and fermented foods combined with plenty of hydration, can improve mood and wellbeing.

What is fatigue?

Fatigue is a feeling of constant tiredness or weakness and can be physical, mental or a combination of both. Although fatigue is sometimes described as tiredness, it is different than simply feeling tired or sleepy. Everyone feels tired at some point, but this is usually resolved with a nap or a few nights of good sleep — and for some, exercise.

“Fatigue is a symptom, not a condition,” Dr. Schneider says. “For many people, fatigue is caused by a combination of lifestyle, social, psychological and general wellbeing issues rather than an underlying medical condition.”

Symptoms of fatigue can include:

  • Chronic tiredness or sleepiness

  • Headache

  • Dizziness

  • Sore or aching muscles

  • Slowed reflexes and responses

  • Impaired decision-making and judgment

  • Moodiness and irritability

  • Appetite loss or increase

  • Reduced immune system function

  • Blurry vision

  • Short-term memory problems

  • Poor concentration and attentiveness

  • Hallucinations

  • Low motivation

What causes fatigue?

Along with emotional concerns, stress and medical causes, such as thyroid disorder, heart disease or diabetes, fatigue can be caused by lifestyle factors. These include poor sleep quality, alcohol or drug use, lack of regular exercise, and importantly, poor nutrition.

“High-energy or high-calorie foods that are nutritionally poor don’t provide the body with enough fuel or nutrients to function at its best,” Dr. Schneider says. “Quick-fix foods, such as hastily eaten protein bars or caffeinated drinks, only offer a temporary energy boost that quickly wears off and worsens fatigue.”

According to Dr. Schneider, over the last 75 years, we have moved from a primarily whole-foods diet to one that is based on processed foods and refined plants. The main features of the modern American diet, he laments, consist of lots of meat, processed food, added fat and sugar, and not enough fruits, vegetables and whole grains.

“We are experiencing a ‘chronic fatigue’ and ‘bad mood’ epidemic — we may be 100 times more likely to have significant mood problems than people born 100 years ago,” Dr. Schneider says. “Mood and fatigue are the first casualties of poor nutrition long before our physical health begins to deteriorate.”

What helps prevent fatigue?

To energize your brain and body with good nutrition, Dr. Schneider quotes Michael Pollan, an author, journalist and professor of science and environmental journalism, in advising, “Eat food. Not too much. Mostly plants.” Pollan also recommends not eating “anything your grandmother wouldn’t recognize as food.”

Dr. Schneider’s additional tips for “energized eating” include:

  • Plan your meals and don’t grocery shop when hungry.

  • Have healthy snacks at hand, such as nuts, berries, dark chocolate with no less than 60% cocoa, edamame, celery sticks, avocados and apples.

  • Replace fried foods with grilled or baked foods and white foods, such as potatoes and rice, with green or colorful foods, such as leafy greens, fruits and vegetables.

  • Limit caffeine and alcohol use.

  • Limit high-calorie foods packed with nitrates, such as sausage and processed cheese.

  • Read nutrition labels and question ingredients.

  • Avoid mindless eating — it rarely involves healthy choices.

  • Avoid sugary drinks and drink water instead.

“Ask yourself how your diet impacts your energy and mood,” Dr. Schneider says. “What are the foods that positively impact your mood and energy levels and vice versa? And move whenever and wherever you can — anything but sitting.”

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Dr. Darius Schneider

Dr. Darius Schneider


Dr. Darius Schneider is a board-certified endocrinologist affiliated with Sharp Community Medical Group.

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