5 min|Dr. Jam Caleda

3 Dietary Factors That Cause Unexplained Fatigue

Wellness, Nutrition

As a doctor, a common complaint that we see in our offices is fatigue. This insidious symptom is an emergent property of many (if not most) pathology, as it slowly gels our life into stagnation and for some to debilitating lengths. In many cases, treating the underlying disorder results in the improvement of the symptom, however, in many instances the reason for fatigue can be difficult to diagnose, or altogether, unidentified. For these patients, conventional medicine has little to offer.

On the other hand, nutritional medicine frequently is beneficial to those with unexplained fatigue. Systematic reviews have shown that approximately 70-80% of these patients will experience significant improvements with nutritional interventions (1-3). In this blog, I’ll look at the most common dietary factors that I’ve seen been a component of unexplained fatigue.

Reactive Hypoglycemia

Reactive hypoglycemia is one of the most common factors that contribute to unexplained fatigue (4,5). This condition is characterized by the body’s reaction to a spike in blood sugar. When we consume glucose (sugar), it is absorbed in our gut into the blood stream, where our body uses insulin to stabilize the levels in our blood. Insulin does this by moving the glucose into our cells where it can be used for metabolism.

In a normal body, both insulin and blood sugar levels stay fairly stable, even after a high sugar meal.However in reactive hypoglycemia, which is the early stages of diabetes, this cycle becomes aberrant. In reactive hypoglycemia when we eat a high sugar meal, our blood sugar spikes very high. Subsequently our insulin levels spike as well, and they rush to reduce the blood sugar levels, so much so that they drop our blood sugar to amounts so low that we experience severe bouts of fatigue after the meal.

This process can precipitate over time until our blood sugar and insulin levels yoyo throughout the day even when we don’t eat high sugar meals. The result is an underlying symptom of fatigue.Things that precipitate reactive hypoglycemia include stress, anxiety, hormonal imbalances, and a lack of exercise.

In my experience a program that includes the avoidance of refined sugar and refined carbohydrates is paramount. This is supported through the consumption of small, frequent meals and supplements to help stabilize the blood sugar levels.

Food Sensitivities

Food allergies or sensitivities are another common cause of unexplained fatigue. Numerous studies have reported that food sensitivities impacts our energy both in children and adults (6-8). Allergic fatigue may be associated with other symptoms of allergy such as skin conditions, nasal congestion, abdominal pain, headaches, joint pain, and irritability to name a few.

These patients report that they actually feel better when they are fasting as opposed to after eating a meal. However many people who regularly ingested hidden food allergens may become addicted to that food, and in most cases are not aware that they are sensitive at all. This makes it challenging to determine the allergy.There are a few tests that we can use to help this diagnosis.

The first would be a blood spot test, where a sample of blood is cross-referenced with different common foods and analyzed for allergic markers. Here at Integrative, we can also use a Biomeridian Test, which accesses the meridian channels in the body to determine common food sensitivities. The gold standard for determining sensitivity is an elimination diet. This involves abstaining from most foods for a period of 3-6 weeks, then slowly reintroducing foods and determining which ones are causing the allergic symptoms.


Caffeine is a silent culprit. We especially don’t think of caffeine as being a cause for fatigue, especially because it’s something that perks us up. However in published case reports 6 patients with severe sleepiness experienced a significant improvement or resolution of sleepiness after they stopped consuming caffeine. Proposed mechanisms of how coffee can impact fatigue include interfering with sleep cycles and triggering reactive hypoglycemia.

These causes can be compounded of other organic disorders that can be the root of why someone experiences fatigue, but where many fall through the cracks that don’t have a disease that is causing their symptoms being aware of these three dietary factors can be the game changing part of a case. Research has shown that prescribed nutritional supplements such as potassium, iron, multivitamins, amino acids, and IV therapies can be helpful as well. In the end we utilize food as medicine.

  1. Werbach, Melvyn R. “Nutritional strategies for treating chronic fatigue syndrome.” Alternative Medicine Review2 (2000): 93-108.
  2. Chambers, Duncan, et al. “Interventions for the treatment, management and rehabilitation of patients with chronic fatigue syndrome/myalgic encephalomyelitis: an updated systematic review.” Journal of the Royal Society of Medicine10 (2006): 506-520.
  3. Alraek, Terje, et al. “Complementary and alternative medicine for patients with chronic fatigue syndrome: a systematic review.” BMC complementary and alternative medicine1 (2011): 1.
  4. Karlan, Samuel C., and Clarence Cohn. “Hypoglycemic fatigue.” Journal of the American Medical Association9 (1946): 553-555.
  5. Portis, Sidney A. “Life situations, emotions and hyperinsulinism.” Journal of the American Medical Association16 (1950): 1281-1286.
  6. Rowe, A. H. “Allergic fatigue and toxemia.” Annals of allergy1 (1959): 9.
  7. Speer, Frederic. “The allergic tension-fatigue syndrome in children.” International Archives of Allergy and Immunology3-4 (1958): 207-214.
  8. Randolph, Theron G. “Allergy as a causative factor of fatigue, irritability, and behavior problems of children.” The Journal of pediatrics5 (1947): 560-572.
  9. Roehrs, Timothy, and Thomas Roth. “Caffeine: sleep and daytime sleepiness.” Sleep medicine reviews2 (2008): 153-162.
  10. Regestein, Quentin R. “Pathologic sleepiness induced by caffeine.” The American journal of medicine5 (1989): 586-588.
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