Fatigue in Cancer Patients May be Related to Serotonin

Patients who are struggling with cancer often find the condition and treatment causes increased levels of fatigue. Fatigue is a very common symptom experienced by patients as their bodies struggle with tremendous changes within. The causes of fatigue are complex and are due to cellular alterations through to lifestyle and dietary changes. More recent research in Austria has found links between changes in inflammation, tryptophan and fatigue.

The study found a link in changes in tryptophan metabolism, which is a precurssor for serotonin. There was an alteration in the pathway favouring kynurenine instead of serotonin. As you can see on the diagram below, there are many nutritional elements which have a co-factor role in the pathway from protein to serotonin. Vitamin B1, Vitamin B6, zinc, calcium, vitamin C, magnesium and even adequate stomach acid are all essential for the conversion of tryptophan into serotonin.

The Austrian study included 50 patients with diagnosed lung cancer. Blood samples examined various markers such as C-reactive protein which is an indicator for inflammation. Tryptophan and kynurenine levels were compared to a range of blood markers, including those that are commonly used to assess anemia. Questionaires were also completed by the patients to explore fatigue levels and indicators quality of life.

Fighting Spirit vs Increased feelings of Hopelessness in Cancer

The study found patients with “higher fighting spirit” had lower fatigue. The opposite type of patients with “higher feelings of hopelessness” had higher fatigue. Positive acceptance and changes as a result of the cancer correlated with lower fatigue whereas negative adjustments to the cancer correlated with higher fatigue.

Blood serum levels of tryptophan were lower in patients with cancer than healthy controls. The tryptophan did not relate to the stage of the cancer but it did correlate with the survival time. Higher tryptophan and lower kynurenine levels had a strong relation to the patient survival time. Furthermore patients with a higher C-reactive protein and low haemoglobin level had a lower level of survival after 3 months.

Survival in Cancer

To summarise, high inflammation, high kynurenine, low tryptophan and low haemoglobin levels correlate to greater fatigue and lower quality of life. It would suggest that maintaining optimal blood cell health and oxygen carrying capacity may prove beneficial to cancer patients. Furthermore maintaining optimal serotonin production and conversion of tryptophan may also prove beneficial to survival.

Possible Recommendations

Based on the findings it may be beneficial to consider the following-

  • keep digestive secretions optimal
  • Ensure adequate intake of zinc, vitamin C, Vitamin Bs, magnesium
  • Bring in activities that support a positive mind such as meditation or sports
  • Surround yourself with family and friends to maintain a high quality of life

The study found that patients with higher levels of fatigue had a lower quality of life. Herbal medicine that supports energy levels and quality of sleep will have a flow on effect and benefit to patients.

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