In a study published in Infectious Agents and Cancer journal, researchers found that taking cold showers increases the production of disease-fighting white blood cells, which results in a stronger immune system.
Researchers delved deeper into the phenomenon of hormesis, where small amounds of seemingly harmful or stressful facts can be beneficial for the health – like showering with cold water that so many of us find uncomfortable and tortuous, especially in the mornings.
Daily exposure to brief cold stress can increase numbers and even activity of peripheral cytotoxic T lymphocytes and white blood cells, which help us fight diseases.
Researchers believe repeated cold stress appears to involve transient activation of the sympathetic nervous system, hypothalamic-pituitary-adrenal and hypothalamic-pituitary-thyroid axes. Daily moderate cold hydrotherapy is known to reduce pain and does not appear to have noticeable adverse effects, although some studies have shown that it can cause transient arrhythmias in patients with heart problems and can also inhibit humoral immunity. Sudden immersion in ice-cold water can cause transient pulmonary edema and increase permeability of the blood-brain barrier, thereby increasing mortality of neurovirulent infections.
So next time you jump into the shower, don’t be afraid of cold water, it might just do more for your health than your brief moment of discomfort.
Possible stimulation of anti-tumor immunity using repeated cold stress: a hypothesis. Infectious Agents and Cancer. 2007 Nov 13;2:20.