Fasting is defined as receiving no food and subsisting on only water or liquid for one to five days, the American Cancer Society says. People who fast sometimes take tea or broth in addition to other liquids for the duration of the fast. Fasting for even a short period of time may cause health problems, which sometimes manifest as rashes if the fasting has led to malnutrition. Malnutrition causes skin problems because of vitamin and mineral deficiencies, DermNetNZ.org explains.
Types of Rashes
Skin rashes make your skin red, swollen, dry and itchy, KidsHealth.org notes. Rashes sometimes include lumps, bumps and blisters. Hives is a kind of skin rash that is often a symptom of an allergic reaction. Hives manifest as pale or reddish sections of swollen skin caused by the release of histamine. Histamine is a chemical your body releases in response to an allergen. Hives are also caused by viral infections. Eczema is a type of rash that is common in children. It is characterized by dry, chapped and bumpy patches of skin around the elbows and knees. More serious cases of eczema involve red, swollen skin all over the body. Irritant contact dermatitis occurs when skin makes contact with an irritant such as a poison, chemical, bath soap or detergent.
Vitamin C Deficiency
Fasting that causes vitamin C deficiency will cause skin rashes, the University of Maryland Medical Center explains. Vitamin C is a water-soluble vitamin, so your body is unable to store it like vitamins that are fat-soluble. Vitamin C is involved in the growth and repair of tissue. Your body uses vitamin C to make collagen, a protein vital to the production of skin, tendons and ligaments. Vitamin C deficiency causes skin rashes that are rough, dry and scaly.
Iron Deficiency
Malnutrition sometimes causes iron deficiency. Iron is a mineral necessary for your red blood cells, which help keep your skin nourished. A deficiency of iron causes your skin to become pale, dry and itchy, MedlinePlus, a service of the National Institutes of Health, notes. This is because without sufficient levels of iron, your skin is unable to stay properly nourished.
Impaired Thyroid Function
Fasting is dangerous to people who are already malnourished. Sometimes fasting induces malnutrition to such a degree that your thyroid function is impaired. Impaired thyroid function causes your skin to become dry and potentially break into rashes, DermNetNZ.org notes.
References
- American Cancer Society; Fasting; November 2008
- DermNetNZ.org; Malnutrition Including Anorexia Nervosa; Marie Hartley; June 2011
- KidsHealth.org; Rashes; Patrice Hyde; February 2008
- MedlinePlus; Itching; Linda J. Vorvick; June 2010
- University of Maryland Medical Center; Vitamin C; Steven D. Ehrlich; June 2009
