A potassium deficiency cannot cause warts.
More Info: Though a potassium deficiency is not directly responsible for causing warts, it can be a contributing factor to outbreaks. Maintaining good health and hygiene practices is important for fighting off viruses such the one that causes warts and getting the right amount of potassium in your diet will help you toward that goal.
What causes Warts?
Warts are caused by the human papilloma virus (HPV). There are more than 150-recorded strains of this virus, seventy-five percent of which cause common warts. HPV attacks the epithelial cells, the outside layer of cells that cover all areas of the skin and mucous membranes. It can take up to six months for the visible signs of the virus to appear on the skin. 
How Do You Get Warts?
Like any virus, you can contract HPV by coming into contact with it. People with skin breaks, such as cuts or hangnails, are more likely to contract the virus. You can catch it from person-to-person contact, such as shaking hands with someone who has it. It can also live on surfaces, so you can catch it from a towel or a shower floor. To prevent catching the virus, wash your hands regularly, don’t bite your nails, and always wear rubber shoes in public showers. 
Mineral Deficiencies and the Immune System
A healthy immune system is important for fighting off viruses such as HPV, which includes getting the right amount of vitamins and nutrients every day. Though there are very few studies that directly tie diet and mineral deficiencies to immune system function, emerging research is indicating that some deficiencies may impact the immune system more than others. Emerging studies have provided some evidence that vitamins A, B6, C, E, copper, folic acid, iron, selenium, and zinc alter immune responses in animals. 
Potassium’s Role in the Body
Maintaining good health and hygiene practices is important for fighting off viruses such as HPV and getting the right amount of potassium in your diet will help you toward that goal. Potassium is important to the healthy functioning of cells, nerves, and muscles. Adults 19 and older can get the recommended 4,700 milligrams per day readily through a healthy diet that includes potassium rich foods such as bananas, oranges, tomatoes, potatoes, flounder, salmon, and chicken. 
What Is a Potassium Deficiency?
Though warts are not a common symptom of a potassium deficiency, a severe deficiency has recognized symptoms. Known as hypokalemia, a severe potassium deficiency can cause dysrhythmias, rhabdomolysis, muscle weakness or spasms, constipation, fatigue, and paralysis. 
 American Cancer Society
What Is HPV?
What Causes Common Skin Warts?
 Harvard Health Publications-Harvard Medical School
How to Boost Your Immune System
University of Maryland Medical Center
 US National Library of Medicine
National Library of Medicine-National Institutes of Health
Potassium in Diet
Glossary of Terms
Dysrhythmias-Abnormal heart rhythms
Rhabdomyolysis-Breakdown of muscle fibers
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