Researchers have yet to discover the direct cause of ulcerative colitis; however, there are a number of possible factors which may contribute to the manifestation of this disease. They include:

Genetic factors

genetic factorsGenetic factors have a certain influence on the development of ulcerative colitis. This was hypothesized due to the following information:

  • Identical twins have 10% concordance rate (if one of the twins has ulcerative colitis, then there is a 10% chance that the other will also have ulcerative colitis) and dizygotic twins have a 3% concordance rate.
  • There a slightly higher chance of one family member to get ulcerative colitis if the other family member is also affected by it.
  • Some ethnicities are more predisposed to ulcerative colitis than others. Most commonly ulcerative colitis is diagnosed among the Caucasians, while Asians are the least likely to have ulcerative colitis.


Environmental factors

Certain environmental factors increase or decrease the chances of the person getting ulcerative colitis. They include:

unhealthy diet

  • Diet
    Since our digestive system is exposed to a vast array of dietary substances which may cause an inflammation, it was hypothesized that they may cause ulcerative colitis and Crohn’s disease. Unfortunately, not a lot of studies were done on this topic.

    The only information that is available is that:

    • Refined sugar – has no effect on the development of ulcerative colitis;
    • High intake of vitamin B6 and unsaturated fats – increase the chances of having an ulcerative colitis. However, the cause of it is unknown;
    • Alcoholic beverages and meat protein – may trigger the relapse or the development of the ulcerative colitis. Probably, due to the fact that alcoholic beverages can directly damage the inner lining of the large intestine, while meat proteins under the influence of gut bacteria release a number of toxins which may cause slight irritation to the mucous layer.
  • Breastfeeding

    Breastfeeding serves a number of functions aside from its nutritional value. Children that were breastfed for more than one year, in comparison to those that weren’t breastfed at all or were breastfed for only a few months, show an increased resistance to a number of diseases including ulcerative colitis (as shown by one Italian study), Crohn’s disease, Type II diabetes, a number of other conditions.

  • Acne treatment

    Several studies have shown that acne treatment using Accutane (isotretinoin) may lead to ulcerative colitis and Crohn’s disease in some individuals.

  • Autoimmune disease

    Ulcerative colitis is characterized by infiltration of the colon with T-cells. Unlike Crohn’s disease, it does not affect other regions of the gastrointestinal tract and is found usually in rectum, sometimes affecting colon and occasionally distal part of ileum. In some cases, the disease can affect the entire colon which is called pancolitis. In such cases, surgical removal of the entire colon is sometimes necessary.

  • Alternative theories

    Quite often, people that have ulcerative colitis have a decreased amount of sulfate-reducing bacteria. This causes levels of hydrogen sulfide to rise and damage the interior lining of the intestine.