Problems with your immune system. A Candida infection can cause an auto-immune disorder, or if you have an existing auto-immune disorder, it can be made considerably worse if you’re also suffering from a yeast infection. You must be especially careful if you have conditions such as Multiple Sclerosis or Arthritis because the effects of these can be magnified by Candida. Some studies have shown a similar reaction to a protein in Candida, as that which some people exhibit to gluten. It has also been shown that fibromyalgia, and other serious health issues such as chronic fatigue syndrome, are both very closely related to a Candida infection.