No, what I was trying to say is there are different ways someone can have a reaction to a food and that most doctors will test with only one of those ways (IgE). For example, someone may get a skin prick test with gluten or dairy and show up negative with IgE but if tested with IgG would show a positive reaction to that food. One may get blood testing for this, but truly one of the best ways to find out is to just cut out a food and re-introduce it a month later. Many with autoimmune conditions try the AIP diet and find it works wonders for their symptoms. Many with gut issues try the SCD or GAPS diet and find it is extremely beneficial. The IBS diet can be pretty beneficial at first especially if the individual has SIBO, but the only downside is those fermentable foods provide nutrition to our gut biome in the colon. The gut biome has huge impacts on human health ranging from the immune system, mental health, hormones, etc., so while it could be helpful at first it could be harmful in the long run. The important thing is that someone with POTS may find helpful, as well as other dysautonomias, is to find their inflammatory triggers as inflammation causes an increase in IL-6 which can increase the tone of the sympathetic nervous system