Meal Timing
We have reviewed above that volume expansion can be important for individuals with POTS, given the reduced blood and plasma volume many in our community have, so it should not be surprising why anything that reduces the circulating blood volume may worsen symptoms. This explains, in part, why individuals in our community can experience symptom flares after eating large meals, especially if they are carbohydrate dense.
Provider recommendations often involve suggesting that individuals in our community eat smaller meals more often throughout the day (to avoid eating very large meals), but why exactly is this (Pots: Causes, symptoms, (n.d)? On top of the splanchnic pooling many in our community may have, postprandial hyperemia (the significant increase in blood flow to the gastrointestinal tract after eating) reduces our circulating blood volume (Stewart et al., 2006; Kvietys, 2010).
This explains why providers such as Dr. Coleby may suggest reducing meal size in an effort to (hopefully) reduce the severity and overall impact postprandial hyperemia would have on individuals in our community who may already be struggling to maintain adequate blood volume at baseline (Coleby, 2022).
Sources:
Coleby, C. (2022, October). Non-Pharmacologic Treatment Overview. POTS & Beyond. Salt Lake City; Utah.
Kvietys, P. (2010). Chapter 5 Postprandial Hyperemia. In The gastrointestinal circulation. essay, Morgan & Claypool Life Sciences.
Pots: Causes, symptoms, diagnosis & treatment. Cleveland Clinic. (n.d.). Retrieved November 12, 2022, from https://my.clevelandclinic.org/health/diseases/16560-postural-orthostatic-tachycardia-syndrome-pots
Stewart, J. M., Medow, M. S., Glover, J. L., & Montgomery, L. D. (2006). Persistent splanchnic hyperemia during upright tilt in postural tachycardia syndrome. American Journal of Physiology-Heart and Circulatory Physiology, 290(2). https://doi.org/10.1152/ajpheart.00784.2005