Dietitian Jackson debuts with a robust program for managing irritable bowel syndrome. Explaining the biology of the condition, she points to research showing that people with IBS have an overactive fight-or-flight response, which evolved to either speed up bowel movements ("making you 'lighter on your feet' ") or slow down colon contractions, allowing "energy to be expended elsewhere." Throughout, Jackson adds nuance to standard nutritional guidance. For instance, she contends that conventional wisdom urging people with IBS to steer clear of dietary fiber ignores the distinction between high and low fermentable sources of fiber, the latter of which (e.g., quinoa, spinach, and walnuts) can help regulate bowel movements without feeding harmful gut microbes. In addition to the usual suggestions to get enough sleep and exercise 30 minutes every day, Jackson tackles less commonly addressed aspects of living with the condition, as when she offers tips for discussing IBS with one's partner (be open about having the condition, but "you don't have to talk all things IBS straight away") and dining out (cuisines "with fewer ingredients and flavourings" tend to have more IBS-friendly options). In addition to offering detailed dietary guidance, Jackson, who has IBS, demonstrates a keen understanding of how the condition can affect one's social life. This stands out in the crowded field of IBS manuals. (July)