The Low-FODMAP Diet Phase III: Personalization & Beyond

Looking Long-Term

The aim of phase III is symptom control and a Registered Dietitian can provide important educational, as well as motivational, support.

Counseling patients in phase III often involves an emphasis on helping patients avoid common mistakes when developing and following their personalized diet. Even once patients identify triggers in phase II, creating a liberalized, long-term diet in phase III can feel overwhelming and frustrating. Loss of motivation and the temptation to “cheat” can occur, while internalization of food fears and reluctance to add new foods may also arise.

Avoid FODMAP Stacking

FODMAP stacking occurs when foods in the same green or yellow FODMAP category are eaten together. Patients who continue to experience flare-ups despite following a low FODMAP diet may be overlooking the total amount of FODMAPs they’re consuming at a single meal or snack.

When getting to the root of flare-ups, encourage patients to track the total number of green or yellow FODMAP portions they’re having at a sitting. Common green foods that become moderate or high FODMAP in larger portions include sweet potato, eggplant and cabbage. However other low FODMAP foods, such as carrot and strawberries, are green regardless of the portion size.

Spacing out meals and snacks by 3-4 hours helps avoid FODMAP stacking because it allows food to move through the digestive tract. Mixed dishes with multiple fruits and vegetables can also increase risk for FODMAP stacking. For example, fruit salad can easily become high in fructose and/or sorbitol. Have patients pair green or yellow FODMAP foods with FODMAP ‘free foods’ like arugula, bell pepper, bok choy, cucumber, kale, radish, potato, scallion tops and spinach to prevent additive effects of FODMAPs.

A few recommended low FODMAP vegetable and fruit combinations include: 1) zucchini, cabbage and red pepper; 2) eggplant, snow pea and edamame; 3) corn, sweet potato, zucchini and red pepper. Download our free Phase III Guide to The Low FODMAP Diet for an easy-to-use algorithm to help patients build low FODMAP combinations based on their favorite vegetables.

Ensure Nutritional Balance

While nutrient deficiencies are a greater concern during the more restrictive phases I & II of the low FODMAP diet, phase III poses an ideal time to optimize nutritional intake. Whether patients present with concerns around micro- or macronutrient deficiencies or not, education on common nutrients of concern can be helpful. These include total energy, calcium, fiber and carbohydrate intake, as well as thiamine and riboflavin (especially among patients who end up needing to restrict lactose). Share strategies to consume enough of these nutrients, such as low-lactose dairy, fortified plant-based milks and fortified, high-fiber grain products.

Research to date is mixed on whether a low FODMAP diet changes the microbiome and if this should be a concern [1]. Among studies that do observe microbiome changes, findings are not clinically significant. Notably, however, research does suggest a low FODMAP diet reduces Bifidobacteria and that probiotic supplementation with a Bifidobacteria strain may help maintain overall Bifidobacteria abundance and reduce symptoms [2]. In addition, the low FODMAP diet has also shown to reduce saccharolytic bacteria, which are associated with a higher symptom burden and greater response to the low FODMAP diet [3]. Lastly, there is some thinking that the low FODMAP diet may in fact work by altering the microbiome, especially in patients with dysbiosis. Until more research reveals this complex mechanism, assure patients that concerns around microbiome changes are unnecessary while on a long-term, personalized low FODMAP diet.

Troubleshooting

While a low FODMAP diet can help control symptoms, diet and lifestyle factors are important in symptom control and long-term gut health. Eating style, sleep, medications and non-FODMAP foods can all contribute to symptoms. Chronic stress and elevated adrenal hormonal levels disrupt digestion in a multitude of ways, including inhibition of intestinal cleansing waves, suppression of the immune system and disruption of gut microbiota. This can lead to dysbiosis, chronic inflammation and leaky gut [4,5]. While addressing food sensitivities and intolerances are a cornerstone of symptom management, alternative therapies and supplements can play an important role in restoring digestive health.

Once patients are reliably following a low FODMAP diet, begin discussing how to address other underlying digestive and health conditions. These root causes may need to be addressed to achieve adequate symptom relief. Resolution of underlying hormonal imbalances, dysbiosis, chronic inflammation and other issues leading to inadequate digestion (such as low HCL, enzyme levels, or bile) can be achieved through a holistic, interdisciplinary approach.