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Preventing Weight Loss on the Low FODMAP Diet

The Low FODMAP Diet is not intended to be a weight loss diet. The low FODMAP diet is an elimination diet that is intended to be followed for a short period of time to identify food triggers for IBS. While following an elimination phased diet, it is advised to be followed by a health professional, such as a Registered Dietitian Nutritionist to avoid unintended weight loss and nutritional deficiencies.

What is an elimination diet?

An elimination diet is a methodical approach that requires people to cut out foods for a short period of time that are likely related to physical symptoms such as: gas, bloating, diarrhea, constipation, and other symptoms. Elimination diets, including the Low FODMAP diet, is a multi-phased approach to have a clear understanding of your food triggers.

Phase 1:

Elimination Phase:

The elimination phase is intended to eliminate likely trigger foods for ONLY two to six weeks, until symptoms greatly improve. During this phase, you are at greater risk for nutrient deficiencies due to nutrient rich foods being eliminated. This is why it is important to make sure you are being managed by a Registered Dietitian who can help prevent nutrient deficiencies by recommending alternative foods to consume or supplements as needed to meet your nutritional needs.

Phase 2:

Reintroduction Phase:

The reintroduction phase is to be started after symptoms have greatly improved, and you are ready to start challenging the eliminated foods in a methodical way to identify your threshold of each FODMAP group. The elimination phase is meant to be continued while you challenge one FODMAP group at a time.

Again, this is not intended to be a weight loss diet, and many people with IBS or other digestive issues are already at a lower weight for their body frame, and can't risk losing more weight. Make sure to follow these tips to at least maintain your weight, if not regain some weight as well.

Tips to Maintain your weight:

Eat frequently:

Having regular meal and snack timings can help with meeting your caloric needs. It can be difficult for some to meet their needs through 3 meals per day, so think of increasing to 6 small meals per day by spreading foods out every 3 hours to still allow time for food to digest prior to your next meal timing.

Increase Calorie Dense Foods:

You can increase your calories without increasing the volume of food since your stomach might not be able to handle a larger volume in one sitting. In order to increase calories aim for calorie dense foods such as:

  • Nuts: Peanuts, Pecans, Brazil nuts, macadamia nuts, pine nuts, walnuts, and nut butters.

  • Seeds: chia, ground flaxseed, pumpkin seeds, hemp seeds, sunflower, seed butters.

  • Fats: olive oil, canola oil, avocado oil, butter.

  • Fatty Fish: salmon, tuna, mackerel.

  • Proteins: eggs, chicken, turkey, beef, pork

  • Dairy: If you are able to tolerate lactose add yogurt and cheeses. Aim for the full fat sources for added calories. You can talk to your dietitian if you need to watch saturated fats for your heart health.

Add a topper:

You can sprinkle on nutrient dense foods on top of dishes to increase calories as well, such as:

  • Cheese or sour cream onto potatoes or vegetables. If you are unable to tolerate dairy opt for dairy free sources.

  • Add chia, flaxseed, nuts, granola, maple syrup, coconut flakes onto yogurts or smoothies, or oatmeal.

  • Add nut butters, seeds, nuts, and fruit onto toasts or pancakes.

Consider smoothies or shakes:

You can increase your calories from drinks as well. Ideally you want the calories from nutrient rich foods such as a smoothie that has milk or milk alternative such as almond or soy milk for calcium and vitamin D, fruits, and vegetables, and you can add protein from a protein powder, and/or peanut butter. And top it off with ground flaxseed, chia seeds, oats, coconut flakes, or slivered almonds. There are also ready made meal replacement shakes that are handy to take on the go.

Focus on fluids around meal times:

To get the nutrient dense foods in at meal times, make sure to not drink a lot of water at the meal. Use water sparingly to wash your foods down at meals. Put your primary focus on the food on your plate to help ensure you meet your calorie needs.

Add Strength Training:

Consider adding strength training to your exercise regimen at least 2-3 days per week. Strength training can help promote muscle gain, as well as help to stimulate your appetite.

If you feel overwhelmed by figuring out the best foods for your body, please reach out to discuss meal planning options for your personal nutritional needs.

Schedule a free discovery call today at:


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