If you follow a vegetarian or vegan diet, there are some important nutrients your diet may lack. These include calcium, protein, iron, zinc, vitamin B6 and B12. These can become deficient in a vegetarian/vegan diet due to animal products being the best sources, nutritionally speaking. If you also require a low FODMAP diet to manage IBS, getting enough of these nutrients proves even more challenging.
So is it possible to achieve a nutritionally balanced low FODMAP vegetarian/vegan diet? In short, yes – but it needs to be done properly.
First, a note on nutrient absorption
Before we take a look at some food sources of the above mentioned nutrients, it is important to discuss nutrient absorption. Since the absorption of certain nutrients in vegetarian/vegan food sources isn’t as good, it’s important to be particularly mindful of including these in your diet.
Calcium in lactose-free dairy products and vegan products is not as well absorbed as regular dairy products. Similarly, iron from non-meat sources is not nearly as well-absorbed as iron from meat sources. So even though you may be eating something that contains 200mg calcium, you may be only absorbing say 50mg of calcium.
Calcium is crucial in bone health, and reduces risk of diseases like osteoporosis. Getting enough calcium can be particularly tricky for vegans, given dairy products provide a major source of calcium. Since lactose is also high in milk products, calcium is a nutrient which can also commonly lack in a vegetarian and omnivorous low FODMAP diet. Below are some low FODMAP vegan and/or vegetarian calcium sources:
- Fortified soy milk made from soy protein (not from soy beans) such as ‘So Good’
- Fortified almond milk
- Soy cheese
- Lactose-free milk
- Lactose-free yoghurt
- Green leafy vegetables such as spinach, broccoli, bok choy
- Some low FODMAP nuts, such as brazil nuts.
Protein plays an important role in building and repairing our muscles. In Australia we tend to quite easily meet our protein requirements without much difficulty, although without meat and/or animal products in the diet, protein is an important nutrient to be mindful of. Below are some low FODMAP vegan and/or vegetarian protein sources:
- Dairy alternatives (above)
- Quorn mince (watch out for added garlic/onion)
- Firm tofu
- Low FODMAP nuts such as walnut, brazil nuts, pecans, macadamias and pine nuts.
- Seeds such as chia seeds and linseed
- Low FODMAP vegan/vegetarian protein powders – see our recent article here for details
- Legumes – whilst legumes can be high FODMAP in large quantities, there are still low FODMAP serves. Most people with IBS should be able to tolerate 1 serve of the following per day:
-Tinned lentils (1/2 cup)
-Canned chickpeas (1/4 cup)
-Canned black beans (1/4 cup)
-Butter beans (1/4 cup)
-Boiled red/green lentils (1/4 cup)
-Lima beans (1/4 cup)
-Mung beans (1/4 cup)
Iron is particularly important for pre-menopausal women, who have nearly triple the iron requirements of adult males (or quadruple if pregnant!). The iron requirements for vegetarians/vegans is even higher, as iron from non-meat sources (known as non-haem iron) is not nearly as well absorbed as iron from meat (haem iron). So iron is an important nutrient to keep an eye on if not eating meat. Below are some low FODMAP vegetarian and/or vegan sources of iron. These are good to combine with vitamin C, found in fruit and veg, to increase its absorption.
- Tinned lentils
- Low FODMAP nuts and seeds
- Soy products such as soy milk (from soy protein), soy cheese and tofu/tempeh.
B12 helps maintain a healthy brain and healthy cells, by producing red blood cells. B12 is only found in animal products, such as meat and dairy products. Low FODMAP vegetarians can therefore get sources of B12 from eggs, cheese, and lactose-free milk/yoghurt. Vegans, however, may require B12 supplementation/injections. If you are concerned, discuss this with your GP. It may be a good idea to get a routine blood test every 6 months or so, to check nutrient levels such as B12 and iron.
Zinc is important in immunity (helps fight off sickness) and found largely in meat products. Below lists some low FODMAP vegan and/or vegetarian zinc sources:
- Low FODMAP nuts
- Tinned chickpeas ( ¼ cup) and tinned lentils
Vegetarians who still eat seafood
If you are vegetarian or simply dislike meat, but still eat seafood, then fish is a good source of the nutrients just covered. Seafood like oysters are a particularly good source of zinc. Sardines and tinned salmon (with the bones crushed up) also provide an excellent source of calcium.