Garlic & the Low FODMAP Diet
There seems to be a bit of confusion around how to use garlic safely on the low FODMAP diet. So this article is going to discuss why garlic is a problem, and how you can safely add garlic flavour to your meals without causing tummy troubles.
Why is garlic a problem on the low FODMAP diet?
Garlic contains fructo-oligosaccharides, which are commonly referred to as fructans (Mansueto et al., 2015; Monash University, 2015). Fructans are short chain carbohydrates and are found in foods like onions, garlic, wheat, rye, barley, and artichokes (Mansueto et al., 2015 Monash University App, 2014). Humans do not have enzymes to break down either of the oligosaccharide sugar groups, which means they are malabsorbed in the small intestine, and then fermented by the gut bacteria, leading to irritable bowel syndrome symptoms (Mansueto et al., 2015; Monash University App, 2014). This is why when you eat garlic, you can end up with unpleasant symptoms. It is recommended that you remove garlic from your low FODMAP diet during the elimination phase (Monash University, 2015). You can then test garlic in the reintroduction phase, to see if you can add small amounts back in.
How do you replace the garlic flavour while eating low FODMAP?
Garlic infused oil is a tasty and safe replacement for garlic in low FODMAP meals. The fructans present in garlic are only water-soluble and not oil soluble (Scarlata, 2015). This means the garlic flavour transfers into the oil while the fructans stay trapped in the garlic cloves, as there is no water in the oil for them to leech into (Scarlata, 2015). According to Monash University, garlic infused oil should be well tolerated by most people on the low FODMAP diet (Monash University, 2015).
Where do you find garlic infused oil?
There are two ways you can get garlic infused oil. First you can buy it from the supermarket. It is normally found in the oil section and will last several months. Garlic infused oil is relatively strong, so normally you won’t need to add too much to the recipe to get the flavour.
The second way to get garlic infused oil is to make your own. You need to peel and cut the garlic into large pieces. You then fry the garlic in the oil for 1 to 2 minutes over low to medium heat, to transfer the flavour. Next remove all of the garlic (including any small fragments) from the pan before cooking the rest of your meal. It is important that you remove all the pieces of garlic from the pan, otherwise you will ingest higher levels of fructans. Then cook the rest of your meal in the oil.
Can making your own garlic infused oil be dangerous?
A word of warning if you are going to make and store your own garlic infused oil. Garlic can contain a microorganism (bacterium) called Clostridium botulinum (C. bot), which can cause botulism (CDC, 2014; University of Maine, 2011). Botulism is a rare but serious paralytic illness caused by a nerve toxin that is produced by the bacterium (CDC, 2014; University of Maine, 2011). This bacteria strain is found in soil and thrives in low oxygen environments, which means homemade oil can become contaminated with the bacteria (CDC, 2014; University of Maine, 2011).
Commercially made garlic infused oils are acidified to prevent bacterial growth during the production process (University of Maine, 2011). This means that commercially made oils can be stored at room temperature (University of Maine, 2011).
So if you do decide to make a batch of homemade garlic infused oil there are some steps you need to take to keep yourself safe:
- Wash and dry the garlic thoroughly before cooking – dry using clean paper towels so you don’t transfer any additional bacteria.
- Store the oil in a sterilised jar or bottle. Preheat your oven to 110ºC. Wash the jar and jar lids in hot soapy water. Transfer them to a baking tray lined with clean a tea towel, placing the jar open side up. Place in the oven for 25 minutes before removing.
- Once cooked, fill your sterilised jar with garlic infused oil and refrigerate immediately. Put a label on it with the date. Keep the oil in the fridge. You must use it within 7 days.
Why can’t you just take out the garlic before you eat the meal?
Unfortunately, when you cook with garlic, the fructans can leech from the garlic into other parts of meal, as they will dissolve in any water that is present in the other ingredients you are cooking. While not eating the garlic pieces will reduce your overall FODMAP load, it may not reduce it enough, as the fructans will have become infused in other parts of the meal. Therefore, in the elimination period you need to either avoid garlic, or use safe garlic infused oil. After the reintroduction period, you might find you can tolerate leaving the garlic pieces in whole and then remove them before eating, but you need to test garlic in the reintroduction phase first.
Watch out for sneaky garlic!
Garlic is often added to processed foods like dips, spice mixes, chips, and gravy. This means it is important to check food labels, and avoid any products that contain garlic based ingredients.
I use a lot of garlic infused oil in my cooking and highly recommend it to help achieve garlic flavour. However, if you are worried about making it yourself stick to the store bought garlic infused oils.
Happy cooking everyone!
1. Mansueto, P., Seidita, A., D’Alcamo, A., Carroccio, A. Role of FODMAPs in Patients with Irritable Bowel Syndrome: A Review. Nutrition in Clincial Practice Journal. 2015-02-18. DOI:
2. Monash University. Frequently Asked Questions. Monash University Low FODMAP Website. 2015. Retrieved from:http://www.med.monash.edu/cecs/gastro/fodmap/diet-and-ibs.html#5. Retrieved on: 2015-03-09. (Archived by WebCite® at http://www.webcitation.org/6WuTAniFE)
3. Monash University App. About Section & Food Guide. The Monash University Low FODMAP Diet App. 2014: Edition 4. Date retrieved: 2015-03-05. Retrieved from :http://www.med.monash.edu/cecs/gastro/fodmap/iphone-app.html. Accessed: 2015-03-05. (Archived by WebCite® at http://www.webcitation.org/6Wog73c8B)
4. Scarlata, K.. FAQs. Well Balanced. 2015. Retrieved from :http://www.katescarlata.com/faq/. Retrieved on: 2015-03-16. (Archived by WebCite® at http://www.webcitation.org/6X488vTpB)
5. CDC. Botulism. 2014. Retrieved from http://www.cdc.gov/nczved/divisions/dfbmd/diseases/botulism/ Retrieved on: 2015-03-16.
6. University of Maine. Food Safety Facts: Safe Homemade Flavoured & Infused Oils. University of Maine. 2011. Retrieved from:http://umaine.edu/publications/4385e/. Retrieved on: 2015-03-16. (Archived by WebCite® at http://www.webcitation.org/6X48npLno)