Oats - this one’s just right!

Over the last few weeks, we’ve been writing about the fibre sources featured in our Best Ever Poop Program. This week we talk broadly about good sources of soluble fibre, but we’re zooming in on one of my favourite fibre-rich foods - oats.

Porridge has a special place in my heart. It is as old as time, the stuff of fairy tales and is warming on a cold winter morning. It has always been my father’s go to breakfast. He even has a special spoon called a spurtle for stirring his porridge as it cooks. Altogether, that means I have a massive soft spot for all things oats, which is good because they have some amazing health benefits.

Oats and the perfect poop

Oats are rich in a type of soluble fibre called beta-glucan. It is gel-forming in the gut and great for softening and bulking up the stool as well as feeding good gut bacteria. It is helpful for people with either constipation or diarrhoea.

Soluble fibre is much more easily fermented by your good gut bacteria than insoluble fibre. The bacteria convert it to beneficial short chain fatty acids (SCFAs). These can be rapidly absorbed by the cells lining the large intestine and used as an energy source. Absorption of SCFAs by the colon cells also affects movement of water and ions reducing symptoms of diarrhoea.

What are other good choices if you have IBS-D

If you’ve checked out our Pest Ever Poop Program you will have read that there are lots of options for people with constipation, but it is tougher for people with diarrhoea to find appropriate fibre-rich foods. They typically need to have soluble fibre that forms a gel and bulks up the stool, but avoid insoluble fibre that speeds up movement through the gut.

Lots of foods (fruit, vegetables, beans and nuts) have both types of fibre. The options with mostly soluble fibre are limited. Soluble fibre comes in the form of beta-glucan, pectin, gums, mucilage, fructans, and some resistant starches. If you have IBS and want to avoid bloating, you’ll want to skip the  fructans. Many high pectin fruits like apples and pears also contain high levels of the FODMAPS fructose and sorbitol. So what does that leave?

What are some other options?

1.      Psyllium* contains mucilage that like oat beta-glucan absorbs water in the gut to form a gel. Try adding a teaspoon to your breakfast, whether that’s fruit and yoghurt or muesli.  

2.      Ground chia* also contains mucilage that forms a gel. It is best soaked in liquids such as lactose-free milk or coconut milk before eating.

 3.      Partially hydrolysed guar gum* is a soluble fibre that feeds your good gut bacteria, normalises stool form and help food move through the gut at just the right pace. The hydrolysation of the guar gum means easily dissolves in water than regular guar bean gum or acacia gum and is less viscous (thick). It won’t slow gut transit time as much as other types of soluble fibre, so it a suitable for people with gastroparesis.

4.      White rice contains resistant starch, a type of soluble fibre that is great for your gut microbiome.

5.      Carrots and Kent pumpkins are relatively high in soluble fibre (pectin) compared to other vegetables, and are usually well tolerated by people with IBS.

*found in Superflora shakes

Other benefits of the soluble fibre in oats

The beta-glucan found in oats may also help lower and stabilise blood glucose levels especially in people with obesity or who have type 2 diabetes.

These effects are mainly attributed to beta-glucan’s ability to form a thick gel that delays the emptying of the stomach and absorption of glucose into the blood.

Oats can also help improve heart health. A key risk factors in the development of heart disease is high blood cholesterol. Many studies have shown that the beta-glucan fibre in oats is effective at reducing both total and LDL (bad) cholesterol levels.

There are likely several mechanisms at play. Soluble fibre ‘soaks’ up some of the cholesterol in the diet and bile preventing it from being absorbed in the small intestine. The gut microbiome also plays a role converting the fibre into SCFAs including propionic acid, which can decrease the amount of cholesterol made in the liver.

Other goodies

Oats are incredibly nutritious. Along with the fibre, they are a good source of complex carbohydrates, and also contain protein. Half a cup of rolled oats will provide over 5 g of protein. If you are vegan or just looking to up your protein intake, add a spoonful of oats and a spoonful of peanut butter to your Superflora Shakes to sky rocket your protein intake.

Oats are a good source of B Vitamins including folate and minerals, particularly manganese.

Whole oats are also rich in antioxidants, in particular, they contain a type of polyphenols called Avenanthramides, which have both antioxidant and anti-inflammatory effects.

Soaking or cooking oats makes the nutrients more bioavailable.

Fodmaps and oats

Oats do contain fructans and GOS, but at only at low levels, so that are fairly big low FODMAP serving sizes. The degree of processing has an effect on this. 

• Groats (uncooked)  - ¼ cup or 60g

• Rolled oats (uncooked) – ½ a cup or 52g

• Quick oats (uncooked) – ¼ cup or 23g

We take into consideration taste, texture and FODMAP content when choosing our oats. We are like Goldilocks and go for the one in the middle. Rolled oats don’t cook as quickly as quick oats, but they have fewer FODMAPs, and they aren’t as tough and chewy as groats.

Gluten and oats

Oats can be a problem for people with coeliac disease for two reasons:

• Oats can be contaminated with wheat, rye or barley that contain gluten and

• Oats contain a protein called avenin similar to gluten that can also cause gut inflammation for some coeliacs. Avenin is present at only low levels in oats, but it can cause problems for up to 10% of people with coeliac disease.

You might want to swap oats for a rolled rice or a quinoa flake porridge.

When porridge isn’t porridge

Watch out for some of the added extras in the porridges on supermarket shelves. A few chia seeds works well, but we’ve seen added faba bean protein and inulin that can cause painful bloating.

If you want variety, try adding a little cocoa powder or even stir through some Superflora at the end of cooking. Check out our luxurious porridge recipe that works well with any low FODMAP milk and Rich Cocoa Chocolate Superflora or Plant-based Chocolate Superflora. Enjoy!

References

Zurbau, A., Noronha, J. C., Khan, T. A., Sievenpiper, J. L., & Wolever, T. M. S. (2021). The effect of oat β-glucan on postprandial blood glucose and insulin responses: a systematic review and meta-analysis. European journal of clinical nutrition, 75(11), 1540–1554. https://doi.org/10.1038/s41430-021-00875-9

Soliman G. A. (2019). Dietary Fiber, Atherosclerosis, and Cardiovascular Disease. Nutrients, 11(5), 1155. https://doi.org/10.3390/nu11051155

Written by: Dr Mary Webberley, Chief Scientific Officer at Noisy Guts. Mary has a background in biology, with two degrees from the University of Cambridge and post-doctoral research experience. She spent several years undertaking research into the diagnosis of IBS and IBD. She was the winner of the 2018 CSIRO Breakout Female Scientist Award.