Beans, lentils, oh my! How to take the gassy side effects out of vegan food

We asked three dietary experts for advice

25 July 2019 - 08:58
By Sanet Oberholzer
Beans, beans, the magical fruit ...
Image: 123RF/Avemario Beans, beans, the magical fruit ...

The vegan trend just seems to keep growing as more people explore ways to cook meatless meals. Often this means experimenting with other sources of protein, and legumes are a popular choice in this regard.

Legumes such as lentils, beans and chickpeas are versatile, delicious and nutritious, but they're also notorious for causing flatulence and bloating in some people.

We asked three experts how to reduce these gassy side effects. Here's what they had to say:


Registered dietitian and spokesperson for the Association for Dietetics in SA

Although bloating can be very uncomfortable (not to mention the farts), there is no other physical harm caused by eating beans, so do not allow a little gas to stop you from enjoying the amazing health benefits of eating them.

Try these tips:

  1. Add seasonings such as bay leaves, onion, garlic and/or pepper corns when cooking, but leave salt and acidic ingredients (tomatoes, lemon juice and vinegar) until after cooking as they can harden beans (and increase bloating and cramps). Add herbs and spices near the end of the cooking process.
  2. Try to eat beans and similar legumes regularly to build up your body's ability to process them, but limit the quantity of beans you initially consume per meal. Start with small quantities, then slowly increase consumption levels as your digestive tract adapts to digesting the beans.
  3. Chew each spoon of beans thoroughly. If you eat too quickly, you won’t chew enough and will be more likely to swallow air, further increasing any issues with gas. Avoid carbonated drinks and chewing gum as they also increase gas. Drink more water than usual — this will help the digestive enzymes process the food better.


Registered dietitian

Legumes can cause farting because of certain molecules they contain and our inability to break those molecules down. To assist with this:

  1. Start slowly: If you go from eating no beans to two cups a day, your body may not be able to handle all of those oligosaccharides [a type of carbohydrates found in beans] and, in many cases, they're only partially digested in the human gut.
  2. Soak, rinse and cook: Soaking raw beans overnight helps to reduce the oligosaccharide content — as does cooking. When buying precooked, tinned beans, make sure to rinse them thoroughly. The cloudy ‘juice’ they are tinned in is full of the galacto-oligosaccharides we battle to break down.
  3. Take a good quality probiotic: It is really important to make sure your gut is being looked after.
  4. Seek advice: A well-versed dietitian can offer a plethora more advice on the topic of gut health and vegan eating.


Registered dietitian and spokesperson for the Association for Dietetics in South Africa 

  1. Introduce legumes in your diet gradually to allow your digestive system time to adjust to the increase in fibre. 
  2. It has been suggested that pre-soaking beans, and discarding the soaking water before use, makes them easier to digest. Similarly when using canned beans, rinse them and discard the water before use.
  3. Some beans are reported to be better tolerated than others in regards to side effects, so try a variety to see which ones your body tolerates better. 
  4. Those who really suffer from gassy symptoms after eating legumes can use a digestive enzyme supplement.  A supplement containing alpha-galactosidase will help with reducing the production of gases in the colon as the carbohydrates the beans contain ferment.