The dos and don’ts of eating vegetables when you have IBS

For some, eating too much of their greens is simply not the recipe for good health. Photo / Getty Images

A diet of pure artichoke is never going to be a winning formula for you or your bed partner, but for those who suffer from irritable bowel syndrome (IBS) – a nasty bout of cramps, diarrhoea, bloating or constipation – some vegetables could be making their suffering worse.

“You may find that eating a particular type of vegetable sets you off,” says Bridget Benelam, a nutrition scientist from the British Nutrition Foundation.

The cause of many undesirable emissions stems from the brassica family.

Chicory, for example, contains inulin, a type of fibre also found in Jerusalem artichokes that is fermented in the gut and is responsible for people getting wind after eating them.

Cruciferous vegetables, such as cauliflower, cabbage and broccoli, can sometimes be the culprit, as can lentils, beans or pulses.

Some so-called “nightshade vegetables”, including aubergine and peppers, have also been linked with problems of inflammation because they contain bitter-tasting alkaloids, chemicals that occur naturally in the plant to protect it from pests.

“In general, vegetables are anti-inflammatory,” says dietitian Linia Patel of the British Dietetic Association. “But there is anecdotal evidence that the alkaloids in nightshade vegetables – of which the biggest one is solanine – in high quantities causes inflammation.” To counter this, she advises speaking to a dietitian and “doing a proper elimination diet” if they are aggravating an irritable bowel.

The “fodmap” diet (which stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols – all short-chain carbohydrates) is recommended for those suffering with the dreaded IBS. It aims to minimise the type of fermentable carbohydrates that are causing the problems in the gut in the first place.

Foods that are found to have an irritating effect on the gut – high fodmap foods such as artichokes, onions and garlic – are removed before being slowly reintroduced to uncover the specific triggers. Low fodmap options include grains, oats and courgette.

Raw versus cooked

Boiling vegetables into mush “a la Granny” will not win any awards for flavour or health, but if you’re suffering from gut problems, cooked vegetables are easier to digest. However, if you’re trying to garner the benefits of your veggies’ nutrients, the gold-star method is to keep them al dente or to consume raw, if palatable. “Steaming keeps the highest level of nutrients, with microwaving coming a close second,” says Patel. The longer you boil, the more nutrients you lose, with water-soluble vitamins such as C or B leaching into the water.

The best way to get the nutrients out of most vegetables is to keep them al dente or to consume raw. Photo / Getty Images

Not all vegetables are best eaten raw, however. The humble tomato (strictly a fruit) contains high levels of lycopene – an antioxidant believed to have benefits ranging from aiding heart health to protection against certain types of cancers – which is more easily absorbed if cooked.

To get even more health bang for your buck, add olive oil to vegetables that contain beta-carotene, such as carrots, to increase the amount the body absorbs. “Vitamin A is a type of beta-carotene, which supports healthy immunity and skin, and is good for our eyes,” says Patel. She recommends sautéing with olive oil or adding the oil after steaming.

You might want to rethink your blender addiction, too. “When you blend, you’re breaking down the structure of the fruit or vegetable – particularly when it comes to smoothies and juices,” says Benelam. “The sugars are classified as ‘free sugars’ because they are no longer bound up in the structure of the fruit or vegetable, so they are classed in the same way as ‘added sugar’ because the body can absorb it much more quickly.” It doesn’t mean you should be cutting out purees, juice or smoothies completely, but Benelam says it is better to consume most of your vegetables whole.

A vegetable or fruit smoothie is only counted as one of your recommended five a day.

Too many fruit smoothies could affect blood sugar levels. Photo / Getty Images

“You won’t lose nutrients; it’s more of an issue with fruits as they tend to be higher in sugar, so it could affect blood sugar levels,” says Benelam. “Plus you would consume a lot more fruit and sugars if blended.”

Using a juicer, which separates out the fibre (the pulp and skin), can also extract some of the goodness, according to Benelam. When you’re not keeping the fibre, you are arguably just consuming the sugar. “You won’t be getting as much fibre as you would with eating the whole vegetable,” she says.

More reasons to be wary of veg

If you are taking an anticoagulant, such as warfarin – prescribed for those at increased risk of developing harmful blood clots – some vegetables can affect how it works. These include green leafy vegetables that contain vitamin K, such as broccoli, spinach and lettuce. “The advice is, rather than cut these foods out, you should keep your intake of them fairly constant so that the amount of vitamin K in your blood stays stable,” says Benelam.

“People with kidney conditions may need to control their potassium intake and avoid certain types of vegetables that are high in it,” she adds. “This includes artichokes, beetroot, pak choi and raw spinach.”

For some, eating too much of their greens is simply not the recipe for good health.