You know that constipation is the classic consequence of not eating enough fibre. But adequate fiber intake also plays a role in everything from helping you manage your weight to lowering your risk for heart disease, diabetes, and even some cancers.

Here, 5 signs to watch for:

Your poo is the wrong shape
If your bowel movements are small or hard, like pebbles, that's a sure sign you're falling short, says Dr Robynne Chutkan, author of The Bloat Cure. "A C-shape or a straight log is ideal," she says. 

You're hungry after a meal
Fibre takes up lots of space in your digestive tract, which is one of the reasons why it helps you stay satisfied longer. So if your stomach starts rumbling within an hour or two after eating, that's a sign that you probably didn't get enough fibre in your meal, says Frances Largeman-Roth, author of Eating in Color.

Next time, try starting off with a small side salad or a small bowl of vegetable-bean soup. (Or if you're having a salad for your meal, add in ¼ to ½ cup of cooked beans.) All are easy ways to up your meal's fibre content and help you feel fuller, she says. 

You're bloated
It's no secret that overdoing it on the roughage—especially if you aren't used to it—can leave you feeling bloated and uncomfortable. But eat too little fibre, and you're stuck with the same problem. That's because fibre keeps everything in your pipes moving at a smooth, steady pace. "Without enough fibre, the products of digestion often get stuck along the digestive superhighway, leading to backups and bloat," Chutkan says. 

You need a post-meal nap
You already know that eating a ginormous meal can make you sleepy. But if you regularly find yourself crashing after you eat, a lack of fibre could be to blame, too. Fibre plays an essential role in helping your blood sugar levels stay stable. But when you eat a low- or no-fibre meal, your blood sugar will spike more quickly—and soon come tumbling down. And that crash can leave you feeling sluggish or fatigued, Largeman-Roth says. 

You fail this gross test
Try swallowing a forkful of corn kernels without chewing them and seeing how long it takes for them to come out the, uh, other side, recommends Chutkan.That will give you a good idea of whether food is passing through your digestive system at a healthy rate—and whether you're getting enough fibre. If you spot the kernels in your stool within 18 hours, you're good. If it takes longer than that, you probably need more fibre. 

© Prevention Australia