Amanda Watts peers into your guts to see what’s happening to your FODMAPs

WORDS: Amanda Watts, IMAGE: Simon Madden

You can’t swing a chalk bag these days without hitting someone suffering with IBS (Irritable Bowel Syndrome). Bloating, gas, distension, abdominal discomfort and – weirdly – either diarrhoea or constipation (or even more weirdly a mix of both) are not the most fun reactions to have to food. I’m sure you can imagine how problematic tummy pain, bloating and lots of wind are to a day of crushing. IBS symptoms can be super stressful and anxiety inducing for any climber. They can also interfere with training and can compromise your climbing performance. As a result, I have seen many athletes desperately guessing and eliminating foods that they suspect may be the cause of their symptoms. Usually I get to see them once they are on a self-imposed diet of lettuce and potato and yet are still suffering. So, what is potentially causing these symptoms? And is the lettuce-only diet the answer?

Regarding the lettuce, the answer is definitely no. Coffee, fat and gluten are often blamed for the IBS symptoms, but there has never been much proof that these are the true culprits. Thankfully, there has now been a lot of research into why some people develop these symptoms. For some people, the culprits are carbohydrates called FODMAPS.

Don’t check yo’self lest you wreck yo’self. Going all-lettuce is not going to save your guts and is sure is hell aint gonna make you climb no better. Image Simon Madden

Don’t check yo’self lest you wreck yo’self. Going all-lettuce is not going to save your guts and is sure is hell aint gonna make you climb no better. Image Simon Madden

FODMAPS stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides And Polyols. These are poorly absorbed, short chain, rapidly-fermentable carbohydrates or sugars. The names sound complicated, but they are just the scientific names for the structure of each sugar molecule. FODMAPs are found in heaps of foods such as fruits, vegetables, grains, legumes, dairy, nuts and seeds, which is partly why it is so tricky for people to identify which foods are actually causing their symptoms without the help of an expert.

To appreciate how FODMAPs can be triggers for IBS, it is important to understand how food is digested and absorbed in the body. Our gut (including our small and large intestine) has the important function of digesting and absorbing the nutrients in our food. It therefore, has a major role in keeping us healthy. Food passes from our stomach into our small intestine, where most of it is broken down into small molecules and absorbed into our bloodstream. From the small intestine, undigested food continues to our large intestine where water is absorbed to help prepare the food to leave our bodies. Short chain fatty acids are produced and the bacteria that happily live in our large intestine ferment this food, producing gas. This process is normal, is experienced by everyone and is important for a healthy gut. Where IBS kicks in, is the symptoms that occur when FODMAP foods are consumed.

Let’s look at when lactose (the carbohydrate part of milk) is malabsorbed as an example. Lactose is a disaccharide, so picture two sugar molecules stuck together. To be absorbed from our small intestine into the bloodstream, the lactose molecule needs to be split into single molecules by an enzyme called lactase. Lactase is found in the wall of our small intestine and the amount we have varies from person to person and is influenced by your ethnicity and the health of your gut. If you don’t have enough lactase, then you won’t be able to absorb all the lactose you consume. This leaves extra lactose floating around that will continue on to your large intestine. In the large intestine, the bacteria that live there ferment the lactose and produce fatty acids and gas that can cause bloating, pain and an upset stomach. Pretty unideal symptoms mid training session or halfway up a cliff.

Other examples of FODMAPS are:

  • Fructose in excess of glucose – found in some vegetables, some fruits and honey
  • Sorbitol – found in some fruits and some artificial sweeteners
  • Mannitol – found in some vegetables and some fruits   
  • Fructans – found in wheat, rye, onions and garlic
  • Galacto-oligosaccharides (GOS) – found in legumes

So, in everybody, FODMAPs are not completely absorbed. However, for people with IBS, some or all FODMAPs can cause symptoms. It is thought that in IBS, there may be a larger than normal amount of gas produced or the gut is more sensitive to the gas. Additionally, a possible cause is something called ‘small intestinal bacterial overgrowth’ (where the bacteria from the large intestine have moved up into the small intestine). Often people with IBS can eat just a small portion of a FODMAP food before they have symptoms. Some people experience these symptoms to the extreme, while others may just find them mildly irritating.

The trick is to work out if it is FODMAPs causing symptoms and, if so, which ones and how much. This can be done by following a short term (two to six week) low FODMAP diet, with a series of food challenges that begin once your symptoms have resolved or significantly improved. Make sure you have this process overseen by an accredited Sports Dietitian or dietitian with experience in low-FODMAP dietary management.

The cheat notes:

  • There are a bunch of diseases that can stop our gut from functioning properly e.g. coeliac disease, Crohn’s disease and ulcerative colitis and bowel cancer, and it’s important to exclude all the other disorders before confirming it is actually IBS.
  • Stop trying to guess which food has caused your symptoms. There’s a good chance it wasn’t what you thought it was. It may have been the pear on the pear and blue cheese pizza, not the base.
  • The low FODMAP diet is short-term. It’s important to get help excluding, challenging with and reintroducing FODMAPs into your diet, to make sure you are getting everything you need to be healthy and crush your projects.  

Following a low-FODMAP diet can be tricky for anyone. For climbers, travelling, spending days on the cliff or hunting for boulders, it can be even harder. Eliminating foods from your diet needs to be done carefully and in a calculated way to make sure your energy and nutrient needs are met. A low-FODMAP diet for an athlete should be overseen by a dietitian experienced in sports and FODMAPs to make sure your training and days at the cliff aren’t compromised.

Sponsored by Evolv, Black Diamond and Beal, Amanda Watts is an Accredited Practicing Dietitian, Accredited Nutritionist and SDA Sports Dietitian at Thrive.

This piece originally appeared in Vertical Life issue 23Download the full issue for free here.

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