Digestive system 101.

[InVivo]

So, lets talk about your gut.

If you have coeliac disease (and I’m guessing that most people reading this, with the exception of my family and friends, do), you will have at least a basic understanding of what happens to your gut when you eat gluten.

The thing about CD is, it’s quite individual. Some people have no symptoms at all until they’re diagnosed with gastrointestinal lymphoma, other’s have symptoms that are severe and cause them much suffering, but don’t involve the gut at all, eg migraines or dermatitis herpetiformis, fatigue, and for some people it’s all gut. Pain, constipation or diarrhoea, bloating and distension, heartburn et al.

Now, the ‘treatment’ for CD, is a lifelong gluten free diet. And many people, when they go GF, find that their symptoms disappear, and as long as they’re strict about adherence, they don’t have any more problems.

However, recent findings in the States stated that about 50% of coeliacs still have symptoms or problems, 5 years after diagnosis, even with careful adherence to the GF lifestyle.

So what’s that about??

Well, obviously, for some people there’s other stuff going on. It’s common to develop intolerances to other foods, or continue to feel tired all the time (even if it’s less than before), or be so bloated that you might be offered a seat on a crowded tube.

With this in mind, I’ve decided to write about the digestive system, and all the things that can go wrong as a consequence of coeliac disease, that are not necessarily rectified by just avoiding gluten.

This is no small undertaking, and to make it easier to digest (please excuse the terrible pun), I’m going to break it down into several posts.

This first one is going to read a bit like a biology lesson, but I think it’s important to know how your gut works, in order to understand what goes wrong.

I’m going to start at the very beginning, and talk about the basic, healthy functions of the whole digestive system.

Digestion actually starts in the brain. When you see, or smell food, or sometimes just think about it (as in, mmm, I’m going to get out of bed and raid the fridge for that left over dessert that I didn’t finish earlier), your brain sends messages to your digestive system to start preparing.

Then you put food in your mouth and chew it, which starts to break food down mechanically, and your mouth produces saliva.

Now, I doubt you’ve ever given much thought to saliva. To a geek like me though, it’s pretty interesting. Saliva contains some very clever chemicals, some of which start to digest carbohydrates and fats, some antibacterial agents and many other substances as well.

Then you swallow your food and it heads down your oesophagus into your stomach.

Your stomach contains gastric acid (aka stomach acid or hydrochloric acid), which starts to break down proteins in food, stimulates the secretion of other substances important for digesting foods efficiently and creates an environment so acidic that many micro-organisms can’t survive, which helps prevent infections.

Once food leaves the stomach, it arrives in the small intestine, which is the location of the root of all our problems in coeliac world.

The small intestine is where most chemical digestion takes place. Digestive enzymes are secreted by the pancreas and enter the small intestine from a small connecting tube called the pancreatic duct. At this spot, the gall bladder also releases bile from the liver. Bile is important for fat digestion.

It gets a little complicated here, but certain nutrients stimulate the small intestine to produce a hormone, which allows the enzymes secreted by the pancreas to enter the small intestine.

Now, digestive enzymes are very important. They break down foods into their smallest individual parts, so that these can be absorbed across the gut wall and into the body to be used for, well, everything.

The small intestine has villi, finger-like protuberances that I’m sure you’re all more that familiar with, and these villi have micro-villi, which are like microscopic hairs, and these microvilli also secrete enzymes that are responsible for the final stage of digestion.

After the small intestine, the mush that started off as your food passes into the large intestine (aka the colon or the large bowel).

The final stages of absorption happen in the bowel.

It is estimated that we have around 15,000 different species of bacteria (some say as many as 30,000) living in out gut, and the majority of them are found in our large intestine. You actually have more bacterial cells here, than you have human cells in your whole body (leading to some speculation about who’s the boss in this situation…….)

These bacteria have many functions, including digesting some foods that we cannot without their help and manufacturing some important vitamins, such as K (very important for bone health, as food sources alone are insufficient) and Biotin.

These bacteria are also incredibly important for the immune system, but more on that in a later post.

Water is absorbed out of the remains of the food here and stool is formed out of any undigested / unabsorbed food, fibre, bacteria and waste products from the body - toxins, spent hormones, old blood cells etc.

I’m sure I don’t need to go into detail about what happens last.

So, that’s a basic outline of what happens when things go as planned. Stay tuned for what happens, and why, when things go wrong…..

[Irene Administrator]

A handy post!

We know from our twitter and facebook page that lots of Coeliacs continue to suffer abdo problems or worse symptoms than pre GF. Often Drs are at a loss to explain why as their blood tests are spot on and they are on a strict GF diet. So we know your series of blog posts on this will be a really valuable insight into what other factors could be causing problems. We look forward to more inside info for Coeliacs in future.

[sandie]

You are such a star writer... top stuff...