Are Coeliacs Skinny? What Is The Reason?

on September 29, 2022

Coeliac disease has become increasingly prevalent with the rate of diagnosis increasing significantly over last 20 years or so. And with the increase of the diagnosis of coeliac disease there has been a perception developing that all coeliacs skinny or underweight but is that really the case?

Generally, those people with coeliac disease are not necessarily underweight. A recent study by the National Library of medicine show that 54% of people diagnosed with coeliac disease were classified as having a normal weight, whereas 36% of people were found to be underweight and approximately 10% of people were classified as either overweight or obese.

Whereas a publication by the University of Chicago stated that the number pf overweight people was anywhere between 22 and 32%. The differences between the figures are fairly likely to be related to how people are classified but it is impossible to tell from the information provided from either source.

These studies suggest that while there is definitely bias towards normal weight or being underweight it is certainly not a precondition of having coeliac disease. Additionally, there was no significant difference between males and females within the studies nor was there any difference in the level of symptoms.

Why Are Coeliacs More Likely To Be Underweight?

Coeliacs are more likely to be underweight because of the nature of the disease and how it affects the body. Coeliac disease is essentially an inflammation of the villi in the small intestine. Villi are small structures which sit on the walls of the small intestine and help to increase the surface area of small intestine dramatically allowing food to be absorbed more readily into the bloodstream.

Villi do this by having pointy structures that stick out from the wall of the small intestine. This increases the surface area of the small intestine significantly. Somebody that has a gluten intolerance will have inflamed villi that lay down on the sides reducing the surface area. This therefore results in the body being less able to absorb nutrients into their bloodstream.

A dietitian that I visited described it as a normal person having surface area the size of a tennis court to absorb food whereas someone with coeliac disease has only an area the size of a table tennis table.

As a result of this coeliacs are less able to absorb nutrients and therefore much more likely to be underweight than overweight. A result of this is a very common symptom of coeliac disease is diarrhea.

Will Moving To A Gluten-Free Diet Help A Non-Coeliac Lose Weight?

There has been an increasing fad for the last 10 to 15 years to move to gluten-free diet even if you are not gluten intolerant or a coeliac on the basis that it is a healthy option and will help you lose weight.

This notion is a myth as gluten-free diets do contain as much or even more carbohydrates and sugar as conventional diets. This means that there is no benefit generally in moving to a gluten-free diet if you’re not coeliac. Generally it will not change your weight and will not provide any significant health benefits.

This of course assumes that you do not change any other lifestyle factors or rate of consumption of food generally.

Do Coeliacs Normally Put On Weight After They Switch To A Gluten-Free Diet?

People that have been diagnosed with coeliac disease generally put on weight in most cases with the University of Chicago newsletter stating that approximately 81% of people that switch to a gluten-free diet do gain weight in the first 12 months. This is obviously a desirable outcome for those people that are underweight already, however, it can be extremely problematic for those that were already in the overweight category.

The main reason why coeliacs gain weight is because the villi within the lower intestine repairs itself over time. This increases the ability of a coeliac to absorb food significantly resulting in an increased amount of nutrients reaching the bloodstream. This means that coeliacs that switch to a gluten-free diet and eat precisely the same amount of food will end up with a greater amount of nutrients in the bloodstream resulting in weight gain.

How Do Coeliacs Maintain Their Weight When They Switch To A Gluten-Free Diet?

For a coeliac to maintain their weight when they switch to a gluten-free diet is somewhat of a challenge for a couple of reasons. The first is that the amount of food you can get versus the amount of nutrients your body absorbs has changed which means that there needs to be some degree of adjustment with your intake of food in order to maintain the same weight. So they will need to be a period of adjustment when transitioning to a gluten-free diet.

Additionally, the effects of moving to a gluten-free diet In terms of your ability to absorb food is not immediate. So for the first couple of months that you’re on a good free diet your ability to absorb food will be changing.

The second challenge associated with maintaining weight is realistically assessing where you are in terms of being underweight, overweight or normal weight because obviously if you’re underweight already gaining weight is not a bad thing. However, many people find it difficult to accept this as the general perception is that any weight gain is bad.

However, if you wish to maintain your weight once you switch to a gluten-free diet it is important to reduce portion size, maintain an active lifestyle or increase the activity level in cases where you are already in the overweight or normal category and actively monitor your weight to ensure that you know whether you are going up or down.

However, it is important to note that daily monitoring of your weight is not a helpful thing as day-to-day fluctuations in the water content in your body and other factors will mean that it will go up and down a little bit. It is best to weigh yourself only once a week at the same time of the day, for most people the ideal time is in the morning.