Summary: Some of you guys take cocaine and won’t eat Gluten but that’s none of my business. I’m just shouting my message for the common good. Eat a normal, balanced diet and you’ll be fine – unless you’re a Coeliac. You guys just keep doing what you do.
Rise of the gluten free diet – for better, or for worse?
In 2013, the NPD reported that around a third of adults in the US want to cut down, or completely remove the protein Gluten from their diets1. This trend has extended to the UK, where I believe at least everyone knows someone on ‘the gluten war’. The rising belief that gluten is bad for you has stimulated a dramatic increase in the Gluten-free food market, with more and more companies becoming involved in the latest diet fad. While it is true that for a certain group of people, suffering from Coeliac Disease, gluten is indeed very bad and can have a very negative effect on their health and wellbeing. However whether or not people who don’t suffer from the disease will benefit from the Gluten free diet remains to be seen.
With the increased interest in Gluten, and its effect on public health, a number of studies have been done investigating the associations between gluten and numerous diseases. In April 2017, a prospective cohort study was released examining the association between a long term intake of gluten and incidence of coronary heart disease2.
This study conducted a long term dietary analysis of a very large sample between 1986 to 2012 (or time of death/cardiovascular disease incident). The cohort was split into five subgroups, based on fifths of average gluten intake. For the study they then compared the incidence of cardiovascular disease between the highest fifth and lowest fifth group. For reference, in the highest group the average gluten consumption per day was 10.0g for men, and 7.5g for women. In the lowest group, it was 3.3g for men and 2.6g for women. They discovered that the group who consumed the lowest amount of gluten had an incidence rate of cardiovascular disease of 352 per 100,000 person years, which is actually higher than the 277 per 100,000 person years incidence rate of the fifth who consumed the highest amount of gluten. This may seem like an interesting finding however numerous complex statistical tests demonstrated that the increases in results were insignificant, meaning that they actually mean very little in a real world setting. However it does show that there is no evidence that a gluten free diet decreases risk of cardiovascular disease, as is a commonly peddled message by many gluten free advocates.
A possible reason for the slight increase in CVD in low gluten-eaters is the fact that people who religiously avoid gluten tend to have a decreased consumption of whole grains. Whole grains as a food group have been repeatedly shown to decrease risk of cardiovascular disease, so decreasing whole grain consumption could result in an increased risk of developing CVD3.
On the other hand, similar studies have shown that a gluten free diet can be an effective tool for weight-loss, which in itself has cardiovascular benefits4. This considered it is safe to say that the studies so far released are simply pieces of a jigsaw puzzle, revealing details but not the overall picture. In individuals with a healthy weight, there seems to be little benefit to undertaking a gluten free diet, and restricting the consumption of whole grains cannot be deemed a healthy plan. More studies are needed to determine the long term causal relationship between gluten free diets and overall health, not just cardiovascular disease, but for now it has been shown that completely removing gluten from your diet may not be the healthy path it seems, and eating a balanced and varied diet could instead be a better option.
NPD. (2013). Percentage of U.S. Adults Trying to Cut Down or Avoid Gluten in Their Diets Reaches New High in 2013, Reports NPD. Chicago.
Emilsson, L. & Semrad, C.E. Dig Dis Sci (2017). doi:10.1007/s10620-017-4649-0