Skip to 0 minutes and 15 secondsMy name is Glenn Gibson and I am a microbiologist. And I'm a member of the Food and Nutritional Sciences Department here at the University of Reading. And we're in one of the labs at the University, which has lots of gut models in it. And what these do is simulate the digestive system, so they're full of microorganisms, and we test foods in these models. We might make a model that is reflective of the infant, or teenagers, or adults, or elderly people, or people who have particular clinical states linked into their gut. And actually, this particular model is being used by two researchers called Holly and Brody.
Skip to 0 minutes and 55 secondsAnd the model actually simulates the diet that we think may have been intaken by Henry VIII. So this is Henry VIII's gut model, if you like. So this is my research project on Henry VIII and his gut health. And how it affected him in his later life, with his leg ulcerations and his high protein diet. So one of the challenges we found was how to find the proper digestibility for this high protein diet. Because if we eat small protein, the digestibility could be lower. So these are the samples from the gut model. These three are the samples from the normal diet, and this is the samples from the high protein diet.
Skip to 1 minute and 39 secondsYou can see through the vials, it's much darker here in the high protein diet. It's quite likely that Henry might have had a vitamin C deficiency, as we think he's having this high protein diet and not consuming that much fruit. And any fruit he would've consumed would likely have been cooked. And vitamin C is a water soluble vitamin, so when it's cooked, it's just destroyed. The theory is that in Henry's gut, he's got too many of these bacteroides. When they're in the gut, they're beneficial to the hosts. But when there's too many of them, they can leave the gut, like through a rupture, and travel in the blood to other places in the body and cause abscesses.
Skip to 2 minutes and 18 secondsSo Henry had these leg abscesses. So we think the bacteroides. May have travelled and caused these leg abscesses. Nowadays in the UK, people are consuming 75 grams of protein per day, average. So we are having a high protein diet, even though compared to what we think is King Henry VIII's diet, which is 226 grams per day of protein. It's still lower, but it's already relatively high.
How healthy was Henry's diet?
In this video, Professor Glenn Gibson, from the University of Reading introduces the artificial gut model, that two of his students, Brodie and Holly have created to simulate Henry VIII’s digestive system.
The artificial gut models in Glenn’s lab are packed full of live bacteria from the human gut. Some of these bacteria are beneficial for health, some have a neutral impact and others are pathogenic (cause disease). Maintaining balanced populations of these micro organisms in the live, human gut is essential for our digestive health and the nutrients we consume play a key role in this. The artificial gut models provide an ideal opportunity for researchers to manipulate nutrients, under lab conditions, to see what impact this has on the balance of microbiota (all of the bacteria) within the human gut.
Brodie set out to investigate Henry’s diet and the impact this had on his health for her her final year research project. As you’ve discovered in previous Steps, we don’t know for certain what Henry ate but for the purpose of this experiment, Brodie worked on the assumption that he consumed a vast amount of meat.
To test Henry’s diet Holly introduced a liquid medium, consisting of concentrated bovine protein, into the artificial gut model, equivalent to the high protein meals we think Henry enjoyed. But just how protein-rich would this meal have been?
The UK Department of Health’s Dietary Reference Value (DRF) recommends that we consume 55g of protein per day. In reality we tend to consume significantly more; 75g of protein per day, with 2.5 % of the population consuming up to 120g. The average, worldwide protein consumption per day is 100g. Brodie’s research suggests that Henry may have enjoyed as much as 226 g of protein per day – a wapping, 4 times our current recommended daily allowance!
The team knew that a high protein diet encourages the growth of negative bacteria. Holly and Brodie fed their Henry’s artificial gut with it’s high meat protein diet every day for 4 weeks to allow it to stabilise; when they returned to analyse the ‘waste’ (stool) in his ‘colon’ at the end of the process, they expected to see increased levels of these pathogens.
Their predictions proved correct. They found a huge increase in pathogenic, Bacteroides and sulphur-reducing bacteria in samples gathered from all three sections of the ‘colon’ within the artificial gut. They also found a significant. reduction in the number of Feacalibacterium in the same samples.
The graph below records the number of Bacteroides, Feacalibacterium and sulphur-reducing bacteria Holly found in samples taken from three areas of Henry’s ‘colon’ in the artificial gut: the proximal, transverse and distal colon.
The first three bars within each chart represent what we assume was the less protein rich diet of the Tudor Commoners, whilst the second three bars represent Henry’s high protein diet.
Colon image adapted from ‘Wikimedia Commons website’ by Olek Remesz, 2007, https://commons.wikimedia.org/wiki/File:Colon_scheme.svg
What do these results tell us about the Tudor King’s health? These pathogenic bacteria produce a cocktail of hydrogen sulphide (a gas with the distinctive smell of rotten eggs!), p-cresol, phenolic and indolic compounds that promote cancer (co-carcinogens). These high levels of harmful metabolites would have been bad news for both Henry’s colon and his general well-being. The reduction in Feacalibacterium would have also been detrimental. They produce butyrate, a metabolite with many associated health benefits so a reduced number of these ‘good’ bacteria would have been less healthy for the King.
This is the first time Glenn’s lab have used their artificial gut models to simulate history, although they once analysed coprolites (fossilised human fecal remains) to try and identify the bacteria present in the gut of our ancient ancestors!
More generally, Glenn’s research team use artificial gut models to simulate the gut of a wide range of age groups and conditions; from infants to the elderly and clinical states such as bowel cancer and Inflammatory Bowel Disease (IBD). They investigate how they might help improve the digestive and overall health of these various groups, through dietary change.
Holly, for example, is currently investigating the effect of probiotic supplements (healthy carbohydrates) protein metabolism. Using the gut model, she has found a positive impact that suggests the probiotic supplements help reduce the number of harmful Bacteroids normally associated with the high protein diet we enjoy today. Her next step is to set up a human trial to test this further.
If you’d like to find out more, you may like to visit The International Scientific Association for Probiotics and Prebiotics ISAPP.