Fermentation, gut Instinct and the brain

As a result of one of Mike's health issues, I've suddenly had to become an expert on all things to do with the digestive system. This has meant hours searching online for information, reading countless books, joining groups on Facebook and speaking with anyone and everyone who might have a clue how things could be improved.

My studies have lead me in many different directions but the two things that are most exciting and promising are fermented foods and the link between the stomach and the brain (yes, really!). So that's how I found myself at a Fermented Foods Workshop with the lovely Olivia at The Hive in Hove one Saturday morning a while ago.

I'd been warned that parking is both difficult and a bit expensive in that area and so I left extra time to find a good parking space. I was lucky in that I managed to find one just around the corner with plenty of time to spare and so I had a little wander around the area and found a small park to explore behind the venue.

 

The little cafe backed onto the park and I loved this artwork!

There were 12 of us in the group and we learnt how to make Sauerkraut, Kimchi, Kefir (milk, water and coconut), Probiotic ginger beer, Kombucha and Matsoni yoghurt.

We each had small plastic cups in which to taste the various ferments Olivia had brought and the first thing we tried was the sauerkraut. It was completely different from the shop-bought stuff which is usually pasteurised which of course kills off all the good bacteria.

Then we had a go at making it ourselves! We'd been told to wash our hands upon arrival and we soon discovered why. We were given half a cabbage chopped into pieces in a bowl, with the outer leaves removed. Then we added a teaspoon of Himalayan pink salt and the fun began - we had to massage the cabbage to break down the cell structure and release its juice to form a brine in which it would ferment. It was hard work but I was amazed at how much juice came out.

Once it was swimming in juice we packed it tightly into a small kilner jar (the sort with the clips and a rubber seal used for preserving/bottling) and placed one of the tough outer leaves from the cabbage on top of the mixture to keep it all submerged under the brine.

My first ever sauerkraut.

I tasted it each week and it was fascinating how the flavour developed. I found that it seemed just right for our taste after 4 weeks of fermentation and it really didn't last long at all before I had to make another batch.

This is a version Olivia had made to which she'd added some grated carrot & mustard seeds

Olivia in full flow together with her very active ginger beer!

She recommended several books we might find useful and I've already finished 2 of them. I keep going back to Gut by Giulia Enders as it has so much fascinating information and is both funny and informative.

It was the description on the back cover which got me intrigued:

From our miraculous gut bacteria - which can play a part in obesity, allergies, depression, and even Alzheimer's - to the best position to poo, this entertaining and informative health handbook shows that we can all benefit from getting to know the wondrous world of our inner workings.

I'll come back to that a bit later......

We didn't need to take notes as she gave us a leaflet to take home which had all the recipes we needed to get started. Having made our own sauerkraut we then tasted all the other interesting things Olivia had brought.

Next was Kimchi (a Korean vegetable fermented dish with cabbage, daikon (a long white radish-type vegetable), garlic and ginger with a shrimp paste (which of course I don't use as I'm vegetarian) as a base but you can add all sorts of other things. It's very spicy and tasty.

Here's my own version which is bubbling away in the kitchen at the moment

I added turmeric to my mix but stupidly didn't wear plastic gloves when mixing!

We tasted several different concoctions made using water kefir grains and we were given some to take home but they didn't really appeal so I haven't continued using them. I do use the milk kefir grains though. When I first got them there were 5 grains the size of a pinhead. Now they've produced a huge colony which look a bit like a cross between cauliflower florets and cottage cheese:

You simply put the grains into milk, leave it for about 24 hours, then strain the liquid off, leave it for another 24 hours then enjoy. It's like a slightly tangy yoghurt. I mix wheatgerm and or ground flax into it and we drink it each day.

Then came something called Komboucha which is made using a 'scoby' (Symbiotic Culture Of Bacteria and Yeast) which is added to sweet black tea to create a slightly tangy drink which is supposedly good for your digestion.

When Olivia passed it to me she said my reaction was brilliant 'cos I just said "Yuk, it looks like a breast implant!" The resultant drink tasted OK but I still haven't tried making my own.

Bleurgh! Not the most attractive looking thing is it.

I tried the matsoni yoghurt and whilst it tasted OK I haven't bothered to try making it. I did however leave the workshop feeling confident and excited to explore the world of fermentation further. Here's some fermented tomato ketchup I'm experimenting with at the moment using home grown tomatoes. It's very lively now so I've put it in a bowl to catch any escaping liquid. You can actually see some bubbles in the photo.

Now, back to the comments about the association between our gut and the brain. This is a very new  and fascinating kind of research and I've been reading as much as I can about it. The Clever Guts Diet by Michael Mosley was excellent - did you know that buried deep in our intestines is a very thin layer of brain? Me neither! 

That's what really peaked my interest and prompted me to search for any research on the connection. Low and behold this article appeared in Science Daily which suggested that intestinal bacteria may accelerate the development of Alzheimer's. I was straight onto messenger to ask my favourite young scientist, Lizzie Glennon (who's appeared on my blog many times before), what she thought about it. I know she won't mind me sharing her reply:

I think it is a super interesting paper - basically they look at a mouse model of AD, and find that the mice with the AD gene have different bacteria in their gut, and they find that when they raise these mice so they do not have bacteria in their gut they have less Abeta and less inflamation in their brains. To me this is not overly suprising - there is a lot of reserach on what is called the gut-brain axis, showing how the microbial communities in the gut can effect the brain. Also gut bacteria have been link to Parkinsons disease so it is not a surprise that gut bacteria are link to AD. Its hard to interpret what their finding could mean for AD - they are in many ways quite preliminary as they just show that there are changes in the gut bacteria and there are also changes in amyloid beta in the brain (though they do show this very well and convincingly). What is missing is any behavioural data - they don't show if there are any changes in the mouses memory for example. It is also hard to interpret what this actually means (and this is just a fact of life - we don't have the research yet, not a criticism of the paper). I'm not sure anybody can categorically classify different types of gut bacteria as "good" or "bad" (obvs unless they cause actual disease!!!), or as "causing inflammation" and "preventing inflammation". I'm not sure whether people are even agreed on whether it is good to have lots of different bacteria or mostly the same type of bacteria. (I could be wrong about this as i am not a gut bacteria scientist!) Another thing is that obvs this work is done in an AD mouse model, and literally every drug which has worked in AD mouse models has failed in people. So its not clear what the limits of the AD mouse model are - how accurately do these mice reflect disease development and progression. However all that said i think it is a super interesting paper, and i hope some more work follows it up!!

Yay, exciting indeed and she is currently proposing to investigate something similar.

I also asked Laura Phipps from Alzheimer's Research UK for her views and was delighted to learn that they are funding research at King's College.

It's interesting and an area that we're funding research into as well. There has been growing discussion, as I'm sure you know about the role of the immune system in the development of Alzheimer's and whether other infections or alterations in the microbiome of the body could swing balances in other areas of health, even brain health. This study is in mice, so we need to take that into account.

We're funding a study at King's looking at stool samples to understand more about this in people. I guess the important thing to understand from this research is what practical implications it could have. We need gut bacteria and so while it's important to understand how our gut microbiome could affect diseases like Alzheimer's and crucially, why, it isn't something that is too easily changed. I;m not an expert on the make-up of gut bacteria but I image it could also be influenced by diet - which we know can also influence risk of diseases like Alzheimer's - so unpicking the causal link could be hard.

A very interesting area of research though and just shows how connected the brain is to everything else happening in our body. I think many people think of it as very separate, but we know that lots of things that happen in our body have knock-on effects on our brains too.

I completed marathon number 122 yesterday which means I've still got 5 to document.........