The Gut: More Than Just a Food Processor
The gut is essentially the musculature that pushes food through our bodies. Along the way, food is broken down and processed into constituent parts such as amino acids and vitamins, which head out through the liver into the bloodstream to help keep all our metabolic processes, including building muscle, functioning.
Over the past 15 years, however, there's been this growing understanding (and new respect for) the gut, with some referring to it as the "second brain" of the body.
It turns out the gut is wrapped with more nerves than any other part of the body. This gut-based nervous system – the enteric nervous system – manages all the complex processes of digestion, including firing up all the hormones that need to turn on to manage everything from inflammation to stress to recovery.
Happy Gut, Happy Life
The gut actually initiates conversations with the brain about how it's doing, and the brain in turn has deep empathy with the gut. In other words, the gut is telling the brain about the kind of day we're going to have, not the other way around.
Want a happy day? Have a happy gut. Want to train like a fiend and have that training be effective? Have a happy gut. Want to have a happy gut? Eat sauerkraut.
We've all heard about probiotics and the "friendly bacteria" that live in our gut and their role in digestion. Most of us may not know exactly what that role is, but we keep hearing that digestion is better with good bacteria.
By good digestion, we usually mean that we can get the nutrients out of food that we need and eliminate the remainder that we can't use, like insoluble fiber. If we don't have healthy gut bacteria, the stuff we can't digest can stick around, fester, and cause irritable bowel syndrome and a host of other nasties like ulcerative colitis. Sauerkraut can go a long way in ensuring that you've got good digestion.
Sauerkraut, Not Drugs
There hasn't been a lot of research yet on athletic performance and gut microbiota specifically. Heck, research is still trying to figure out both what and how this symbiotic relationship between us and the bacteria that surround us (the microbiome), inside and out, works.
The one study done with athletes shows that elite rugby players have better gut bacteria diversity than non-athletes. There seems to be a connection between both exercise and protein there, but that's correlation, not causation.
There's a growing body of potential causation work around the microbiota, however, and its relationship to processes from obesity, depression, breast cancer, and even infant mortality. To make a long story short, a crappy state of gut means a crappy state of us. The less diverse the gut microbiota (for example, from only eating a lot of fast food), the more easily it seems we enter a broken or diseased state.
The great news is that rat models and increasing numbers of human trials are showing that as we start to improve gut microbiota, we see turnarounds in these neuro-physiological states. (My own group is looking at the relationship between gut state, brain state, and neurological conditions like autism.)
While it's still in the early days, it pretty safe to suggest that if training is flat, if stress seems high, if irritability seems higher than usual, and all other things are normal, it may be time to think about the state of our cohabiters, our gut bacteria. It may also be that by seeking to improve the state of our gut microorganism health through bacteria-rich foods like sauerkraut, our training and its effects improve – without changing anything else.
Feed Them Critters!
The best way to improve gut state so far is with real food, and especially bacteria-carrying food like sauerkraut. There's a double reason for that: sauerkraut is a bacteria carrier and a bacteria feeder.
When we use the term "carrier" we're talking about fermented foods. Fermentation is truly food processing via living organisms. Bacteria are introduced to raw food and they change it, while various bacteria grow along with it as it ferments. Sauerkraut is one of these fermented foods, so sauerkraut carries these super helpful bacteria to our guts.
When we use the term "feeder" we mean that sauerkraut itself provides the kind of materials these critters need to thrive. In other words, some probiotics are also their own prebiotics. Think of probiotics as the plants and prebiotics as the plant food. Sauerkraut has both the bacteria and the fibers these things love to chow down on.
Consider, too, that cabbage itself is a nutritional warrior. It's high in antioxidants, cancer-fighting compounds, fiber, vitamins (especially C), calcium, minerals, and even protein. It's also a libido enhancer.
Fermentation amps up all of its disease-fighting properties from antioxidants to its glucosinolates and isothiocyanates that, at least in lab studies, prevent cancer growth. Fermentation makes this superfood a super-superfood.
Make It At Home
Sauerkraut is a great way to start getting into fermenting foods, especially when you consider that getting non-pasteurized versions of sauerkraut can be costly and a pain in the neck.
The buck-fifty jar of sauerkraut on the grocery shelf? It's pasteurized. That means the bacteria are dead. If it's not pasteurized, your local health food shop is going to charge you 7 dollars a jar for cabbage that costs 70 cents. That's just not right. But making sauerkraut is dead easy. It takes 15 minutes and it has only two ingredients – cabbage and salt.
- Finely cut up cabbage. Use your favorite chef's knife or a mandolin to save time and get uber-fine slaw. The finer the slaw, the more the cabbage breaks down.
- Add 15-17g of salt (a rounded tablespoon) per 1000 grams of cabbage. That's 2.2 pounds of cabbage, usually an average-sized head. It's really important to get the amount of salt right, so measure it. Too much salt and you'll actually kill the bacteria before it starts; too little and you'll get nastiness – not the bacteria you're looking for.
- Work on your grip strength by tossing and squishing the salted cabbage for about 10 minutes. You'll know when you're there because water will start leaching out.
- Pack the cabbage into something like a mason jar or food-grade plastic container.
Warning: The only tricky bit here is to make sure you keep all the sauerkraut under the brine. Hold back a big leaf from the cabbage and once the mason jar is packed, layer the leaf on top. Use some of the cabbage core to act as a press between the lid of the jar and the cabbage.
Pressure is not what you're after here. You just need to make sure the cabbage is covered with brine so that it isn't exposed to air. Fermentation is anaerobic, without air. If you're using a mason jar, screw on the lid but keep it loose, not tight. That jar is going to start producing CO2 so a loose lid lets that gas escape.
You'll know you're on the mark if the brine goes a milky color and bubbles form at the top of the brine line. That's all excellent. Anything else is probably not. Again, you don't need a tight lid at all. As long as the sauerkraut is under the brine, you're good. As the CO2 rises, it will also push oxygen out of the jar (if it's a loose-fit lid).
However, you can tighten that lid pretty much any time after a week. That's just to get the cabbage to the state where it starts to break down and becomes less chewy.
You'll also find that if your cabbage is packed pretty close to the rim, the gas created during the first week will push out a goodly amount of liquid, so it's also a good idea to put a very full jar into a bowl while it's going through this phase. It's all good as that pushing against the lid helps ensure an oxygen-free environment in the jar. But as long as all the cabbage is under the brine, you're good.
After this you can put it in the fridge. The fridge will slow down the fermentation process but not stop it, so after a week you can taste it. If you like the tang at this point, go head and eat some and take advantage of the various bacterium produced at this particular stage.
If you prefer a sharper-tasting sauerkraut, you may want to put it in the fridge at one week to slow down the next two stages of fermentation. If you like it mellower, let it go 4-6 weeks on the counter. Just make sure the cabbage is below the brine and let it go 4-6 weeks to complete a full bacterial cycle.
Personally, I let it sit on the counter for a month or so while I use up the jar that's in the fridge. As the fridge jar empties, I'll start up a new cabbage and move the one that's been fermenting into the fridge.
How The Fermentation Works
There are already microbes on the cabbage. When we add salt to shredded cabbage, the salt draws out sugar onto the leaves, which eases and accelerates fermentation from those microbes. Keeping the cabbage in the brine inhibits bacteria that we don't want and nurtures the bacteria we do want, which are Leuconostoc and Lactobacillus.
Fermentation happens in three stages. Note the temperatures for optimal growth:
- Leuconostoc mesenteroides start to grow and thrive between 1-3 days at 65-72° F.
- Lactobacillus plantarum and Lactobacillus cucumeris start to thrive at 10-30 days at 72° F – 90° F.
- Lactobacillus brevis (the real sexy one of the gut bacteria) starts to thrive in less than a week at 72° F – 90° F.
Give It a Month
Give yourself a month of adding your own sauerkraut to your meals once or twice a day and see how much more zen and sparky you feel and how much better your training goes.
- Clarke, S. F. et al. Exercise and associated dietary extremes impact on gut microbial diversity. Gut doi:10.1136/gutjnl-2013-306541
- Levkovich T1, Poutahidis T, Smillie C, Varian BJ, Ibrahim YM, Lakritz JR, Alm EJ, Erdman SE. Probiotic bacteria induce a 'glow of health'. PLoS One. 2013;8(1):e53867. doi: 10.1371/journal.pone.0053867. Epub 2013 Jan 16.
- Vethachai Plengvidhya, Fredrick Breidt, Jr., Zhongjing Lu, and Henry P. Fleming. DNA Fingerprinting of Lactic Acid Bacteria in Sauerkraut Fermentations. Appl Environ Microbiol. 2007 December; 73(23).
- Marja Tolonen , Marianne Taipale , Britta Viander , Juha-Matti Pihlava , Hannu Korhonen , and Eeva-Liisa RyhŠnen. Plant-Derived Biomolecules in Fermented Cabbage. MTT Agrifood Research Finland, Food Research, FIN-31600 Jokioinen, Finland J. Agric. Food Chem., 2002, 50 (23), pp 6798–6803.
- Adv Nutr. 2016 Jan 15;7(1):90-101. doi: 10.3945/an.115.010587. Print 2016 Jan.
- Can We Prevent Obesity-Related Metabolic Diseases by Dietary Modulation of the Gut Microbiota? Brahe LK1, Astrup A2, Larsen LH2.
- Curr Opin Gastroenterol. 2016 Mar;32(2):96-102. doi: 10.1097/MOG.0000000000000244. A gut (microbiome) feeling about the brain.
- Sherwin E1, Rea K, Dinan TG, Cryan JF.