It may be hard to believe that by taking a probiotic like kefir, you can alter the composition of your gut bacteria in a way that positively affects your mood and brain function, while also resolving your irritable bowel syndrome (IBS). But a massive wave of research into the brain-gut axis has shown exactly that.
Kefir—a fermented product similar to liquid yogurt—has been around for millennia, but today it's poised to become a major player in a new frontier in neuroscience because of its actions as a 'psychobiotic.' This is a new term for a combination of live organisms that, when ingested in adequate amounts, produce mental health benefits.
While it's been known for over a century that bacteria can have positive effects on our physical health, it's only in the last 10-15 years that studies have shown there's a connection between the gut, the bacteria in the gut and the brain.
In mice, enhanced immune function, better reactions to stress, and even learning and memory advantages have been attributed to adding the right strain of bacteria to the gut.1
"Those studies give us confidence that gut bacteria are playing a causal role in very important biological processes, which we can then hope to exploit with psychobiotics," says Philip Burnet, an associate professor of psychiatry at the University of Oxford.
Psychobiotics have been largely studied in groups of IBS patients where positive results were seen on their IBS and their depression/anxiety.2
But you don't need to be clinically depressed to benefit from psychobiotics.
The latest research shows that anyone suffering from chronic stress, low mood or anxiety-like symptoms can benefit from them as well.3
How do psychobiotics work?
Psychobiotics work on the brain in three different ways:
1) By producing active compounds like serotonin that work on the gut-brain axis. When our gut secretes serotonin, this triggers cells within the gut lining to release molecules that signal brain function and affect behavior.4
2) By working on the body's stress response system, which involves the brain and the adrenal glands (at least in animal studies).5 This system, also known as the hypothalamic-pituitary-adrenal (HPA) axis, is damaged by chronic stress or illness. When your HPA axis is out of whack, the production of cortisol and other stress-related hormones goes wrong as well.6
This plays a big part in causing mood disorders and cognitive problems.
3) By affecting the brain through their anti-inflammatory actions. Chronically elevated levels of inflammation throughout the body and brain are now known to be one of the major underlying causes of IBS, depression and anxiety. This inflammation can stem from the gut, and psychobiotics affect the brain by lowering inflammation.7
Psychobiotics can also help boost mood and ease anxiety in people suffering from various chronic diseases. Beneficial bacteria were used in a double-blind, placebo-controlled trial in patients with chronic fatigue syndrome, and the participants taking the probiotic had a significant decrease in anxiety symptoms compared to the control group.8
In another trial, psychobiotics were shown to help people during times of stress by preventing stress-related cortisol increases while raising serotonin levels.9
For those with IBS, research has found that daily treatment with a psychobiotic for four weeks led to improved mood, reduced anxiety scores and significantly improved quality of life in IBS sufferers.10
Recent science has also shown that psychobiotics may relieve symptoms of depression. In a 2017 study, researchers from McMaster University in Canada found that twice as many adults with IBS reported improvement in coexisting depression when they took a psychobiotic compared to those who took a placebo.
The study provides further evidence that the microbiota environment in the intestines is in direct communication with the brain.11
In fact, one study comparing psychobiotic bacteria to the SSRI citalopram showed that the bacteria actually worked better than the medication in dealing with depression, anxiety and cognitive dysfunction due to chronic stress. It lowered cortisol and restored levels of serotonin and other brain chemicals to normal.12
Guidelines for making your own kefir
Working with live cultures can be a wonderful boon to health. It's easy to make your own kefir at home: kefir grains can be ordered online.
Like anything, however, homemade kefir has both benefits and potential risks—and often the risks are not described in the instructions that accompany the grains.
So, in order to ensure that your homemade kefir is safe for consumption, please observe the following food safety guidelines.
1) Ferment your kefir until the pH is below 4.5. This is the level at which most bacterial pathogens are unable to survive. pH meters are widely available for this purpose.
2) Drop the pH of your kefir down to 4.5 or below as rapidly as possible. Although it's fine for the entire fermentation process to take up to 48 hours, this initial drop in pH needs to happen quite quickly—ideally within the first 16 hours of fermenting. Otherwise you run the risk of spoilage bacteria entering your kefir.
3) The ideal ratio of grains to milk is about 1:7. Fermentation rates vary, depending on heat and activity (both of which increase fermentation rates), so keeping your kefir warm and shaking it from time to time will speed up the fermentation process.
4) Test your finished kefir once a month at a public health laboratory, to ensure your grains have not become contaminated. Whenever you reuse a live culture (such as kefir grains), you run the risk of bacteriophage contamination.
Bacteriophages, or 'phages,' are viruses that infect bacteria, and they can turn harmless bacteria into agents of disease by altering their genetic code to produce toxic substances. These bacteria are then able to infect humans and cause food poisoning and other potentially deadly diseases.
If you contact the public health laboratory near you, they can explain how you can bring in your kefir for testing. Ask for a standard microbiological food safety screen for a live culture product.
How to take your kefir
Kefir is strong stuff, so I recommend you start slowly. Take 1 Tbsp of kefir per day, and as your system adjusts, work your way gradually up to a daily dose of up to 6 fl oz.
Choose pure goat's milk kefir that's been made with real kefir grains, with no added sugar, sweeteners or flavorings. Drink it first thing in the morning on an empty stomach.
Why on an empty stomach? Because tryptophan, the precursor to serotonin that kefir is packed with, only works on the brain when consumed on an empty stomach.
Why first thing in the morning? Because the lactate in kefir (not lactose: kefir is 100 percent lactose free) will give you an energy boost, and you don't want that last thing at night or you'll have trouble getting to sleep.
Make sure to give other liquids 15 minutes or so to clear your system before you take your kefir. The idea here is to give the live bacteria in the kefir a nice clear run at the wall of the gut, to which they'll adhere and begin fighting for space with the bad bugs that are parked there, and start pushing them out.
You can sweeten your kefir by adding 100 percent stevia or blend it up with fruit, but if you do the latter, be sure to consume it immediately. Don't let it sit overnight, as the fructose (fruit sugar) will degrade the power of the probiotics.
Regular bread containing gluten is not recommended while trying to heal a gut-based condition, but here are two gluten-free options that you can have instead.
Pancakes are considered a staple food by many families, but they are typically considered off-limits outside of breakfast, and when they are served, they're smothered in high-GI maple syrup. And in many European countries, if they're eaten at all, they're doused in powdered sugar.
So, I officially encourage you to reboot your ideas about pancakes. A pancake is just a simple flat bread cooked on a griddle or in a frying pan and nothing could be faster, easier or more tempting.
We fry up a stack of the following 'save-my-snacktime' pancakes every three days or so, wrap them up and store them in the fridge (where they'll keep for up to four days).
For a snack, or lunch, you can then pop them in the toaster to make them warm and crispy. They can be sweet or savory—serve them with the topping of your choice from the suggestions below.
Makes 8 pancakes
17 fl oz kefir
7 fl oz goat's milk
1 free-range egg
8 oz gram flour
7 oz other gluten-free flour—choose from buckwheat, quinoa, sorghum, millet flakes or coconut flour
1 Tbsp potato starch (not potato flour)
1 tsp baking soda
½ tsp sea salt
Goat's butter or coconut oil
1) Combine the kefir, egg and goat's milk.
2) In a medium bowl, mix the flour, baking soda and salt.
3) Melt 1 Tbsp of the goat's butter and pour onto the dry ingredients.
4) Incorporate the flour slowly into the kefir mixture to produce the batter. (Make sure the batter is not thin and soupy, otherwise you'll get crepes. It should be a nice firm batter that is pourable. If the batter is too thin, add more flour.)
5) Heat a griddle or frying pan to medium heat and add about 1 Tbsp of goat's butter/coconut oil. Scoop the pancake batter with
a ladle and pour into
6) Cook each pancake for a few minutes on each side. Flip them over when you see bubbles appear on the surface.
If you like a sweet pancake, add 100 percent pure stevia to taste, or top it with fruit, such as blueberries or strawberries. If you prefer yours savory, add butter, soft goat's cheese, hummus, guacamole, peanut butter or almond butter.
Kefir soda bread
This bread is hearty and crumbly. It's a bit challenging to make sandwiches with it, but it's a great complement to soups, stews and slow-cooked meals.
8 fl oz kefir (milk or water kefir)
4 oz organic buckwheat flour
2 oz organic quinoa flour or oat flour (if tolerated)
2 oz organic almond flour/meal
1 oz soaked oat groats (optional)
Pinch sea salt
1 tsp baking soda
1) Put the buckwheat flour and the kefir in a glass bowl. Soak overnight, or for at least 12 hours.
2) Preheat the oven to 400°F.
3) Sieve the remaining dry ingredients into a glass bowl, then add the wet ingredients. Try to mix them as little as possible. Leave the dough in the bowl for 10 minutes.
4) Add a little flour to your hands. Put the dough (leave it in the shape it took while in the bowl) on a baking tray lined with a greased sheet of parchment paper. Dust the dough lightly with a bit of gluten-free flour and cut a deep cross in the top.
5) Bake for 30 minutes until brown on the outside. Enjoy warm, dripping with goat's butter!
1 Trends Neurosci, 2016; 39: 763-81
2 Biol Psychiatry, 2013; 74: 720-6
3 Gastroenterology, 2013; 144: 1394-401
4 Adv Exp Med Biol, 2014; 817: 221-39
5 Neurogastroenterol Motil, 2014; 26: 510-20
6 Psychiatry, 2006; 5: 166-70
7 Clin Ther, 2015; 37: 984-95
8 Gut Pathogens, 2009; 1: 6
9 Benef Microbes, 2016; 7: 153-6
10 Aliment Pharmacol Ther, 2009; 29: 508-18
11 Gastroenterology, 2017; 153: 448-59.e8
12 Neuroscience, 2015; 310: 561-77