Yogurt, Kefir, And Fermented Foods
We love fermented foods for ourselves and the pups, here's why
Hi guys! This week we visited the Oregon Humane Society in Portland and brought a special meal for Hot Pocket, a pup that’s been there a while. He is looking for a loving home with someone that is active and will embrace the challenge of exercising and training him daily. He’s been returned twice for being very high energy. Let’s hope that third time is the charm. If you or someone you know may be the right fit, check out his profile here: Adopt Hot Pocket!
Onto today’s topic:
We are huge fans of yogurt, kefir, aged cheeses and other fermented foods for the pups and ourselves. Most people know that yogurt and fermented foods can be good for us, but there is actually a lot of differences between types of fermented foods. Some can even be bad for us. Today we do a deep dive into the literature, share what we feed the pups, and also share some details about our own diets. Before that here is a new recipe that uses yogurt, and an old recipe that we refreshed for Hot Pocket:
Partially rotted food is good for you?
Fermentation is older than written human history. There is archeological evidence of fermented beverages going back nearly 10,000 years in China where ancient vats were discovered to contain residue of fermented rice, honey and fruit alcohol. Wine making in Europe goes back at least 7000 years, while beer and bread making in ancient Egypt dates back 5000 years or more.
Originally, fermentation was about survival, not health. Due to the lack of refrigeration, food preservation was essential to prolong the shelf life of perishable foods. Summer and fall harvests were stretched into winter and beyond with these methods. When food was scarce, preserved food provided essential sustenance.
Like most things, the discovery of fermented food was likely accidental as early humans had no idea of microbes like bacteria and yeast. Macerated fruit that was left out for long periods developed carbonation, acid and alcohol. Foods that were salted changed flavor and texture, while milk stored in animal stomachs curdled and turned slightly sour. These various methods allowed food to last longer. It was only in modern times that scientists discovered that many of these fermented foods had health benefits...but not all fermented food is created equal.
Not all fermented food is good for you or your dogs
Wines and beers are not only high in ethanol (the compound that gets you drunk and makes you sick), most commercially available beverages contain preservatives and additives. These preservatives and additives are fine for people in small amounts, but about 1% of people may be sensitive. Also, because alcohol is addictive, many people drink excessively and thus consume large amounts of these additives and preservatives.
Cured meats are another type of fermented food not considered to be beneficial for health. They are high is sodium, nitrosamines and preservatives. Sodium is essential in moderate amounts but can raise blood pressure in sensitive people. Though dogs can tolerate lots of salt, a sudden increase can stress their bodies, especially older or sick dogs. Nitrosamines are linked with cancer, while preservatives can harm beneficial bacteria in the microbiome. Bacon, sausage and salami and other high fat cuts are also high in saturated fats which is linked with higher cholesterol in people.
Some pickled foods are made to mimic the taste of fermented foods, but have none of the probiotic effects. Other fermented foods are pasteurized to destroy the bacteria before packaging to ensure consistency. Though these pasteurized foods my contain prebiotics (food for beneficial bacteria) and fiber, they lack the actual microorganisms that increase microbiome diversity.
Why do we want microbes in our foods?
There are likely more microorganism cells that live in your body than the total number of human cells. The same is true for your dog. These critters are called the microbiome and they live symbiotically with their hosts. Fermented foods help support this microbiome.
The microbiome is so important that diversity of species is positively associated with good health outcomes. This just means that the more different kinds of critters that live in an animal’s guts, the healthier they tend to be. People think of bacteria as bad, but in our guts the opposite is true. The microbiome has a lot of functions and the more species there are, the higher the likelihood of having a lot of different abilities in the microbiome. Here’s a short list of the things that the microbiome does. See this research review for more details:
Digestion: gut flora excrete short-chain fatty acids (SCFAs) that are linked with lower inflammation, improved immune function and metabolic health.
Vitamin production: Many essential vitamins are made by the microbiome including, B12, K2, biotin and folate.
Pathogen defense: Good bacteria outcompete pathogens like E.coli and Salmonella, reducing the likelihood of illness when they are ingested.
Brain function: The gut is directly connected to the brain through something called the gut-brain axis. The microbiome affects mood, hormones and stress response.
Metabolic signaling: Though research is still emerging, there is evidence that the microbiome affects fat storage, hunger hormones and blood sugar response. Poor microbiomes are associated with obesity and diabetes.
In a rigorous study conducted at Stanford one group of people ate a high fiber diet without fermented foods while another group ate a high fiber diet with fermented foods. Researchers concluded that fiber alone was not enough to impact the diversity of the microbiome. Not only did the fermented food group have increased microbiome diversity they also had lower inflammation markers.
What kind of fermented foods we feed and eat
The simplest way to make yogurt is to include just two strands of bacteria. Lactobacillus bulgaricus and Streptococcus thermophilus strains consume sugars (like lactose) and excrete a number of compounds like lactic acid and exopolysaccharides. The lactic acid helps to break down the proteins making them easier to digest. Exopolysaccharides feed other beneficial strains of bacteria, and is thus a helpful prebiotic.
Yogurt is great for people and pups because of the easily digestible proteins and prebiotics. But most yogurt doesn’t have enough variety of species to be a great probiotic. We prefer kefir and premium yogurt over the cheap stuff because of the diversity of microbes. As the proteins are more easily digestible and the lactose is mostly converted into other metabolites, yogurt and kefir made from cows milk doesn’t irritate dogs’ stomachs (like regular milk can).
In addition to yogurt and kefir, we eat lots of fermented foods from kimchi, miso and sauerkraut to fermented beverages like kombucha. Though we wouldn’t give kimchi and miso to the dogs (spicy, salty, etc) they can have a bite of sauerkraut if it’s made with just cabbage and salt.
What about probiotics?
Probiotics are bacteria that are selected by manufacturers for specific health benefits. Then they are cultivated, harvested, and processed into a shelf stable form. Finally, specific formulations are blended, encapsulated, and bottled. Taking probiotics is super convenient for those who don’t mind pills. However, they can be very expensive, and the evidence suggests that fermented foods are at least as good as commercially available probiotics to improve microbiome diversity. Many experts believe that fermented food is superior for general gut health because of the other metabolites and prebiotics as discussed above.
Although most of our probiotics come from fermented food, we find some probiotic supplements to be beneficial in addition to fermented food. S. boulardii (an active ingredient in Pupto Barko) has shown to relieve chronic gastric disorders in dogs better than standard treatment alone. Because S. boulardii is a yeast rather than a bacterium, it is tolerant of antibiotics. There are others strains which have been shown to be effective for things like managing eczema in children or improving immune function. Ultimately, for general gut health, fermented food is both economical and effective.
Conclusion
Dogs and humans host a huge number of microorganisms. Adding to the diversity of these microorganisms through fermented foods is a practical way to improve health and digestion. The evidence suggests that the benefits go way beyond just gut health and extend to brain health and hormone balance as well as improving immune function and metabolic health. Though eating a variety of fermented foods is best, simply starting with some yogurt (plain, unsweetened) can be very beneficial.