Harley Pasternak is a celebrity trainer and nutrition expert who has worked with stars from Halle Berry and Lady Gaga to Robert Pattinson and Robert Downey Jr. He’s also a New York Times best-selling author, with titles including The Body Reset Diet and The 5-Factor Diet. His new book 5 Pounds is out now.
Ten thousand years ago, long before the words artificial and preservative were joined at the hip, our Neolithic forebears discovered that fermented foods could be stored, which helped ward off starvations whenever pickings were slim. Today, few of us are in survival mode, but the added virtues of tastiness and nutritional value have kept this ancient preservation technique alive.
Virtually every culture has made fermented foods integral to its cuisine.
Japanese and Chinese cooking relies on fermented soy products such as miso (fermented soy beans), soy sauce, and tempeh. Germans love their sauerkraut; Russians, their borscht. Koreans serve kimchi, spicy pickled vegetables, at almost every meal. Fermented milk turns up as Icelandic skyr and Greek yogurt.
Fermented — specifically, lactic-acid fermented — foods are experiencing a resurgence of interest today, both for their complex flavors and their health benefits. These foods are probiotic, meaning they contain beneficial bacteria. Activated bacteria, fungi, and yeast microbes feed on starches and sugars, converting them to lactic acid, which creates new compounds in the form of enzymes. Because both the enzymes and microbes are alive, pasteurization or temperatures much over 100° will kill them, a factor to keep in mind both when selecting products and when preparing meals that use fermented foods.
Bring on the Good Bacteria
Fermentation doesn’t just enhance the flavor of food; it also improves digestion. With ongoing study of the human Microbiome, we now have a better understanding of its beneficial effects on the gut. Fermented foods play an important role in keeping our gut bacteria healthy, promoting the growth of more good guys and crowding out the bad guys. Eating such foods regularly should ensure a healthy colon, along with the rest of your digestive tract. Fermented foods are great multitaskers. By introducing healthful bacteria, they perform at least five important functions:
1. Make food more digestible. Beneficial bacteria help predigest foods, such as seeds and beans, that can be difficult for your body to do on its own. They do so by more efficiently breaking proteins into individual amino acids, carbohydrates into individual sugar molecule, and fats into individual fatty acids. These smaller compounds can then be more easily absorbed as nutrients and energy.
2. Boost regularity. Fermented foods assist the body in producing a neurotransmitter called acetylcholine, which is responsible for transmittingnerve impulses, including messages to the bowel, helping reduce the likelihood of constipation.
3. Add valuable nutrients. Not only are vitamins, minerals, and other micronutrients more bioavailable, but fermented foods also provide beneficial enzymes.
4. Balance stomach acid. Although many people are focused on heartburn and acid reflux, too little stomach acid (hydrochloric acid) can be as problematic as too much, particularly production declines with age. On the other hand, if the level of hydrochloric acid is too high, fermented foods help protect the lining of the GI tract from the damage known as leaky gut.
5. Moderate blood sugar. By breaking down sugars and other carbohydrates into smaller components, fermented food slows the entry of glucose into the bloodstream, reducing the burden on the pancreas to constantly deliver insulin.
Four Healing Foods
If you’re ready to try some lactic-acid fermented foods, here are four of my favorites. Some are readily available in most well-stocked supermarkets. Depending upon where you live, you may need to order others, such as miso, online. And one is best purchased as a real old-fashioned bakery or farmer’s market.
1. Kefir. I’ve lauded the virtues of Greek yogurt and Icelandic skyr in other blogs. This fermented beverage known as kefir is a close relative with some significant differences, including its consistency. Yogurt also generally contains only transient bacteria: they do their job and depart via your GI tract. Kefir, on the other hand, usually contains more and a greater variety of good bacteria that are capable of actually colonizing the GI tract. In addition to a variety of bacteria species, kefir also boasts beneficial yeasts that banish destructive yeasts living in your gut, so you are better able to resist pathogens such as E. coli.
Look for: Kefir needn’t be a dairy product. In addition to kefir made from cow, goat or sheep milk, you can also find coconut, rice or soy kefir. Purchase plain, unflavored, unsweetened products, as many varieties are loaded with sugar. You can add fruit or other flavorings to make a kefir smoothie.
2. Miso paste. This bean paste — it also sometimes contains rice or barley — is fermented with salt and a fungus called Aspergillus oryzae, which has strong probiotic properties. In addition to traditional soybeans, miso is also made with chickpeas (garbanzos) and other legumes. You have probably had traditional miso soup in Japanese or Chinese restaurants, but nothing could be easier than making your own variations. Stir a spoonful of miso into any hot (but not boiling) vegetable-based soup to make it infinitely more interesting. Whisk miso with olive oil and a little rice vinegar for a flavorful salad dressing or omit the vinegar to give a boost to grains or cooked vegetables. It also makes a great marinade for grilled or baked fish or chicken.
Look for: Miso comes in shades of red, white, yellow, and brown. Aged miso is saltier and more assertive than “younger” versions. White miso is generally the sweetest, and may be a good place to start exploring this ancient convenience food. Select an organic product to avoid monosodium glutamate (MSG) or GMO beans.
3. Sourdough bread. If you’re going to make bread, sourdough is the way to go. Instead of using commercial yeast as a rising agent, sourdough employs a starter, called a “mother.” This living, fermented mash full of Lactobacillimay initially require some store-bought yeast, but from then on, it reproduces its own. The probiotic bacteria break down more of the gluten, making it more easily digested than other bread, but this also means a longer preparation time, which is assembly line bakeries offer it. Most bread has a high glycemic index, but sourdough does not raise blood sugar levels precipitously. It is questionable whether the live bacteria can survive the baking process, but advocates claim that they have used their own sourdough bread to make new starter! Nonetheless, sourdough bread does offer more vitamins and minerals than most commercial alternatives.
Look for: Recipes for starter and bread abound on line, but if you can’t make your own, avoid the so-called sourdough bread found in most supermarket bakeries or packaged products. Both are typically made with conventional yeast and perhaps other rising agents. Your best bet is an artisan baker or vendor who sells at farm markets. Look for a whole grain loaf, and ask the source of the sourdough and a list of ingredients. The bread should contain just flour, water, salt, “wild yeast,” and perhaps some sprouted grains.
4. Sauerkraut. If you associate this tart cabbage slaw only with hot dogs and Reuben sandwiches, think again. Real lactic-acid fermented sauerkraut, as opposed to the vinegar-soaked version that comes in cans, is another probiotic powerhouse. According to a Finnish study, sauerkraut’s known anti-carcinogenic properties are magnified by the fermentation process, thanks to the production of isothiocyanates that stop the growth of cancer cells. Sauerkraut is a great staple to have in the kitchen when you need to toss together a meal ASAP. Simply slice and sauté some turkey sausages or leftover meat or poultry, add some kraut and perhaps an apple to cut the tartness, simmer for a few minutes and you’ll soon have a nutritious meal on the table. Serve over brown rice or whole grain noodles if you wish. Drained kraut added to unsweetened pancake batter makes a great savory dish. Serve the pancakes with a splash of soy sauce, another fermented food.
Look for: There are numerous and varied recipes for making sauerkraut online, but if you prefer to purchase it your best bets are Whole Foods or local natural foods stores. Look for brands such as Hawthorn Valley, Hampton’s Brine, or Tropical Traditions, all of which can also be ordered directly.
I hope I’ve teased your taste buds with these new-again ancient foods. I know your gut “bugs” will thank you for incorporating some or all of them into your diet.