From Chapter 10: Prebiotic Foods And The Phase Two Diet
Polyphenols are a class of antioxidants that are proven to improve the diversity of the microbiome and feed several keystone bacteria. They generally achieve this without creating a lot of gas or bloating, and therefore are usually tolerated by even the most sensitive patients. People living with SIBO or who have intolerance to high-fiber foods are usually able to tolerate foods that contain polyphenols.
So, we begin our discussion about what foods to start adding to the diet with the polyphenol-rich prebiotic foods. If you have found that your diet has become overly restrictive and you don’t know where to start in terms of expanding your diet and reintroducing foods, this is a good place to begin.
Polyphenols from berries have been linked to systemic improvements in blood pressure, cardiovascular status, cancer risk, memory, attention, and other cognitive functions – but they require processing by our gut bacteria into smaller molecules that we can absorb in order to reap these benefits. The old saying, “you are what you eat,” can be expanded: you are what you eat, digest, and absorb (as long as you have the right gut bacteria).
Polyphenols are also relatively heat stable and although there is some amount of loss from heating, it is minimal and most of the prebiotic effects are preserved. Therefore, it is completely fine to use cooked versions of the following foods if necessary. After the descriptions of the foods are some tables that detail their actual polyphenol content.
Clove powder: Clove is actually the richest food source of polyphenols in existence. Add a quarter teaspoon to a smoothie or other beverage, or to any meat or vegetable dish that you are cooking.
Berries: All berries are excellent sources of polyphenols, including blueberry, blackberry, cranberry, strawberry, and elderberry.
Other fruits: This includes cherry, plum, red or black grapes, and red apples (the skin contains the polyphenols). Nuts and seeds. Especially good sources include ground flaxseed, chestnuts, hazelnut, pecan, and black sesame seed.
Vegetables: More intensely colored vegetables such as black or purple carrot, red loose-leaf lettuce, purple cauliflower, red cabbage, and purple potatoes are good sources. Other good
sources are spinach, broccoli, onion, and orange carrot.
Tea: Green or black tea are great sources of polyphenols, antioxidants and other phytochemicals. Green tea is especially beneficial because of its positive impact on the oral and gut microbiota, as we discussed in Chapter 4 and further in the previous chapter. EGCG is one of the most abundant polyphenols in green tea, and regulates inflammation. As I mentioned in the previous chapter, adding a quarter teaspoon of matcha powder, which is very high in EGCG and other polyphenols, to your daily cup of green tea is a great way to boost your polyphenol intake.
Cacao powder: Studies show that cacao powder has unique prebiotic antioxidants called flavanols that increase levels of Lactobacillus and bifidobacterium and decrease levels of potentially pathogenic bacteria such as clostridia; they also reduce inflammation as measured by serum C-reactive protein, and have the metabolic benefit of reducing triglycerides. Cacao also contains magnesium and zinc and is a rich source of polyphenols, which are beneficial for cardiovascular health too. Dark chocolate is an option here since it is made from cacao powder. Aim for a minimum of 70 percent (ideally > 85 percent) cocoa. As I mentioned in Chapter 2, cacao today can contain high levels of lead and cadmium. To find brands that have been independently tested to be low in toxins, visit http://doctorakil.com/toxic-chocolate/