Phase I is the first line of defense against toxins in the liver. Phase I reactions occur primarily by cytochrome P450 enzymes, which help transform fat-soluble toxins into less harmful chemicals that can be metabolized by the phase II enzymes. This process produces free radicals, which are quenched by antioxidants (like vitamins C and E). However, if antioxidants can’t meet the demands of excessive toxin exposure, too many free radicals can actually cause damage to the cells in the liver. The danger is if these reactive intermediates build up because they are too numerous to be metabolized by the phase II pathways. Phase II detoxification makes these intermediate metabolites water-soluble via a process called conjugation. This process involves specific pathways that conjugate (attach) molecules to toxins so they can be excreted by the body. There are six major pathways: Finally, phase III detoxification transports the transformed, conjugated toxins into bile or urine for excretion by the intestines, kidneys, and skin. As a whole, a well-functioning digestive system—including the liver, gallbladder, and gut—is hugely important to healthy detoxification. But you can’t optimize detox on fruits and vegetables alone. Many cleansing diets (like juice fasts) are deficient in protein, which inhibits the body’s ability to get rid of toxins via phase II conjugation. Amino acids4, the building blocks of protein, are essential to the six pathways of phase II detoxification mentioned above. You can’t effectively conjugate toxins without amino acids that bind the transformed toxins in the liver so they can be carried out of the body. And if phase II conjugation is impaired, imbalanced detoxification allows phase I free radicals to build up and cause damage. To put it more simply: Protein helps drag toxins out of the body, and without it these toxins build up. All proteins are essential for detoxification, particularly those that contain high amounts of the essential amino acid called methionine. Methionine is an important part of the process called methylation, which was mentioned above. And methylation helps our body to make that critical compound called glutathione. Methionine is most abundant in beef, Brazil nuts, brown rice, chicken, chickpeas, lentils, turkey, pinto beans, sesame seeds, and soy. So don’t demonize soy quite yet. While it is true that overly processed, genetically modified soy is an issue, soy contains compounds that are important for detoxification3. This includes methionine, as well as isoflavones, which influence phase I and phase II liver detoxification and healthy estrogen metabolism. It’s also worth mentioning whey protein. While I’m not a fan of dairy and don’t use whey protein myself, there’s good evidence that high-quality whey protein is one of the best food sources of glutathione. However, this comes with a lot of caveats, and the majority of whey protein you’ll find in stores is not suitable. Whey protein should be biologically active, non-denatured, cold-processed, and derived from organic, grass-fed, and hormone-free raw milk (and only used by people who tolerate dairy well). Omnivores can rely on a variety of high-quality, organic, lean animal protein like pastured eggs, chicken, grass-fed beef, buffalo, and lamb. People who eat fish should choose wild-caught, low-mercury fish like anchovies, clams, flounder, mackerel, oysters, salmon, sardines, scallops, sole, and trout. Most vegetarians can safely rely on organic, non-GMO miso, natto, tofu, and tempeh. High-quality, pure hemp or pea protein powders are also an option. Remember, our body’s ability to detoxify is a complex process that requires a lot of energy from nutrient-dense foods—including organic whole fruits, vegetables, and high-quality protein. Be sure that your body is getting the nutritional support it needs to facilitate the pathways involved in processing and removing toxins. Ideally, this includes some protein at each meal for ongoing support of liver detox. In the end, long-standing, improved elimination and detoxification can help improve fatigue, sleep, cognitive function, mood, and weight loss, to name a few. But just how much protein should you be eating in a day? We got to the bottom of things.