Mention the word “detox” to an audience of registered dietitians, and there will be as many different reactions as there are online search results for a “detox diet.” In the context of nutrition and health, the term detoxification is steeped in conflicting information and opposing views.
Detoxification is the biochemical process that transforms non-water-soluble toxins and metabolites into water-soluble compounds that can be excreted in urine, sweat, bile or stool. Because these processes rely on specific nutrients such as flavonoids, minerals, certain amino acids and B-vitamins, there are therapeutic detoxification protocols to support the organ systems through which the body detoxifies.
On the other hand, popular culture teems with detox diet books, fasts, cleanses and products — many fueled by quasi-science and inflated claims of purging the body of toxins without qualifying “toxin” or the mechanisms at play. As a result, much of the medical community eschews the term “detoxification,” dismissing the entire idea as a baseless fad that’s ineffective at best, potentially harmful at worst.
But there is a community of RDs — largely but not exclusively in integrative nutrition — who support reclaiming this word and if not applying nutritional detoxification strategies to promote health and healing, at least clarifying for patients and practitioners what a detoxification diet might look like from a science-based perspective.
Skepticism of dietary detoxification protocols may lie, in part, in the vernacular. In some cases, it is a clash of figurative language vs. literal meaning. Words such as “purify” or “clean” — used to illustrate a point, much in the way that “heavy” and “light” describe the fat and calorie content of foods as opposed to actual weight — are rejected by some practitioners because they are nonclinical words. Lesser-known phrases such as “toxic load” or “body burden” (which refer to the level of internal and external toxin accumulation in the body) are used by other clinicians and researchers. While this supports the argument for standardized language, in the interest of clarity, this article will identify key phrases or concepts that may vary within the nutrition community.
Biochemically, detoxification occurs through two main enzymatic processes. Phase I detoxification, sometimes called “functionalization” or “activation,” is when oxidation, reduction and hydrolysis reactions turn a fat-soluble toxin into an unstable intermediate molecule, resulting in a free radical (a.k.a. “intermediary metabolite”). Phase II detoxification then converts the intermediate molecule into a more stable, water-soluble one through conversion or “conjugation” reactions. The water-soluble molecule can be excreted through urine, bile and feces.
If the body’s Phase II enzymes can’t keep up with Phase I, the result is too many circulating free radicals. If Phase I mechanisms are not functioning efficiently or can’t keep up with the influx of toxins, then those toxins are not neutralized and continue to circulate or become deposited in bone and soft tissue.
The Nutrition Prescription
A general detoxification diet is based on whole foods and includes fruits and vegetables (preferably organic*) and adequate fiber and water. Some foods and nutrients have been found to be particularly effective in “up-regulating,” or revving up, the body’s detoxification pathways:
- Fruits and vegetables: A diet high in fruit and vegetables contributes a wide range of phytochemicals, many of which promote detoxification enzymes.
- Cruciferous vegetables: Compounds in crucifers such as cabbage, broccoli, collards, kale and Brussels sprouts promote enzymes that regulate detoxification in the liver.
- Turmeric: Curcumin in turmeric has been shown to have anti-inflammatory properties and function as an antioxidant in animal studies.
- Green tea: Known for its antioxidant activity, it has been suggested that green tea’s bioactive components are polyphenols — especially catechins such as epigallocatechin gallate, or EGCG.
- Water: The importance of adequate hydration for detoxification cannot be underestimated. Water facilitates urinary excretion and bowel motility, supports the lymphatic system and replenishes fluids lost through sweat.
- Fibrous foods: Soluble and insoluble fiber, as found in flax seeds, beans, oats and brown rice, can bind to toxins and bile and carry them out of the body through the stool. It can also minimize contact with harmful compounds, such as acrylamides from charred meat, by regulating transit time.
- Probiotics: Beneficial bacteria from probiotic supplements or fermented foods such as yogurt and lacto-fermented vegetables protect the intestines and may inhibit the growth of pathogenic bacteria, which produce ammonia and other toxic metabolites.
- Eggs, garlic and onion: Sulfur supports the body’s production of glutathione, an antioxidant sometimes called “the master detoxifier” because it is a critical nutrient co-factor in Phase I and II detoxification.
Many science-based practitioners are reluctant to consider detoxification a legitimate component of natural health and healing based on the perception that recommendations are, across the board, unscientific. It is true that some popular detox diet and product claims are based on preliminary if not questionable studies, but it’s important to not let healthy skepticism become personal bias as research continues to explore the intricacies of detoxification pathways, nutrigenomics, generational effects of toxic exposure and their effects on human health.
After all, detoxification is not the first diet and health concept to be exploited or oversimplified, nor is it likely to be the last — reinforcing the importance for food and nutrition experts to help consumers separate fact from fiction.