Feeding Metabolic Detox

More commonly known as metabolic detoxification, biotransformation is the normal physiologic process of converting toxicants from the environment and from the body itself into compounds that can be safely mobilized and excreted from the body.

Biotransformation is accomplished through myriad metabolic detoxification pathways that take place in every tissue and organ, even the lungs and brain.

A properly functioning detoxification system maintains a proper balance of hormones, metabolizes pharmaceuticals, and processes harmful substances from the environment to ensure overall health and well-being. An accumulation of toxins is associated with obesity, type 2 diabetes, and cardiovascular disease.

Metabolic detoxification pathways

There are several families of detoxification enzymes, most of which perform these main functions of biotransformation:

Phase I involves the chemical modification of toxins into reactive intermediates, at which stage they actually become more harmful.

Phase II neutralizes these reactive intermediates and makes them water soluble so they may be safely excreted from the body.

Antioxidant support needs to be in place to protect the body from any damage caused by the reactive intermediates produced in phase I.

Nutrients for detoxification

Certain nutrients wield the power to increase the activity of detoxification enzymes and recruit corresponding metabolic detoxification pathways. Since our regular food choices affect the activity of detoxification pathways to assist with toxin biotransformation, they also affect the body’s sensitivity to toxic substances.

New research suggests that diets rich in phytonutrients (nutrients from plant-based foods) may offset toxicity from pollutants and reduce disease risks associated with environmental toxicity. Polyphenols are one type of phytonutrient and are particularly high in berries, cloves, cacao, nuts, and vegetables such as artichokes.

CYP1A detoxification enzymes

Part of the cytochrome P450 family of phase I detoxification enzymes, these enzymes play an important role in metabolizing procarcinogens, pharmaceuticals, and hormones. Lower CYP1A2 enzyme activity has been associated with a higher risk of testicular cancer.

Cruciferous vegetables, including broccoli, cauliflower, and Brussels sprouts, have been shown to increase the activity of CYP1A1 and CYP1A2 enzymes. In doing so, this benefits estrogen metabolism. Resveratrol also enhances the activity of CYP1A1, and can be found in foods such as grapes, peanuts, and soy.

CYP2A detoxification enzymes

This family of enzymes is involved in the metabolism of pharmaceuticals, hormones, environmental toxicants, ketones, and fatty acids. Broccoli and foods rich in the bioflavonoid quercetin (spinach, apples, onions) have been shown to enhance the activity of CYP2A6. Early research suggests that rosemary and garlic may upregulate CYP2B activity.

Glutathione

This is the master antioxidant of the liver, which is involved in both phase I and phase II detoxification pathways. We need to constantly replenish glutathione by sourcing its nutritional precursors from the diet. Vitamin B6, the minerals selenium and magnesium, and the amino acid cysteine are key building blocks for producing glutathione.

For the richest sources of vitamin B6, opt for chickpeas, skipjack tuna, wild salmon, and chicken breast. Pumpkin seeds, almonds, legumes, and leafy greens provide ample magnesium. Cysteine is found in protein-rich animal meats such as pork chops, beef, and chicken breast.

Eating salmon twice per week has been shown to increase glutathione in pregnant women.

Causes of low glutathione

Chronic inflammation has been shown to contribute to oxidative stress and decrease glutathione stores. Those with inflammatory conditions should incorporate more foods rich in glutathione’s nutritional precursors to encourage glutathione production.

Impaired protein digestion and low stomach acid may also interfere with healthy glutathione levels. Seniors and those on medication for acid reflux are at a higher risk of these issues. If this is you, ask your health care practitioner for recommendations on supporting your digestion and absorption.

Depleted glutathione stores may improve through supplementation with curcumin, milk thistle, folic acid, alpha-lipoic acid, and liposomal glutathione.

The genetics of biotransformation

Genetic variations in detoxification enzymes alter one’s sensitivity to toxic substances and the functional capacity of detoxification. Variants in toxicant metabolism have been associated with increased risk of miscarriage, birth defects, Alzheimer’s disease, cancer, and toxicity of both benzene and mercury.

The good news is that once you have done your genetic testing, you can develop an individualized nutrition plan with a health care practitioner to fine-tune your detoxification pathways. In some cases, it might actually be helpful to reduce the activity of detoxification enzymes if your genetics show that it may be overactive and causing harm.

Luckily, there are foods for that, too! Berries can be helpful for reducing overactive CYP1A1, and foods rich in quercetin may reduce excessive CYP1A2.