Coffee, Cruciferous Vegetables, Garlic: The Best Foods for the Phases of Detoxification
You don't need to buy a 49 euro powder to support your liver. Much of what it needs for its work is already in your kitchen. The only question is: which food speaks to which step of the process?
Your liver doesn't need a cleanse to rescue it. It works every day, every hour, without any label. What may do it good is not a miracle product, but a plate that regularly hands it the right tools.
May I ask you an honest question? How often have you stood in front of a shelf of detox teas, green powders and liver capsules and thought: maybe I need this? You feel heavy, a little puffy, somehow not quite clear. And the packaging promises to change exactly that.
I understand that impulse well. You want to do something. You want to give your body something good. That is exactly what this article is about. Only we won't look at the shelf, we'll look in your kitchen. And we'll match each food to the step of the process it can address according to current knowledge.
If you don't know the basics yet, read my article on phase 1 and phase 2 first. Here we build on it and turn it into something you can cook tonight.
What to expect here
- The three steps of detoxification in one picture
- Which food fits which phase
- Cruciferous vegetables: sulforaphane and the Nrf2 switch
- Why raw and cooked make a difference
- Garlic, onion and the sulfur building blocks
- Coffee and the liver: what studies show
- Limits: grapefruit, pregnancy, thyroid
- Three levers for your everyday life
Which foods may support the liver in detoxification?
Imagine your liver as a recycling plant. Deliveries arrive every day: leftovers of hormones, medications, alcohol, substances from the air, breakdown products from your own metabolism. None of it can simply be left lying around. Everything has to be sorted, converted and transported away.
This plant works in three halls. In the first, things are converted. In the second, they are packaged. In the third, they are loaded and shipped out. Each hall needs different tools. And this is exactly where food comes into play.
Phase 1: Converting
Cytochrome P450 enzymes such as CYP1A2, CYP2E1 and CYP3A4 change substances chemically, mostly through oxidation. This can temporarily create more reactive intermediates.
Phase 2: Packaging
Enzymes such as glutathione S-transferases attach the intermediates to glutathione, glucuronic acid, sulfate or glycine. This makes them water-soluble and usually less harmful.
Phase 3: Excreting
Transporters move the packaged substances into bile and urine. They leave the body via the gut, provided digestion works regularly.
The rhythm
What matters is the interplay. If phase 1 runs fast and phase 2 runs slow, intermediates can back up. Food can act at both points.
Most lists on the internet throw everything into one pot: lemon, ginger, turmeric, broccoli, green tea. Sounds healthy, but it doesn't tell you what actually happens. That's why I sort things differently here. Not by superfood shine, but by step of the process.
| Food | Phase | What's behind it |
|---|---|---|
| Broccoli, Brussels sprouts, rocket, cress, cabbage | Phase 1Phase 2 | Glucosinolates are converted into sulforaphane and other isothiocyanates. They can stimulate CYP1A2 and glutathione S-transferases, shown in human dietary studies. |
| Garlic, onion, leek | Phase 1Phase 2 | Sulfur compounds such as diallyl sulfide inhibit CYP2E1 in animal models and can stimulate phase 2 enzymes. They also supply sulfur for conjugation. |
| Coffee | Phase 2Liver protection | Polyphenols such as chlorogenic acid might address Nrf2. In observational studies, coffee is associated with less liver cirrhosis. |
| Legumes, seeds, oats, eggs | Phase 2 | Cysteine, methionine and glycine are building blocks for glutathione and glycine conjugation. |
| Carrot, celery, parsnip, parsley | Phase 1 | In a controlled study, apiaceous vegetables slowed CYP1A2 activity. A counterweight, not a flaw. |
| Fibre, bitter compounds, water | Phase 3 | They keep bile and gut moving, so that what has been packaged can actually be excreted. |
| Grapefruit, pomelo | Phase 1 | Furanocoumarins can inhibit CYP3A4 in the gut. Important above all with medication. |
Detoxification is not an event you trigger with a cleanse. It runs continuously.
So the question is not: how do I detox thoroughly once? The question is: what do I put on the plant's conveyor belt every day?
And now you know why matching foods to phases gives you more than any superfood list.
Cruciferous vegetables: how broccoli may flip the Nrf2 switch
Do you know that slightly sharp, almost mustard-like taste when you bite into raw cress or rocket? That's no coincidence. That's chemistry in real time. In that moment, a precursor turns into a molecule that is among the best studied plant compounds for detoxification in research.
Cruciferous vegetables store so-called glucosinolates. On their own, they are fairly inert. Only when you chew or cut does the glucosinolate meet the enzyme myrosinase, which waits in other cell compartments of the plant. Imagine the two components of a two-part glue. Only when mixed does the active substance form. In broccoli it is called sulforaphane.
In 1992, a team led by Paul Talalay at Johns Hopkins University searched specifically for the compound in broccoli that stimulates protective enzymes. They isolated sulforaphane as a particularly strong inducer of phase 2 enzymes such as quinone reductase and glutathione S-transferases, without also stimulating the receptor-dependent phase 1 enzymes.
What this means for you: broccoli doesn't supply a toxin catcher, but a signal that can ramp up the body's own packaging machinery. The data come from cell cultures and mice.
Zhang Y, Talalay P, Cho CG, Posner GH. Proc Natl Acad Sci U S A. 1992;89(6):2399-2403. DOI: 10.1073/pnas.89.6.2399The mechanism behind it is called Nrf2. This is a transcription factor, a kind of master switch in the cell nucleus. Normally it is held in place and broken down. Sulforaphane can loosen this brake. Nrf2 then moves into the nucleus and switches on a whole group of protective genes. Among them are genes for glutathione production and for phase 2 enzymes.
Seen through the KPNI lens, this is fascinating, because Nrf2 doesn't only concern the liver. This switch sits in many cells, including immune cells and nerve cells. It governs how well a cell can cope with oxidative stress. Detoxification, regulation of inflammation and energy metabolism hang on a shared thread here.
In 2014, Patricia Egner and colleagues from the Johns Hopkins Bloomberg School of Public Health studied people in Qidong, a region in China with high air pollution. For twelve weeks, 291 participants drank either a broccoli sprout beverage or a placebo every day.
In the broccoli group, excretion of the glutathione-bound breakdown products of benzene rose by 61 percent and of acrolein by 23 percent. What this means for you: phase 2 can be measurably influenced in humans by a plant compound. It is important to note that this was a concentrated beverage, not a usual portion of vegetables.
Egner PA, Chen JG, Zarth AT et al. Cancer Prev Res (Phila). 2014;7(8):813-823. DOI: 10.1158/1940-6207.CAPR-14-0103And what about completely normal vegetables? There is a very helpful analysis on that.
In 2020, Shane Eagles and colleagues from the University of Sydney analysed all human dietary studies in which cruciferous vegetables were tested on drug-metabolising enzymes. They found 23 intervention studies with broccoli, Brussels sprouts, cabbage, cauliflower, radish and watercress.
Cruciferous vegetables increased the activity of CYP1A2 by about 20 to 40 percent and of GST-alpha by about 15 to 35 percent. What this means for you: vegetables on your plate can address phase 1 and phase 2 at the same time. And they can change the levels of some medications.
Eagles SK, Gross AS, McLachlan AJ. Clin Pharmacol Ther. 2020;108(2):212-227. DOI: 10.1002/cpt.1811Raw, steamed or boiled?
This is where it gets practical. Myrosinase is heat-sensitive. If you cook broccoli for a long time, the enzyme is lost. Part of the glucosinolate can then still be converted by gut bacteria, but considerably less.
In 2000, a research team at the American Health Foundation in New York compared in twelve men how much isothiocyanate reaches the urine after 200 grams of fresh or steamed broccoli. After fresh broccoli it was on average 32.3 percent of the amount ingested, after steamed 10.2 percent.
Bioavailability from fresh broccoli was therefore about three times higher. What this means for you: briefly cooked or raw is worth it if you want sulforaphane.
Conaway CC, Getahun SM, Liebes LL et al. Nutr Cancer. 2000;38(2):168-178. DOI: 10.1207/S15327914NC382_5A kitchen trick I like to pass on: when you cook broccoli, sprinkle a little raw mustard, rocket or cress over it afterwards. These bring their own active myrosinase. This is mechanistically plausible, though the data on it are still limited.
It is well established that cruciferous vegetables can measurably influence phase 1 and phase 2 enzymes in humans. A 2019 review by Yoko Yagishita, Jed Fahey, Albena Dinkova-Kostova and Thomas Kensler counted more than 3,000 publications and more than 50 clinical trials on sulforaphane.
What remains open, however, is which dose from normal vegetables has which clinical benefit. The authors emphasise that animal doses and human doses are hard to compare and that reliable biomarkers are still lacking.
Broccoli doesn't catch toxins. It reminds your cells to sharpen their own tools.
That is a subtle but important difference. You are not replacing your body's work. You are giving it a nudge.
And now you know why, with cruciferous vegetables, I always ask about preparation and not just quantity.
Garlic, onion and the power of sulfur
Maybe you know this: after a meal with lots of garlic, you can still smell it on your skin the next day. Unpleasant, perhaps. But also a sign that these sulfur compounds really do travel through your metabolism.
Sulfur is a central raw material for phase 2. Glutathione carries it in the form of cysteine. Sulfation needs it as sulfate. Without enough sulfur, the packaging department lacks part of its material. Alliums such as garlic, onion, leek and chives are, alongside cruciferous vegetables, particularly rich in sulfur.
In 2001, a team at Rutgers University in New Jersey summarised what diallyl sulfide from garlic does in metabolism. In rodents it inhibited the phase 1 enzyme CYP2E1, which among other things converts solvents and paracetamol into reactive products, and it could stimulate phase 2 enzymes.
The authors themselves emphasise that these effects occurred at amounts far above a normal diet. What this means for you: an interesting mechanism, but no evidence that garlic in food has the same effect.
Yang CS, Chhabra SK, Hong JY, Smith TJ. J Nutr. 2001;131(3s):1041S-1045S. DOI: 10.1093/jn/131.3.1041SA human study from Iran is interesting in this context, even if it should be read with caution.
In 2012, a team at Mashhad University of Medical Sciences led by Sina Kianoush treated workers from a battery factory with chronic lead exposure. One group received a standardised garlic preparation for four weeks, the other the drug D-penicillamine.
Blood lead levels fell in the garlic group from 426 to 347 micrograms per litre, and under D-penicillamine from 417 to 316, with no significant difference between the groups. What this means for you: garlic constituents appear to be able to play a role in the excretion of metals. Lead poisoning nevertheless always belongs in medical hands.
Kianoush S, Balali-Mood M, Mousavi SR et al. Basic Clin Pharmacol Toxicol. 2012;110(5):476-481. DOI: 10.1111/j.1742-7843.2011.00841.xGlutathione needs building blocks
Glutathione is the most important packaging molecule of phase 2. It consists of three amino acids: glutamate, cysteine and glycine. Sounds simple. But if one of the three building blocks runs short, production can stall like a bakery without flour.
In 2011, Rajagopal Sekhar and colleagues from Baylor College of Medicine in Houston compared eight older with eight younger people. The older participants had considerably less glycine, cysteine and glutathione in their red blood cells and more markers of oxidative stress.
After two weeks of cysteine and glycine supplementation, their glutathione rose by 94.6 percent. What this means for you: the supply of raw materials matters. However, the study was small and used supplements, not foods.
Sekhar RV, Patel SG, Guthikonda AP et al. Am J Clin Nutr. 2011;94(3):847-853. DOI: 10.3945/ajcn.110.003483Cysteine and methionine
Lentils, beans, chickpeas, oats, sunflower seeds, eggs. Methionine can be converted into cysteine in the body.
GlutathioneGlycine
Soy, lentils, pumpkin seeds, peanuts and gelatine. Glycine also serves directly as a coupling partner in phase 2.
Glutathione and conjugationSulfur
Garlic, onion, leek, broccoli, Brussels sprouts and cabbage. Supplies material for sulfation and sulfur metabolism.
SulfationTaurine
Found mainly in meat and poultry. The body can also make taurine itself from cysteine.
Bile acidsA practical tip for garlic: chop it and let it sit for ten minutes before it goes into the hot pan. Garlic also works with an enzyme, alliinase, which is lost through heat. This is common kitchen advice with plausible biochemistry.
The smell of garlic is not a flaw. It is the trace of a raw material your liver needs for packaging.
Detoxification sometimes doesn't begin with a supplement, but with an onion you don't leave out.
And now you know why sulfur and amino acids come up in every conversation about phase 2.
Is coffee good for the liver?
Maybe you drink your morning coffee with a faint sense of guilt. Somewhere you read that coffee is a poison you should cut back on. For the liver, large data collections paint a different picture.
In 2016, Oliver Kennedy and colleagues from the University of Southampton analysed five cohorts and four case-control studies with 432,133 participants and 1,990 cases of cirrhosis. Every increase of two cups of coffee per day was associated with a relative risk of 0.56 for cirrhosis.
This corresponds to a relative risk about 44 percent lower. What this means for you: coffee is among the foods with the clearest association with liver health. Cause and effect, however, cannot be reliably derived from observational data.
Kennedy OJ, Roderick P, Buchanan R et al. Aliment Pharmacol Ther. 2016;43(5):562-574. DOI: 10.1111/apt.13523In 2017, Robin Poole and colleagues from Southampton and Edinburgh summarised in the BMJ 201 meta-analyses of observational studies and 17 of intervention studies. Coffee was more often associated with benefit than with harm, and the most favourable associations appeared at three to four cups a day, including for liver disease.
At the same time, they found associations in pregnancy with low birth weight and miscarriage. What this means for you: coffee can be a friend to the liver for many people, but not for everyone and not in every phase of life.
Poole R, Kennedy OJ, Roderick P et al. BMJ. 2017;359:j5024. DOI: 10.1136/bmj.j5024Why might coffee do the liver good? Caffeine alone doesn't seem to be the whole explanation. Coffee is a mixture of hundreds of substances, including chlorogenic acids and roasting products. Some of them can activate Nrf2 in the lab, the same switch as sulforaphane.
In 2012, a team at the University of Vienna led by Doris Marko tested a special coffee blend in colon cancer cells and in 29 healthy volunteers. In cells, the activity of Nrf2 and GST rose. In the volunteers, who drank 750 millilitres a day for four weeks, Nrf2 activity in white blood cells rose on average.
The response, however, varied widely from person to person, apparently partly for genetic reasons. What this means for you: coffee might address phase 2, but your body responds individually.
Volz N, Boettler U, Winkler S et al. J Agric Food Chem. 2012;60(38):9631-9641. DOI: 10.1021/jf302258uAnd here a surprising circle closes. Caffeine itself is broken down in the liver via CYP1A2. A research group at the Fred Hutchinson Cancer Research Center in Seattle used exactly that as a measuring tool.
In 2000, 36 adults ate, one after another for six days each, a vegetable-free basic diet or a diet with cruciferous vegetables, alliums or apiaceous vegetables. Afterwards they received a test dose of caffeine, and CYP1A2 activity was calculated from their urine.
Cruciferous vegetables increased the activity, while apiaceous vegetables such as carrot, celery and parsnip lowered it. What this means for you: what's on your plate can help determine how quickly you break down your coffee.
Lampe JW, King IB, Li S et al. Carcinogenesis. 2000;21(6):1157-1162. DOI: 10.1093/carcin/21.6.1157Pregnancy: In two meta-analyses by Ling-Wei Chen and colleagues, each additional 100 milligrams of caffeine per day, roughly one cup, was associated with a 13 percent higher risk of low birth weight and a 7 percent higher risk of miscarriage. If you are pregnant or want to become pregnant, discuss your coffee intake with your doctor.
Reflux and a sensitive stomach: Coffee can worsen heartburn in some people. Then less is more, or a milder roast after meals.
Sleep, restlessness, heart rhythm: If you break down caffeine slowly, you feel it longer. Coffee in the afternoon can disturb sleep, and sleep is itself an important recovery period for metabolism.
Your morning coffee doesn't have to carry a guilty conscience. For many people, the data point more towards an ally of the liver.
But an ally only remains one if it suits your phase of life, your stomach and your sleep.
And now you know why I don't give a blanket yes or no on coffee, but ask about your everyday life.
Phase 3: What good is packaging if nothing ships out?
Imagine the packaging department working at full speed. Everything is neatly tied up. But the truck doesn't come. The parcels pile up at the loading dock. This is exactly what can happen when excretion stalls.
A large share of the packaged substances leaves the liver via the bile into the gut. That is where it is decided whether they actually leave the body. With sluggish digestion, gut bacteria can reopen some of the packages. The substances then return to the blood. This cycle between liver and gut is called the enterohepatic circulation. You'll find more on this in my article on the gut and elimination pathways.
Fibre
Legumes, flaxseed, oats, vegetables and berries add volume to stool and can bind bile acids.
Transport outBitter compounds
Chicory, radicchio, artichoke and dandelion can stimulate bile flow. More on this in the article on bitter compounds.
BileFluids
Water-soluble breakdown products leave the body via the kidneys. Drinking enough keeps this route open.
KidneyMovement
Walking after meals can stimulate bowel movement. Not a food, but an underrated part of phase 3.
RhythmMany people think only of the liver when it comes to detoxification. But the liver only packs. The gut has to ship.
A daily, soft bowel movement is therefore perhaps the least spectacular and at the same time one of the most important detox markers you can observe yourself.
And now you know why a broccoli smoothie does little if your digestion has been at a standstill for days.
The limits: grapefruit, medication and thyroid
If foods can influence enzymes, that works in both directions. That is exactly what makes them interesting. And that is exactly what demands respect. A food that changes an enzyme can also change how a medication is broken down.
In 2013, David Bailey, George Dresser and Malcolm Arnold from the Lawson Health Research Institute in Canada described how furanocoumarins from grapefruit inhibit the enzyme CYP3A4 in the intestinal wall. As a result, considerably more of certain medications may reach the blood than intended.
Affected drugs can include some statins, blood pressure medications, immunosuppressants and heart medications. What this means for you: if you take medication regularly, ask your pharmacist before drinking grapefruit juice. The same applies to pomelo and bitter orange.
Bailey DG, Dresser G, Arnold JMO. CMAJ. 2013;185(4):309-316. DOI: 10.1503/cmaj.120951Cruciferous vegetables can also influence medication levels, as the meta-analysis by Eagles showed. This mainly concerns drugs broken down via CYP1A2, for example theophylline or clozapine. What matters here is less the amount than the fluctuation. If you eat a similar amount of vegetables every day, your levels stay stable. If you suddenly start eating large amounts while on such medications, discuss it with your doctor.
In 2016, Peter Felker, Ronald Bunch and the endocrinologist Angela Leung from UCLA calculated how much goitrin and thiocyanate from cruciferous vegetables can reach the body. 194 micromoles of goitrin inhibited iodine uptake by the thyroid, 77 micromoles did not. Commercially available broccoli and kale contain less than 10 micromoles per 100 grams, Brussels sprouts and some collard-type greens considerably more.
Two of the authors work for a vegetable producer, which you should know when weighing the findings. What this means for you: in usual amounts the risk is considered low. It becomes relevant mainly with very large raw amounts combined with iodine deficiency.
Felker P, Bunch R, Leung AM. Nutr Rev. 2016;74(4):248-258. DOI: 10.1093/nutrit/nuv110A broccoli on your plate and a high-dose sulforaphane capsule differ in dose, accompanying compounds and effect on enzymes. The same applies to garlic in food and standardised garlic extracts, which can, for example, affect blood clotting.
My advice: start with foods. If you are considering a supplement, discuss it with your doctor, especially if you take medication, are pregnant or have surgery coming up.
That foods have limits is not an argument against them. It shows that they can actually make a biological difference.
What can be effective deserves attention. Not fear, but a clear view.
And now you know why I also look at your medication list with every dietary recommendation.
Three levers for your everyday life
You don't have to change everything at once. I'd rather recommend starting with a few habits that touch all three phases.
Three levers you can start with
- A handful of cruciferous vegetables every day, smartly prepared: rocket, cress, radishes raw, broccoli or Brussels sprouts only briefly steamed. Combine cooked vegetables with a little raw mustard or cress.
- Sulfur and building blocks in every main meal: onion, leek or garlic as a base, plus a portion of legumes, seeds or eggs. Let chopped garlic rest for ten minutes.
- Don't forget the outflow: fibre, something bitter before meals, enough water and a short walk after eating. Coffee can be part of it if it agrees with you and you are not pregnant.
If you want to see what gentle detoxification in everyday life without a cleanse can look like, read my article Gentle detox in everyday life. And if you want to know why I view juice cleanses and detox teas rather critically, you'll find the reasons in this article.
"Your liver doesn't need a rescuer from a tin. It needs a plate that helps out a little every day."
Shukri Jarmoukli, ViveCura BerlinIt's not about detoxing thoroughly once a year and forgetting about it the rest of the year. It's about feeling at home in your body again: clearer in your head, lighter after meals, more awake in the morning. If you understand how your liver works, you no longer have to chase after it. You can walk alongside it.
Frequently asked questions about foods for liver detoxification
Which foods may support the liver in detoxification?
The best studied are cruciferous vegetables such as broccoli, Brussels sprouts, rocket and cabbage, sulfur-rich alliums such as garlic and onion, coffee and fibre-rich plant foods. They do not deliver detox at the push of a button. They provide building blocks and signalling compounds for the liver's enzymes. A meta-analysis of 23 human dietary studies showed that cruciferous vegetables can raise the activity of CYP1A2 by about 20 to 40 percent and of GST-alpha by about 15 to 35 percent. What matters is regularity in everyday life, not a single cleanse.
What is the difference between phase 1 and phase 2 of detoxification?
In phase 1, cytochrome P450 enzymes change a substance chemically, mostly through oxidation. This sometimes creates more reactive intermediates. In phase 2, these intermediates are bound to the body's own molecules such as glutathione, glucuronic acid, sulfate or glycine, which makes them water-soluble. Excretion via bile, gut and kidneys follows, often called phase 3. It is helpful when phase 2 can keep pace with phase 1.
Is coffee good for the liver?
Observational studies point in that direction. In a meta-analysis with more than 432,000 participants, every increase of two cups per day was associated with a 44 percent lower relative risk of cirrhosis. A large umbrella review in the BMJ found the most favourable associations at around three to four cups a day. These are associations, not proof of cause and effect. In pregnancy, with reflux, heart rhythm disorders or sleep problems, the balance looks different.
What can sulforaphane do in detoxification?
Sulforaphane forms from glucoraphanin when broccoli is chopped or chewed and the plant's own enzyme myrosinase gets to work. It can activate the Nrf2 switch, which stimulates the production of protective and phase 2 enzymes such as glutathione S-transferases. In a randomised trial with 291 people in China, a broccoli sprout beverage increased the excretion of benzene breakdown products by 61 percent. This was a concentrated beverage, not a normal portion of vegetables.
Should I eat broccoli raw or cooked?
For sulforaphane, raw or only briefly cooked broccoli is more favourable. In a crossover study with 12 men, the bioavailability of isothiocyanates from fresh broccoli was about three times higher than from steamed broccoli, because heat destroys myrosinase. A practical compromise is brief steaming, or combining cooked cruciferous vegetables with a little raw mustard, rocket or cress. If raw vegetables do not agree with you, cooked is better than none at all.
What does garlic do for detoxification?
Garlic provides sulfur-containing compounds. In animal studies, constituents such as diallyl sulfide inhibit the phase 1 enzyme CYP2E1 and can stimulate phase 2 enzymes, though at amounts far above a normal diet. In a randomised trial with 117 workers with chronic lead exposure, blood lead levels fell under a standardised garlic preparation similarly to D-penicillamine. That was a preparation in a high-risk group and does not replace medical treatment of poisoning.
Why is grapefruit a problem with medication?
Grapefruit contains furanocoumarins, which can inhibit the enzyme CYP3A4 in the intestinal wall. As a result, considerably more of some medications may reach the bloodstream than intended. Affected drugs can include some statins, blood pressure medications, immunosuppressants and heart medications. If you take medication regularly, ask your pharmacist or doctor before eating grapefruit. The same applies to pomelo and bitter orange.
Do cruciferous vegetables harm the thyroid?
In usual amounts, very likely not. The breakdown product goitrin can be critical: 194 micromoles inhibited iodine uptake by the thyroid, 77 micromoles did not. Commercially available broccoli and kale contain less than 10 micromoles per 100 grams. Brussels sprouts and collard-type greens can contain more. This becomes relevant mainly with very large raw amounts combined with iodine deficiency.
Do I need detox supplements if I eat well?
In most cases, no. The liver detoxifies constantly, and the studies most relevant to everyday life examine foods and dietary patterns. Concentrated supplements can intervene more strongly in enzyme systems and may therefore also change medication levels. If you are considering a supplement, the decision belongs in a conversation with your doctor, taking your medications and lab values into account.
Which plant foods provide building blocks for glutathione?
Glutathione consists of glutamate, cysteine and glycine. Cysteine and methionine are found, for example, in legumes, oats, sunflower and pumpkin seeds, and in eggs. Glycine comes from soy, lentils, pumpkin seeds and gelatine, among others. Sulfur also comes from alliums and cruciferous vegetables. In a small study with older adults, glutathione rose by 94.6 percent after two weeks of cysteine and glycine supplementation.
Further reading in the ViveCura guide
These articles connect directly to this topic.
Detoxification
Liver, gut and excretion without myths
You are herePhase 1 and 2
The biochemistry of liver detoxification
Glutathione
The master antioxidant of the cell
Bitter compounds
Dandelion, artichoke and bile
Gut and elimination
The enterohepatic circulation explained
Liver detox
What a liver needs for its work
Gentle detox
Relief in everyday life without a cleanse
Detox cleanses
Juice cleanses and detox teas critically reviewed
Alcohol and the liver
What happens as each glass is broken down
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