Major interaction on record — check this product against your medications before combining. Based on 2 of 3 ingredients. Check your meds →
Dietary supplement

Carb Blocker Ingredients & Drug Interactions

by Nutrilite

Carb Blocker label
See full label image
Tablet Or Pill Category: Botanical
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 23, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Carb Blocker against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Major

Carb Blocker is a dietary supplement by Nutrilite with 3 active ingredients. Its ingredients are commonly taken for menopause symptoms (hot flashes), heart and cholesterol health, bone health.Based on those ingredients, 788 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Soybean extract, Parsley concentrate. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Carb Blocker by Nutrilite

Ask about any prescription or over-the-counter medication and we check it for interactions with Carb Blocker by Nutrilite — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Carb Blocker by Nutrilite

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 11, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 3 of its 3 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Nutrilite Carb Blocker contains three active ingredients. Soybean extract and parsley concentrate are the ones we have data on; kidney bean extract is the third, but we don't hold interaction information for it.

The product also contains several inactive ingredients (fillers and binders like microcrystalline cellulose, stearic acid, and carnauba wax) that help hold the tablet together.

Does it work?

Moderate evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: Inhibit digestion of simple sugars and complex carbohydrates.
  • We looked for evidence on: Diabetes, Obesity, Metabolic syndrome, Hyperlipidemia, Blood sugar control, Glycemic management — and 2 related terms.
  • The strongest evidence on file: Soy is rated "Possibly Effective" for Diabetes (Natural Medicines).
  • Also on file: Soy is rated "Possibly Effective" for Hyperlipidemia, Metabolic syndrome.
  • Also on file: Parsley is rated "Insufficient Reliable Evidence To Rate" for Diabetes.

For soybean extract, the data shows it may be possibly effective for lowering cholesterol (hyperlipidemia), managing blood sugar in diabetes, reducing blood pressure in people with hypertension, strengthening bone (osteoporosis), and easing diarrhea. For parsley concentrate, we don't have enough reliable evidence to rate how well it works for the conditions listed—that includes urinary tract infections, dark skin patches (melasma), joint pain (osteoarthritis), and skin cancer prevention.

We hold no effectiveness data for kidney bean extract.

The evidence, ingredient by ingredient Soy Parsley

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Soybean extract from whole foods is generally well tolerated, though concentrated isoflavone supplements warrant more caution. Common side effects include bloating, constipation, diarrhea, and nausea.

Allergic reactions (rash, itching) can occur in some people. Parsley concentrate is safe at food amounts but may not be safe in large doses.

At very high doses, it can cause serious effects like low blood pressure, kidney problems, or blood disorders—these are rare but documented. Both ingredients can trigger allergies or asthma in sensitive people.

For pregnancy, soybean extract is rated likely safe to possibly unsafe (mixed data), so talk with your doctor. Parsley is rated likely unsafe in pregnancy and should be avoided in medicinal amounts.

For breastfeeding, soybean in food amounts is likely safe, but concentrated supplements haven't been well studied; parsley data isn't on file for lactation.

Side effects, ingredient by ingredient Soy Parsley

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 2 of the 2 matched ingredients can interact with medications — Parsley, Soy.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications.
  • For scale: 788 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Stop here if you take an MAOI antidepressant—this is a Major interaction. Before starting, double-check with your pharmacist if you're on blood pressure drugs, diabetes medication, blood thinners (especially warfarin), thyroid medication, hormone replacement therapy, water pills, caffeine supplements in high amounts, the sedative pentobarbital, the transplant drug sirolimus, or aspirin—especially if you have a parsley allergy.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence for its stated purpose. Major medication interactions have been identified, and safety information is well characterized.

If you take an MAOI antidepressant or blood pressure drug, this product is not for you. Anyone on blood thinners, diabetes medication, thyroid medication, or hormone replacement therapy should check with their pharmacist first.

This product is not advised in pregnancy or in large amounts while breastfeeding. Talk to your pharmacist about your exact medications before you start.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 2 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Apr 24, 2025.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Carb Blocker, straight from the product label.

Brand Nutrilite
Barcode (UPC) 100193
Net contents 90 Tablet(s)
Market status On market
Date entered into DSLD Apr 24, 2025
DSLD ID 328144
Product type Botanical
Supplement form Tablet Or Pill
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Halal
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Carb Blocker by Nutrilite, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Tablet(s)
Maximum serving Sizes:
3 Tablet(s)
Servings per container
30
UPC/BARCODE
100193
IngredientAmount% DV
Kidney Bean Extract500 mg--
Soybean extract300 mg--
Parsley concentrate30 mg--

Other ingredients: Microcrystalline Cellulose, Stearic Acid, Acacia, Silicon Dioxide, Sodium Carboxymethylcellulose, Methylcellulose, Glycerin, Carnauba Wax

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Formulation

This unique Nutrilite blend is designed to inhibit the digestion of both simple sugars and complex carbohydrates. Laboratory tests show that the key ingredients in Carb Blocker have a carbohydrate blocking effect. These results suggest that a similar action in humans may help block up to 500 calories when consumed with a high carbohydrate meal.

No artificial flavors, colors or preservatives added.

Block up to 500 carbs per meal

General Statements

Anyone on a calorie-restricted diet should take a daily multivitamin multimineral supplement to ensure nutritional adequacy.

Precautions

Pregnant or lactating women, or anyone with a medical condition, including diabetes and hypoglycemia, should consult with a physician before using this product.

Do not exceed 9 tablets per day.

Exclusively from Amway

Storage

Keep bottle tightly closed. Store in a cool, dry place.

FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

1-3 tablets per meal

Suggested use: Adults take one toe three tablets with a carbohydrate-containing meal. Do not exceed 9 tablets per day.

Seals/Symbols

Quality you can trust since 1934

Crescent M (Halal)

FDA Disclaimer Statement

This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Brand IP Statement(s)

Copyright Alticor Inc.

Formula

Crescent M (Halal)

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Carb Blocker by Nutrilite label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Carb Blocker label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Carb Blocker by Nutrilite

These are the 3 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Tablet(s) Dosage formTablet Or Pill Servings per container30 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Kidney Bean Extract

500 mg per serving

Soybean extract

Interacts with
611 drugs
300 mg per serving

Soy is a nutritious bean that is a staple food and a popular source of plant protein and isoflavones. Eating soy foods as part of a balanced diet is g...

Soybean extract monograph & interactions

Parsley concentrate

Interacts with
443 drugs
30 mg per serving

Parsley is a popular culinary herb that is safe to eat in normal food amounts and is a good source of vitamins K and C. It is traditionally used as a...

Parsley concentrate monograph & interactions

Other (inactive) ingredients: Microcrystalline Cellulose, Stearic Acid, Acacia, Silicon Dioxide, Sodium Carboxymethylcellulose, Methylcellulose, Glycerin, Carnauba Wax. These complete the product’s ingredient list but are not active constituents.

Interaction report

Carb Blocker by Nutrilite Drug Interactions

Want to check YOUR meds against Carb Blocker?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
788Drugs
9 Major 557 Moderate 222 Minor

Ingredients driving the most interactions

Soybean extract 611
Parsley concentrate 443

Individual Drug Interactions

The ingredients in Carb Blocker interact with 788 drugs. Click any drug to see the details.

2 of the 3 ingredients in Carb Blocker interact with drugs. Each result below shows which ingredient is responsible. Soybean extract Parsley concentrate

Each ingredient & the kinds of drugs it affects

For each ingredient in Carb Blocker with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Soybean extract12 drug types · 611 drugs

Monoamine Oxidase Inhibitors (Maois)

Taking soy products containing high amounts of tyramine along with MAOIs can increase the risk of hypertensive crisis.
Fermented soy products such as tofu and soy sauce contain tyramine, a naturally occurring chemical that affects blood pressure regulation. The metabolism of tyramine is decreased by MAOIs. Consuming more than 6 mg of tyramine while taking an MAOI can increase the risk of hypertensive crisis. The amount of tyramine in fermented soy products is usually less than 0.6 mg per serving; however, there can be significant variation depending on the specific product used, storage conditions, and length of storage. Storing one brand of tofu for a week can increase tyramine content from 0.23 mg to 4.8 mg per serving. Advise patients taking MAOIs to avoid fermented soy products that contain high amounts of tyramine.

Likelihood Likely Evidence C
Antidiabetes Drugs

Soy can lower blood glucose and have additive effects with antidiabetes drugs.
Clinical research shows that whole soy diets and soy-based meals reduce fasting glucose levels in diabetic and non-diabetic individuals. Also, individuals following a soy-based meal replacement plan seem to require lower doses of sulfonylureas and metformin to manage blood glucose levels when compared with individuals following a diet plan recommended by the American Diabetes Association.

Likelihood Possible Evidence A
Antihypertensive Drugs

Theoretically soy protein may have additive effects with antihypertensive drugs and increase the risk of hypotension.
Although some contradictory research exists, most clinical evidence suggests that consuming soy protein modestly reduces systolic and diastolic blood pressure in individuals with prehypertension or hypertension.

Likelihood Possible Evidence A
Caffeine

Theoretically, soy might reduce the clearance of caffeine.
Soy contains genistein. Taking genistein 1 gram daily for 14 days seems to inhibit caffeine clearance and metabolism in healthy females. This effect has been attributed to inhibition of the cytochrome P450 1A2 (CYP1A2) enzyme, which is involved in caffeine metabolism. It is unclear if this effect occurs with the lower amounts of genistein found in soy.

Likelihood Possible Evidence D
Diuretic Drugs

Theoretically, soy might have additive effects when used with diuretic drugs.
Animal research suggests that genistein, a soy isoflavone, increases diuresis within 6 hours of subcutaneous administration in rats. The effects seem to be similar to those of furosemide. This effect has not been reported in humans.

Likelihood Possible Evidence D
Estrogens

Theoretically, soy might competitively inhibit the effects of estrogen replacement therapy.
Soy contains phytoestrogens and has been shown to have estrogenic activity in some patients. Although this has not been demonstrated in humans, theoretically, concomitant use of soy with estrogen replacement therapy might reduce the effects of the estrogen replacement therapy.

Likelihood Possible Evidence D
Levothyroxine (Synthroid, Others)

Soy products might reduce the absorption of levothyroxine in some patients.
Preliminary clinical research and a case report suggest that soy-based formulas inhibit the absorption of levothyroxine in infants with congenital hypothyroidism. A levothyroxine dosage increase may be needed for infants with congenital hypothyroidism while using soy-based formulas, and the dose may need to be reduced when soy-based formulas are no longer administered. However, in postmenopausal adults, clinical research shows that taking a single dose of soy extract containing isoflavones 60 mg along with levothyroxine does not affect the oral bioavailability of levothyroxine.

Likelihood Possible Evidence B
Progesterone

Theoretically, combining soy isoflavones with transdermal progesterone may worsen bone density.
Clinical research suggests that significant bone loss may occur in females with osteoporosis who receive a combination of transdermal progesterone with soy milk containing isoflavones when compared with placebo, soy milk alone, or progesterone alone.

Likelihood Possible Evidence A
Tamoxifen (Nolvadex)

Theoretically, estrogenic soy isoflavones might alter the effects of tamoxifen.
Laboratory research suggests that genistein and daidzen, isoflavones from soy, can antagonize the antitumor effects of tamoxifen under some circumstances; however, soy isoflavones might have different effects when used at different doses. A relatively low in vitro concentration of soy isoflavones such as 1 microM/L seems to interfere with tamoxifen, whereas high in vitro concentrations such as those >10 microM/L might actually enhance tamoxifen effects. People on a high-soy diet have soy isoflavones levels ranging from 0.1-6 microM/L. Until more is known, advise patients taking tamoxifen to avoid therapeutic use of soy products.

Likelihood Possible Evidence B
Warfarin (Coumadin)

Theoretically, soy might interfere with the effects of warfarin.
Soy milk has been reported to decrease the international normalized ratio (INR) in a patient taking warfarin. The mechanism of this interaction is not known. However, animal and in vitro research suggests that soy may also inhibit platelet aggregation. Dosing adjustments for warfarin may be necessary.

Likelihood Possible Evidence D
Antibiotic Drugs

Theoretically, antibiotics may decrease the activity of soy isoflavones.
Intestinal bacteria are responsible in part for converting soy isoflavones into their active forms. Antibiotics may decrease the amount of intestinal bacteria and decrease its ability to convert isoflavones.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Soy might modestly induce CYP2C9 enzymes. However, this effect does not seem to be clinically significant.
In vitro research suggests that an unhydrolyzed soy extract might induce CYP2C9. However, the significance of this interaction is likely minimal. In healthy females taking a specific extract of soy (Genistein Soy Complex, Source Naturals), blood levels of losartan, a CYP2C9 substrate, were not significantly affected.

Likelihood Unlikely Evidence D
Soybean extract full monograph & interactions

Parsley concentrate8 drug types · 443 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, parsley might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
Animal research suggests that parsley has antiplatelet effects.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, parsley might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Animal research suggests that parsley might decrease blood glucose. Monitor blood glucose levels closely. Dose adjustments might be necessary.

Likelihood Possible Evidence D
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, parsley might increase serum levels of CYP1A2 substrates.
Laboratory research suggests that parsley can inhibit CYP1A2.

Likelihood Possible Evidence D
Diuretic Drugs

Theoretically, parsley might enhance or interfere with the effects of diuretic drugs.
Animal research suggests that parsley seed extract increases urine elimination. Parsley leaf and root might also interfere with diuretic therapy due their purported aquaretic effects.

Likelihood Possible Evidence D
Pentobarbital (Nembutal)

Theoretically, parsley might increase the duration of pentobarbital effects.
Animal research suggests that parsley juice prolongs the action of pentobarbital, perhaps by decreasing cytochrome P450 levels. It is not known if this occurs in humans or if this applies to other barbiturates or sedatives.

Likelihood Possible Evidence D
Sirolimus (Rapamune)

Theoretically, large quantities of parsley might increase sirolimus levels.
In one case report, an adult female with a history of kidney transplant presented with elevated blood sirolimus levels, approximately 4-7 times greater than previous measures, after daily consumption of a juice containing approximately 30 grams of parsley for 7 days. Sirolimus levels returned to normal a week after the parsley juice was discontinued.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, large amounts of parsley leaf and root might decrease the effects of warfarin.
Parlsey contains vitamin K.

Likelihood Possible Evidence D
Aspirin

Theoretically, aspirin might increase the severity of allergic reactions to parsley.
In one case, severe urticaria and swelling were reported after taking aspirin with parsley in an individual with a known mild parsley allergy.

Likelihood Unlikely Evidence D
Parsley concentrate full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Carb Blocker, from the product label.

Nutrilite

See all Nutrilite products
Name
Amway Corp.
City
Ada
State
MI
ZipCode
49355
Phone Number
1-800-253-6500
Web Address
Amway.com/Nutrilite
Pharmacist Counseling Corner

Carb Blocker by Nutrilite: Common Questions

Does Carb Blocker by Nutrilite interact with any medications?
Yes. Based on its ingredients, Carb Blocker has a known interaction with 788 medications, including 9 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Carb Blocker contains 3 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
What does this product actually do?
The soybean extract and parsley concentrate in this product are intended to help block or slow the absorption of carbohydrates from food. Soybean extract has some evidence it may help with cholesterol, blood sugar control, and blood pressure; parsley's effectiveness for any specific condition isn't well established in the data we hold.
Is it safe to take while pregnant?
The safety data is mixed. Soybean extract is rated likely safe to possibly unsafe during pregnancy—there's conflicting information. Parsley concentrate is rated likely unsafe and should be avoided in medicinal amounts during pregnancy. Talk with your doctor before taking this product if you're pregnant or planning to become pregnant.
Can I take this while breastfeeding?
Soybean in food amounts is likely safe while breastfeeding, but concentrated supplements haven't been well studied. We don't have safety data on file for parsley during breastfeeding. It's best to check with your pharmacist or doctor before using this product while nursing.
What side effects might I notice?
The most common are bloating, constipation, diarrhea, and nausea from the soybean extract. Allergic reactions like rash or itching can happen in some people. At very high doses, parsley can cause serious effects, but the amounts in this product are not typically that high.
Do I need to worry about my thyroid medication?
Yes. Soybean extract may reduce how much thyroid medication (levothyroxine) your body absorbs, potentially making it less effective. Your doctor may need to adjust your dose. Check with your pharmacist before taking this product if you're on thyroid medication.
I'm on a water pill for blood pressure—is this okay?
Both soybean extract and parsley can theoretically add to the effects of diuretics (water pills) and may affect your blood pressure or electrolytes. Talk with your pharmacist or doctor before starting this product if you're on a diuretic.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Carb Blocker label
Go deeper

The Full Monographs Behind Carb Blocker’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Soy

Interacts with 611 drugs

Soy is a nutritious bean that is a staple food and a popular source of plant protein and isoflavones. Eating soy foods as part of a balanced diet is generally considered safe for most people...

Read the full Soy monograph → Herb & supplement monograph

Parsley

Interacts with 443 drugs

Parsley is a popular culinary herb that is safe to eat in normal food amounts and is a good source of vitamins K and C. It is traditionally used as a diuretic and for digestion, but solid hu...

Read the full Parsley monograph →
Sources

Sources & How We Checked

Carb Blocker's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 109 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Soy 88 references
  1. Franke AA, Custer LJ, Tanaka Y. Isoflavones in human breast milk and other biological fluids. Am J Clin Nutr 1998;68:1466-73. PubMed
  2. Albertazzi P, Pansini F, Bonaccorsi G, et al. The effect of dietary soy supplementation on hot flushes. Obstet Gynecol 1998;91:6-11. PubMed
  3. Lu LJ, Anderson KE, Grady JJ, et al. Decreased ovarian hormones during a soya diet: implications for breast cancer prevention. Cancer Res 2000;60:4112-21.
  4. Pino AM, Valladares LE, Palma MA, et al. Dietary isoflavones affect sex hormone-binding globulin levels in postmenopausal women. J Clin Endocrinol Metab 2000;85:2797-800. DOI
  5. Nisley N, Klepser T. Phytoestrogens for the prevention and treatment of osteoporosis. Alt Med Alert 1999 Dec;138-42.
  6. McMichael-Phillips DF, Harding C, Morton M, et al. Effects of soy-protein supplementation on epithelial proliferation in the histologically normal human breast. Am J Clin Nutr 1998;68:1431S-5S. PubMed
  7. Petrakis NL, Barnes S, King EB, et al. Stimulatory influence of soy protein isolate on breast secretion in pre- and postmenopausal women. Cancer Epidemiol Biomarkers Prev 1996;5:785-94.
  8. Baird DD, Umbach DM, Lansdell L, et al. Dietary intervention study to assess estrogenicity of dietary soy among postmenopausal women. J Clin Endocrinol Metab 1995;80:1685-90. DOI
  9. Duncan AM, Underhill KE, Xu X, et al. Modest hormonal effects of soy isoflavones in postmenopausal women. J Clin Endocrinol Metab 1999;84:3479-84. PubMed
  10. Ginsburg J, Prelevic GM. Lack of significant hormonal effects and controlled trials of phyto-oestrogens. Lancet 2000;355:163-4. PubMed
  11. Anthony MS. Soy and cardiovascular disease: Cholesterol lowering and beyond. J Nutr 2000;130:662S-3S. PubMed
  12. Hargreaves DF, Potten CS, Harding C, et al. Two-week dietary soy supplementation has an estrogenic effect on normal premenopausal breast. J Clin Endocrinol Metab 1999;84:4017-24. DOI
  13. Lamartiniere CA. Protection against breast cancer with genistein: a component of soy. Am J Clin Nutr 2000;71:1705S-7S. PubMed
  14. Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?CFRPart=182
  15. Codina R, Ardusso L, Lockey RF, et al. Sensitization to soybean hull allergens in subjects exposed to different levels of soybean dust inhalation in Argentina. J Allergy Clin Immunol 2000;105:570-6. PubMed
  16. Anto JM, Sunyer J, Rodriguez-Roisin R, et al. Community outbreaks of asthma associated with inhalation of soybean dust. Toxicoepidemiological Committee. N Engl J Med 1989;320:1097-1102. PubMed
  17. White MC, Etzel RA, Olson DR, Goldstein IF. Re-examination of epidemic asthma in New Orleans, Louisianna, in relation to the presence of soy at the harbor. Am J Epidemiol 1997;145:432-8.
  18. Murkies A, Dalais FS, Briganti EM, et al. Phytoestrogens and breast cancer in postmenopausal women: a case control study. Menopause 2000;7:289-96. PubMed
  19. Setchell KD, Cassidy A. Dietary isoflavones: biological effects and relevance to human health. J Nutr 1999;129:758S-67S. PubMed
  20. Teixeira SR, Potter SM, Weigel R, et al. Effects of feeding 4 levels of soy protein for 3 and 6 wk on blood lipids and apolipoproteins in moderately hypercholesterolemic men. Am J Clin Nutr 2000;71:1077-84. PubMed
  21. White LR, Petrovitch H, Ross GW, et al. Brain aging and midlife tofu consumption. J Am Coll Nutr 2000;19:242-55. PubMed
  22. Grodstein F, Mayeux R, Stampfer MJ. Tofu and cognitive function: food for thought. J Am Coll Nutr 2000;19:207-9. PubMed
  23. Divi RL, Chang HC, Doerge DR. Anti-thyroid isoflavones from soybean: isolation, characterization, and mechanisms of action. Biochem Pharmacol 1997;54:1087-96. PubMed
  24. de Lemos ML. Effects of soy phytoestrogens genistein and daidzein on breast cancer growth. Ann Pharmacother 2001;35:1118-21. PubMed
  25. Strom BL, Schinnar R, Ziegler EE, et al. Exposure to soy-based formula in infancy and endocrinological and reproductive outcomes in young adulthood. JAMA 2001;286:807-14. PubMed
  26. Goodman MT, Wilkens LR, Hankin JH, et al. Association of soy and fiber consumption with the risk of endometrial cancer. Am J Epidemiol 1997;146:294-306. PubMed
  27. Wu AH, Yang D, Pike MC. A meta-analysis of soyfoods and risk of stomach cancer: the problem of potential confounders. Cancer Epidemiol Biomarkers Prev 2000;9:1051-8.
  28. Ji BT, Chow WH, Yang G, et al. Correspondence re: AH Wu et al, A meta-analysis of soyfoods and risk of stomach cancer: the problem of potential confounders. Cancer Epidemiol Biomarkers Prev 2001;10:570.
  29. Foth D, Cline JM. Effects of mammalian and plant estrogens on mammary glands and uteri of macaques. Am J Clin Nutr 1998;68:1413S-7S. PubMed
  30. Duncan AM, Merz BE, Xu X, et al. Soy isoflavones exert modest hormonal effects in premenopausal women. J Clin Endocrinol Metab 1999;84:192-7. DOI
  31. Morito K, Hirose T, Kinjo J, et al. Interaction of phytoestrogens with estrogen receptors alpha and beta. Biol Pharm Bull 2001;24:351-6. PubMed
  32. Persky VW, Turyk ME, Wang L, et al. Effect of soy protein on endogenous hormones in postmenopausal women. Am J Clin Nutr 2002;75:145-53. PubMed
  33. Ju YH, Doerge DR, Allred KF, et al. Dietary Genistein Negates the Inhibitory Effect of Tamoxifen on Growth of Estrogen-dependent Human Breast Cancer (MCF-7) Cells Implanted in Athymic Mice. Cancer Res 2002;62:2474-7 .
  34. Cambria-Kiely JA. Effect of soy milk on warfarin efficacy. Ann Pharmacother 2002;36:1893-6.. PubMed
  35. Ziegler RG, Hoover RN, Pike MC, et al. Migration patterns and breast cancer risk in Asian-American women. J Natl Cancer Inst 1993;85:1819-27.. PubMed
  36. Brown BD, Thomas W, Hutchins A, et al. Types of dietary fat and soy minimally affect hormones and biomarkers associated with breast cancer risk in premenopausal women. Nutr Cancer 2002;43:22-30.. PubMed
  37. Sun CL, Yuan JM, Arakawa K, et al. Dietary soy and increased risk of bladder cancer: the Singapore Chinese Health Study. Cancer Epidemiol Biomarkers Prev 2002;11:1674-7.
  38. Balk JL, Whiteside DA, Naus G, et al. A pilot study of the effects of phytoestrogen supplementation on postmenopausal endometrium. J Soc Gynecol Investig 2002;9:238-42.. DOI
  39. Horn-Ross PL, John EM, Canchola AJ, et al. Phytoestrogen intake and endometrial cancer risk. J Natl Cancer Inst 2003;95:1158-64.. PubMed
  40. Kumar NB, Cantor A, Allen K et al. The specific role of isoflavones in reducing prostate cancer risk. Prostate 2004;59:141-7. PubMed
  41. Chen A, Rogan WJ. Isoflavones in soy infant formula: a review of evidence for endocrine and other activity in infants. Annu Rev Nutr 2004;24:33-54. PubMed
  42. Chen YM, Ho SC, Lam SS, et al. Soy isoflavones have a favorable effect on bone loss in Chinese postmenopausal women with lower bone mass: a double-blind, randomized, controlled trial. J Clin Endocrinol Metab 2003;88:4740-7. PubMed
  43. Unfer V, Casini ML, Costabile L, et al. Endometrial effects of long-term treatment with phytoestrogens: a randomized, double-blind, placebo-controlled study. Fertil Steril 2004;82:145-8. PubMed
  44. Bruce B, Messina M, Spiller G. Isoflavone supplements do not affect thyroid function in iodine-replete postmemopausal women. J Med Food 2003;6:309-16.
  45. He J, Gu D, Wu X, et al. Effect of soybean protein on blood pressure: A randomized, controlled trial. Ann Intern Med 2005;143:1-9. PubMed
  46. Kaari C, Haidar MA, Junior JMS, et al. Randomized clinical trial comparing conjugated equine estrogens and isoflavones in postmenopausal women: a pilot study. Maturitas 2006;53:49-58. PubMed
  47. Sacks FM, Lichtenstein A, Van Horn L, et al. Soy protein, isoflavones, and cardiovascular health. An American Heart Association Science Advisory for Professionals from the Nutrition Committee. Circulation 2006;113:1034-44. PubMed
  48. Jones JL, Daley BJ, Enderson BL, et al. Genistein inhibits tamoxifen effects on cell proliferation and cell cycle arrest in T47D breast cancer cells. Am Surg 2002;68:575-7. DOI
  49. Shulman KI, Walker SE. Refining the MAOI diet: tyramine content of pizzas and soy products. J Clin Psychiatry 1999;60:191-3. DOI
  50. Gardner DM, Shulman KI, Walker SE, Tailor SA. The making of a user friendly MAOI diet. J Clin Psychiatry 1996;57:99-104.
  51. Walker SE, Shulman KI, Tailor SA, Gardner D. Tyramine content of previously restricted foods in monoamine oxidase inhibitor diets. J Clin Psychopharmacol 1996;16:383-8. PubMed
  52. Krebs EE, Ensrud KE, MacDonald R, Wilt TJ. Phytoestrogens for treatment of menopausal symptoms: a systematic review. Obstet Gynecol 2004;104:824-36. PubMed
  53. Wang G, Xiao CQ, Li Z, et al. Effect of soy extract administration on losartan pharmacokinetics in healthy female volunteers. Ann Pharmacother 2009;43:1045-9. PubMed
  54. Jabbar MA, Larrea J, Shaw RA. Abnormal thyroid function tests in infants with congenital hypothyroidism: the influence of soy-based formula. J Am Coll Nutr. 1997;16(3):280-2. PubMed
  55. Conrad SC, Chiu H, Silverman BL. Soy formula complicates management of congenital hypothyroidism. Arch Dis Child. 2004;89(1):37-40. PubMed
  56. Chen, Y., Xiao, C. Q., He, Y. J., Chen, B. L., Wang, G., Zhou, G., Zhang, W., Tan, Z. R., Cao, S., Wang, L. P., and Zhou, H. H. Genistein alters caffeine exposure in healthy female volunteers. Eur.J Clin.Pharmacol. 2011;67(4):347-353. PubMed
  57. Whelan, A. M., Jurgens, T. M., and Naylor, H. Herbs, vitamins and minerals in the treatment of premenstrual syndrome: a systematic review. Can.J.Clin.Pharmacol. 2009;16(3):e407-e429.
  58. Lydeking-Olsen, E., Beck-Jensen, J. E., Setchell, K. D., and Holm-Jensen, T. Soymilk or progesterone for prevention of bone loss--a 2 year randomized, placebo-controlled trial. Eur.J Nutr. 2004;43(4):246-257. PubMed
  59. Hill, D. J., Heine, R. G., Cameron, D. J., Francis, D. E., and Bines, J. E. The natural history of intolerance to soy and extensively hydrolyzed formula in infants with multiple food protein intolerance. J.Pediatr. 1999;135(1):118-121. PubMed
  60. Fitzpatrick, M. Soy formulas and the effects of isoflavones on the thyroid. N.Z.Med J 2-11-2000;113(1103):24-26.
  61. Li, Z., Hong, K., Saltsman, P., DeShields, S., Bellman, M., Thames, G., Liu, Y., Wang, H. J., Elashoff, R., and Heber, D. Long-term efficacy of soy-based meal replacements vs an individualized diet plan in obese type II DM patients: relative effects on w
  62. Post-Skagegard, M., Vessby, B., and Karlstrom, B. Glucose and insulin responses in healthy women after intake of composite meals containing cod-, milk-, and soy protein. Eur J Clin Nutr 2006;60(8):949-954. PubMed
  63. Mclachlan, J. A., Simpson, E., and Martin, M. Endocrine disrupters and female reproductive health. Best.Pract Res Clin Endocrinol.Metab 2006;20(1):63-75. PubMed
  64. Messina, M. and Redmond, G. Effects of soy protein and soybean isoflavones on thyroid function in healthy adults and hypothyroid patients: a review of the relevant literature. Thyroid 2006;16(3):249-258. PubMed
  65. Rozman, K. K., Bhatia, J., Calafat, A. M., Chambers, C., Culty, M., Etzel, R. A., Flaws, J. A., Hansen, D. K., Hoyer, P. B., Jeffery, E. H., Kesner, J. S., Marty, S., Thomas, J. A., and Umbach, D. NTP-CERHR expert panel report on the reproductive and dev
  66. Azadbakht, L., Kimiagar, M., Mehrabi, Y., Esmaillzadeh, A., Padyab, M., Hu, F. B., and Willett, W. C. Soy inclusion in the diet improves features of the metabolic syndrome: a randomized crossover study in postmenopausal women. Am J Clin Nutr 2007;85(3):7 PubMed
  67. Berseth, C. L., Johnston, W. H., Stolz, S. I., Harris, C. L., and Mitmesser, S. H. Clinical response to 2 commonly used switch formulas occurs within 1 day. Clin.Pediatr.(Phila) 2009;48(1):58-65. PubMed
  68. Altorf-van der Kuil, W., Engberink, M. F., Brink, E. J., van Baak, M. A., Bakker, S. J., Navis, G., van, 't, V, and Geleijnse, J. M. Dietary protein and blood pressure: a systematic review. PLoS.One. 2010;5(8):e12102. PubMed
  69. Clement, Y. N., Onakpoya, I., Hung, S. K., and Ernst, E. Effects of herbal and dietary supplements on cognition in menopause: a systematic review. Maturitas 2011;68(3):256-263. PubMed
  70. Liu, Z. M., Chen, Y. M., and Ho, S. C. Effects of soy intake on glycemic control: a meta-analysis of randomized controlled trials. Am.J.Clin.Nutr. 2011;93(5):1092-1101. PubMed
  71. Iyngkaran, N., Yadav, M., Looi, L. M., Boey, C. G., Lam, K. L., Balabaskaran, S., and Puthucheary, S. D. Effect of soy protein on the small bowel mucosa of young infants recovering from acute gastroenteritis. J Pediatr.Gastroenterol.Nutr 1988;7(1):68-75. DOI
  72. Freni-Titulaer, L. W., Cordero, J. F., Haddock, L., Lebron, G., Martinez, R., and Mills, J. L. Premature thelarche in Puerto Rico. A search for environmental factors. Am.J Dis.Child 1986;140(12):1263-1267. PubMed
  73. Halpin, T. C., Byrne, W. J., and Ament, M. E. Colitis, persistent diarrhea, and soy protein intolerance. J Pediatr. 1977;91(3):404-407. PubMed
  74. Chorazy, P. A., Himelhoch, S., Hopwood, N. J., Greger, N. G., and Postellon, D. C. Persistent hypothyroidism in an infant receiving a soy formula: case report and review of the literature. Pediatrics 1995;96(1 Pt 1):148-150. DOI
  75. Gimenez, I., Martinez, R. M., Lou, M., Mayoral, J. A., Garay, R. P., and Alda, J. O. Salidiuretic action by genistein in the isolated, perfused rat kidney. Hypertension 1998;31(2):706-711. PubMed
  76. Van Wyk JJ, Arnold MB, Wynn J, and et al. The effects of a soybean product on thyroid function in humans. Pediatrics 1959;24:752-760. DOI
  77. Fruzza AG, Demeterco-Berggren C, Jones KL. Unawareness of the effects of soy intake on the management of congenital hypothyroidism. Pediatrics. 2012;130(3):e699-702. PubMed
  78. EFSA Panel on Food Additives and Nutrient Sources added to Food (ANS). Risk assessment for peri- and post-menopausal women taking food supplements containing isolated isoflavones. EFSA J. 2015;13(10):4246. DOI
  79. Vitolins MZ, Griffin L, Tomlinson WV, et al. Randomized trial to assess the impact of venlafaxine and soy protein on hot flashes and quality of life in men with prostate cancer. J Clin Oncol. 2013;31(32):4092-8. PubMed
  80. Persiani S, Sala F, Manzotti C, et al. Evaluation of levothyroxine bioavailability after oral administration of a fixed combination of soy isoflavones in post-menopausal female volunteers. Drug Res (Stuttg). 2016;66(3):136-40. PubMed
  81. Wu AH, Spicer D, Garcia A, et al. Double-blind randomized 12-month soy intervention had no effects on breast MRI fibroglandular tissue density or mammographic density. Cancer Prev Res (Phila). 2015;8(10):942-51. PubMed
  82. Yagami A, Suzuki K, Nakamura M, et al. Case of anaphylactic reaction to soy following percutaneous sensitization by soy-based ingredients in cosmetic products. J Dermatol. 2015;42(9):917-8. PubMed
  83. Zhang XM, Zhang YB, Chi MH. Soy protein supplementation reduces clinical indices in type 2 diabetes and metabolic syndrome. Yonsei Med J. 2016;57(3):681-9. PubMed
  84. Barni S, Mori F, Pantano S, Novembre E. Adverse reaction to benzathine benzylpenicillin due to soy allergy: a case report. J Med Case Rep. 2015;9:134. PubMed
  85. Gao M, Wang H. Frequent milk and soybean consumption are high risks for uterine leiomyoma: A prospective cohort study. Medicine (Baltimore). 2018;97(41):e12009. PubMed
  86. Upson K, Sathyanarayana S, Scholes D, Holt VL. Early-life factors and endometriosis risk. Fertil Steril. 2015;104(4):964-971.e5. PubMed
  87. Mumford SL, Weck J, Kannan K, Buck Louis GM. Urinary phytoestrogen concentrations are not associated with incident endometriosis in premenopausal women. J Nutr. 2017;147(2):227-234. PubMed
  88. Yamagiwa Y, Sawada N, Shimazu T, et al. Soy Food Intake and Pancreatic Cancer Risk: The Japan Public Health Center-based Prospective Study. Cancer Epidemiol Biomarkers Prev. 2020;29(6):1214-1221. PubMed

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Parsley 21 references
  1. Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
  2. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  3. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  4. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  5. Robbers JE, Tyler VE. Tyler's Herbs of Choice: The Therapeutic Use of Phytomedicinals. New York, NY: The Haworth Herbal Press, 1999.
  6. Foster S, Tyler VE. Tyler's Honest Herbal, 4th ed., Binghamton, NY: Haworth Herbal Press, 1999. DOI
  7. Eberhard P, Gall HM, Muller I, Moller R. Dramatic augmentation of a food allergy by acetylsalicylic acid. J Allergy Clin Immunol 2000;105:844 PubMed
  8. Tunali T, Yarat A, Yanardag R, et al. Effect of parsley (Petroselinum crispum) on the skin of STZ induced diabetic rats. Phytother Res 1999;13:138-41.. DOI
  9. Chuang CH, Doyle P, Wang JD, et al. Herbal medicines used during the first trimester and major congenital malformations: an analysis of data from a pregnancy cohort study. Drug Saf 2006;29:537-48. PubMed
  10. Ciganda C, and Laborde A. Herbal infusions used for induced abortion. J Toxicol.Clin Toxicol. 2003;41:235-239. PubMed
  11. Jakovljevic, V., Raskovic, A., Popovic, M., and Sabo, J. The effect of celery and parsley juices on pharmacodynamic activity of drugs involving cytochrome P450 in their metabolism. Eur.J Drug Metab Pharmacokinet. 2002;27(3):153-156. PubMed
  12. Kreydiyyeh, S. I. and Usta, J. Diuretic effect and mechanism of action of parsley. J Ethnopharmacol 2002;79(3):353-357. PubMed
  13. Yanardag, R., Bolkent, S., Tabakoglu-Oguz, A., and Ozsoy-Sacan, O. Effects of Petroselinum crispum extract on pancreatic B cells and blood glucose of streptozotocin-induced diabetic rats. Biol Pharm Bull. 2003;26(8):1206-1210. PubMed
  14. Bolkent, S., Yanardag, R., Ozsoy-Sacan, O., and Karabulut-Bulan, O. Effects of parsley (Petroselinum crispum) on the liver of diabetic rats: a morphological and biochemical study. Phytother.Res 2004;18(12):996-999.
  15. Ozsoy-Sacan, O., Yanardag, R., Orak, H., Ozgey, Y., Yarat, A., and Tunali, T. Effects of parsley (Petroselinum crispum) extract versus glibornuride on the liver of streptozotocin-induced diabetic rats. J Ethnopharmacol 3-8-2006;104(1-2):175-181. PubMed
  16. Peterson, S., Lampe, J. W., Bammler, T. K., Gross-Steinmeyer, K., and Eaton, D. L. Apiaceous vegetable constituents inhibit human cytochrome P-450 1A2 (hCYP1A2) activity and hCYP1A2-mediated mutagenicity of aflatoxin B1. Food Chem.Toxicol. 2006;44(9):147 PubMed
  17. Gadi, D., Bnouham, M., Aziz, M., Ziyyat, A., Legssyer, A., Legrand, C., Lafeve, F. F., and Mekhfi, H. Parsley extract inhibits in vitro and ex vivo platelet aggregation and prolongs bleeding time in rats. J Ethnopharmacol 8-17-2009;125(1):170-174. PubMed
  18. Arslan S, Ucar R, Caliskaner AZ. A Cases of Near-fatal Anaphylaxis: Parsley "Over-use" as an Herbal Remedy. Med Arch. 2014;68(6):426-7.
  19. Foti C, Cassano N, Mistrello G, Amato S, Romita P, Vena GA. Contact urticaria to raw arugula and parsley. Ann Allergy Asthma Immunol. 2011 May;106(5):447-8. PubMed
  20. Farzaei MH, Abbasabadi Z, Ardekani MR, Rahimi R, Farzaei F. Parsley: a review of ethnopharmacology, phytochemistry and biological activities. J Tradit Chin Med. 2013;33(6):815-26. PubMed
  21. Kurtaran M, Koc NS, Aksun MS, Yildirim T, Yilmaz SR, Erdem Y. Petroselinum crispum, a commonly consumed food, affects sirolimus level in a renal transplant recipient: a case report. Ther Adv Drug Saf 2021;12:20420986211009358.

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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

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