Herbs lost their antioxidant scores in 2012, but parsley’s vitamin K still counts

Key takeaways

• In 2012, the U.S. Department of Agriculture pulled its antioxidant (ORAC) database, saying the test-tube numbers didn’t show effects in the body and were being misused to sell products¹².
• By USDA figures, two tablespoons of chopped fresh parsley carry about 120 micrograms of vitamin K, more than the 90-microgram daily Adequate Intake for women⁷⁸.
• If you take warfarin, federal health advice is to keep your vitamin K intake steady from day to day, not to give up parsley or leafy greens⁸⁹¹⁰.
• From 2000 to 2017, the CDC tied six U.S. outbreaks of the Cyclospora parasite to basil or cilantro, two of them only as likely or suspected sources, including one that sickened 582 people in Florida⁴.
• Rinse fresh herbs under cool running water just before you use them¹¹¹², and keep basil cool but out of the fridge¹¹¹³.

On June 26, 1997, guests at a corporate luncheon in Fairfax, Virginia, ate a catered pasta salad dressed with basil pesto. Of the 44 people who ate it, 43 got sick⁵.

The cause was Cyclospora, a one-celled parasite. Health officials linked 25 confirmed clusters of illness around northern Virginia, Washington, D.C., and Baltimore to fresh basil from a single food company. That company said it routinely washed the basil it used for pesto⁵.

Most of us think of herbs as the gentlest thing in the kitchen. In many ways they are. Parsley, basil, cilantro, thyme and sage turn beans, grains and vegetables into food people want to eat, often with less salt.

But three facts rarely make it onto herb-lover lists. The government withdrew the antioxidant scores that made herbs sound like medicine. One common herb is a serious source of vitamin K, which matters for anyone on the blood thinner warfarin. And because we eat many herbs raw, they are a food-safety item, not just a garnish.

This guide covers all three, plus a fresh herb guide and a salt-free blend you can mix tonight.

USDA pulled the antioxidant scores that made herbs sound like medicine

For years, food and supplement sellers quoted ORAC numbers. ORAC stands for oxygen radical absorbance capacity, a test-tube measure of a food’s antioxidant activity. USDA’s Nutrient Data Laboratory published a database of these values for selected foods.

In June 2012, the lab took the database down¹². Its reasons, as reported by two trade publications, were blunt. USDA said a growing body of evidence showed the scores didn’t reflect how particular plant compounds, polyphenols among them, act on human health¹².

USDA added that test-tube results can’t be carried over to what happens in a living body. It also noted that trials of dietary antioxidants had produced mixed results². Last, it said the scores had become a marketing tool for food and supplement sellers and a shopping guide for consumers, uses the data couldn’t support¹².

Not everyone agreed. Ronald Prior, a former USDA researcher, conceded the numbers had sometimes been misused but argued they could still be useful in the right hands².

What does that mean for your spice rack? An herb’s antioxidant score, wherever you see it, tells you nothing reliable about what the herb does inside you. USDA didn’t say plant foods are useless. It said the benefits of plant-rich foods may work through other routes that aren’t fully understood².

That’s a more honest frame for herbs. They are valuable because they make healthy food taste good, not because they top a lab leaderboard.

Herbs add flavor more than nutrition, and parsley is the exception

In the amounts people sprinkle on dinner, many herbs supply very little. Purdue Extension lists two tablespoons of chopped fresh basil at about 1 calorie, with 5% of the Daily Value for vitamin A¹³.

Vitamin K is where the numbers get interesting. USDA’s nutrient database gives these values⁷:

• Fresh parsley: 984 micrograms in 1 cup, chopped, or about 246 in a quarter cup.
• Fresh basil: 10.4 micrograms in 5 leaves.
• Fresh cilantro: 12.4 micrograms in a quarter cup.
• Dried thyme: 17.1 micrograms in 1 teaspoon.
• Dried basil or ground sage: 12 micrograms in 1 teaspoon.

For context, the National Institutes of Health’s Office of Dietary Supplements (ODS) sets the daily Adequate Intake for vitamin K at 120 micrograms for men and 90 for women⁸. Vitamin K helps your blood clot.

Do the math on parsley and it stands apart. One tablespoon of chopped parsley has about 60 micrograms by USDA figures, and two tablespoons pass the women’s daily amount⁷⁸.

Picture a tabbouleh with a quarter cup of chopped parsley in each serving. That bowl delivers about 246 micrograms, close to triple the women’s Adequate Intake⁷⁸. An NIH Clinical Center handout for patients lists the same 246-microgram figure⁹.

For most people, that’s good news. ODS reports no harm from vitamin K in food or supplements, and no upper limit has been set⁸.

On warfarin, keep your parsley steady, not off the menu

Warfarin (Coumadin) works against vitamin K’s role in clotting. ODS explains that a sudden change in how much vitamin K you eat can weaken or strengthen the drug’s effect, a potentially serious interaction⁸.

The NIH Clinical Center’s patient advice is to eat about the same amount of vitamin K each day⁹. A sudden increase can make warfarin work less well. A big drop can make it work too strongly⁹.

The handout doesn’t tell people to quit greens. It says not to make major changes. If you eat a spinach salad every day, keep eating it⁹.

MedlinePlus, the National Library of Medicine’s consumer site, names parsley along with spinach, lettuce, watercress and other greens¹⁰. You don’t have to avoid them, it says, though it suggests keeping portions small. At a minimum, keep the amount steady from day to day and week to week, and check with your provider before a big change in diet¹⁰.

Herb lovers face a seasonal twist. A garden can turn out a flood of parsley in early summer, and a pesto habit can come and go with the basil. If your herb eating swings with the seasons, tell whoever manages your warfarin, so blood tests can catch any change.

Concentrated herb products are a separate question. The NIH handout lists garlic, ginger and turmeric among herbal products that can alter warfarin blood tests, and it advises avoiding dietary supplements unless a doctor approves⁹. If you take any of them in capsule form, check first.

If you take a different blood thinner, ask your pharmacist whether any of this applies to you.

Basil and cilantro have caused large parasite outbreaks

Herbs cause outbreaks for a simple reason: we often eat them raw. CDC records show 39 U.S. foodborne outbreaks of cyclosporiasis from 2000 through 2017, with 1,730 cases⁴.

Investigators identified or suspected a specific food in just 17 of those outbreaks⁴. Six of the 17 involved basil or cilantro⁴:

• Basil: 57 cases in Illinois in 2004, with basil the likely source; 582 cases in Florida in 2005, traced to basil from Peru; and 30 cases in Connecticut in 2005, with basil suspected.
• Cilantro from Mexico: 38 cases in Texas in 2013; 26 in Texas in 2014; and 90 across Georgia, Texas and Wisconsin in 2015.

The 2005 Florida outbreak was the largest in that CDC table⁴. Outbreaks peaked in May, June and July⁴.

CDC notes a tracing problem, too. When produce is used as a garnish or mixed with other foods, it’s hard to pin illness on one item⁴. Herbs are often both.

Outbreaks kept coming. In 2019, fresh basil exported by Siga Logistics of Morelos, Mexico, was linked to 241 laboratory-confirmed cases in 11 states, and six people were hospitalized⁶. The company recalled the basil on July 24, 2019⁶.

Most samples test clean, though. In FDA sampling reported by the trade publication FreshPlaza, the agency checked 958 samples of cilantro, parsley and basil through mid-2019¹⁴. It found Cyclospora in 10 of the 426 samples tested for it, and Salmonella in 12 samples overall¹⁴. The report noted that testing was still underway and that no conclusions could be drawn yet¹⁴.

The cilantro case: an import alert that returns every April

After outbreaks tied to cilantro from Puebla, Mexico, in 2012, 2013, 2014 and 2015, the FDA concluded the problem wasn’t a one-time accident³. It found the parasite in cilantro from several Puebla firms³.

What inspectors saw from 2013 to 2015 explains why. FDA and Mexican officials reported human feces and toilet paper in the fields and near packing houses³. Some farms had poorly kept toilets and handwashing stations, or none at all. At one firm, a tank of handwashing water tested positive for the parasite³.

The FDA’s answer is Import Alert 24-23. Each year from April 1 through August 31, cilantro from Puebla can be detained at the border without the FDA first examining it, unless the firm has shown the problems are fixed and is on the agency’s “Green List”³. The FDA republished the alert in February 2026³.

One line in the alert matters in home kitchens. The FDA says it knows of no evidence that lime or antimicrobial treatments work against Cyclospora³. A squeeze of lime makes salsa taste great. It doesn’t sanitize the cilantro.

Rinsing helps, storage matters, and basil breaks the rules

Washing still makes sense for dirt and many germs. Health Canada’s advice is to rinse herbs under cool running water and skip soap or other cleansers¹¹. It says plain water works as well as produce washes, and it warns that dunking herbs in a filled sink can spread germs to them¹¹.

University of Florida extension experts add a timing rule: rinse herbs just before you use them, then shake or pat them dry¹². Remember the 1997 outbreak, though. The company said it washed its basil⁵. Rinsing helps; it can’t promise a clean herb.

Storage advice mostly agrees. Health Canada says to keep unwashed herbs in the crisper drawer in a sealed bag for up to five days¹¹. Florida’s extension experts say most herbs keep about five days that way, and to throw out fresh herbs left at room temperature more than two hours¹².

Basil is where the experts split. Cold can blacken its leaves, so Health Canada says to keep it unwashed and out of the fridge¹¹. Purdue Extension suggests a cool spot of 50 to 65 degrees, with stems in a glass of water changed daily¹³. Florida’s experts advise refrigerating fresh herbs promptly and suggest keeping basil and cilantro stems down in a glass of water with a loose bag over the top¹².

Our take: buy basil you’ll use within a few days, stand it in water in the coolest part of the kitchen, and rinse it right before it hits the plate. Freeze extras: Purdue suggests rinsing, patting dry and freezing in a bag¹³.

Keep herbs away from raw meat and its juices, and wash cutting boards, counters and utensils with warm, soapy water before and after¹¹¹³. For herbs stored in oil, see our article on respecting nature, which covers that botulism risk.

Your fresh herb guide

Use this table when you shop, store and cook. Pairings are kitchen suggestions, not health claims.

Herb	Pairs well with	Keep it fresh	Nutrient of note	Safety tip
Basil	Tomatoes, beans, eggs, peaches	Stems in water at cool room temperature; use within days1113	About 10 mcg vitamin K in 5 leaves7	Linked to outbreaks including 1997, 2005 and 2019; rinse just before use456
Parsley	Lemon, bulgur, potatoes, fish	Crisper drawer, sealed bag, up to 5 days11	About 60 mcg vitamin K per tablespoon7	On warfarin, eat about the same amount each week910
Cilantro	Black beans, lime, rice, avocado	Stems in water with a loose bag, or the crisper drawer1112	About 12 mcg vitamin K per quarter cup7	Lime won’t disinfect it; rinse under running water311
Thyme	Roast chicken, mushrooms, lentil soup	Dried: sealed jar away from stove heat	About 17 mcg vitamin K per teaspoon, dried7	Count it in a steady vitamin K routine if you use a lot
Sage	Squash, white beans, pork	Dried: sealed jar; fresh: crisper drawer11	About 12 mcg vitamin K per teaspoon, ground7	Cooking amounts only; this table isn’t about sage supplements

What the evidence shows

Claim	Evidence rating	What it rests on
A high antioxidant (ORAC) score means an herb protects your health	Evidence says no, or unsafe	USDA withdrew the scores, saying lab values don’t reflect effects in the body12
Fresh parsley is a rich source of vitamin K	Strong evidence	USDA nutrient measurements7
Keeping vitamin K steady helps keep warfarin stable	Strong evidence	NIH Office of Dietary Supplements and Clinical Center guidance89
Fresh basil and cilantro can carry Cyclospora	Strong evidence	Repeated CDC-investigated outbreaks and FDA inspections346
Rinsing alone makes fresh herbs parasite-free	Not enough evidence	A washed-basil outbreak; FDA knows of no evidence that lime or antimicrobial treatments work35
Cooking with herbs and spices helps people eat less salt	Promising but early	Covered in our article on spices and salt

Herbs belong to every food tradition

Nearly every cuisine has a green sauce or a fistful of herbs at its heart: Italian pesto, Argentine chimichurri, Levantine tabbouleh, Mexican salsa verde, South Asian mint and cilantro chutneys. These are some of the oldest natural-health habits there are, and they cost little.

Respecting that heritage doesn’t require inflating it. Herbs don’t need lab antioxidant rankings to earn a place at the table. Their proven gift is flavor that makes vegetables, beans and grains worth eating every day.

Growing your own is a natural next step, and our home gardening article covers soil, water and manure safety. Wherever your herbs come from, the same habits apply: rinse them, store them well, and treat parsley as the vitamin K source it is.

Questions readers ask

The bottom line

Fresh and dried herbs are among the best tools in a natural kitchen because they make healthy food taste good. Their lab antioxidant scores were retired by the agency that published them, so judge herbs by the meals they make possible.

Two facts deserve a place next to the cutting board. Parsley carries real vitamin K, so people on warfarin should keep it steady, not banish it. And basil and cilantro are eaten raw, so rinse them, store them well, and buy only what you’ll use soon.

Related reading

• Spices can help you cut salt, though some batches have carried lead
• A classic Mediterranean diet trial used canola oil, so the pattern travels well
• Home gardens save money until you count your hours, but a trial found other payoffs
• Nature makes both medicine and deadly poison, and respecting it means telling them apart
• Some healthy habits clash with your medicines, so check these goals first

Sources

1. Cosgrove J. “ORAC Database Withdrawn.” Nutraceuticals World, June 21, 2012. nutraceuticalsworld.com
2. SupplySide Supplement Journal (Natural Products Insider). “USDA Says ORAC Tests Useless, Removes Database for Selected Foods.” June 12, 2012. supplysidesj.com
3. U.S. Food and Drug Administration. “Import Alert 24-23: Detention Without Physical Examination of Fresh Cilantro From the State of Puebla, Mexico – Seasonal (April 1 – August 31).” Published February 4, 2026. accessdata.fda.gov
4. Centers for Disease Control and Prevention. “U.S. Foodborne Outbreaks of Cyclosporiasis—2000–2017.” Archived CDC web page, last reviewed January 20, 2021. stacks.cdc.gov
5. Centers for Disease Control and Prevention. “Outbreak of Cyclosporiasis: Northern Virginia–Washington, D.C.–Baltimore, Maryland, Metropolitan Area, 1997.” Morbidity and Mortality Weekly Report, 1997;46(30):689. cdc.gov
6. Centers for Disease Control and Prevention. “Outbreak of Cyclospora Infections Linked to Fresh Basil from Siga Logistics de RL de CV of Morelos, Mexico.” Final update, September 30, 2019.
7. U.S. Department of Agriculture, Agricultural Research Service. “USDA National Nutrient Database for Standard Reference, Release 28: Vitamin K (Phylloquinone) Content of Selected Foods.” Hosted by the NIH Office of Dietary Supplements, 2015. ods.od.nih.gov
8. NIH Office of Dietary Supplements. “Vitamin K: Fact Sheet for Health Professionals.” Updated March 29, 2021. ods.od.nih.gov
9. National Institutes of Health Clinical Center, Drug-Nutrient Interaction Task Force. “Important Information to Know When You Are Taking: Warfarin (Coumadin) and Vitamin K.” Dated September 5, 2012 (copy hosted by Austin Regional Clinic, 2015). austinregionalclinic.com:443
10. MedlinePlus, National Library of Medicine. “Taking Warfarin.” Reviewed January 1, 2025. medlineplus.gov
11. Health Canada. “Food Safety Tips for Fresh Herbs.” Modified June 7, 2013. canada.ca
12. University of Florida IFAS Extension, Bay County. “Safe Handling of Fresh Herbs.” June 15, 2018.
13. Purdue University Extension. “FoodLink: Basil.” Accessed October 2026. extension.purdue.edu
14. FreshPlaza. “Results of FDA Sampling of Fresh Herbs and Processed Avocado.” September 23, 2019. freshplaza.com