Broccoli compounds can inhibit some bacteria in laboratory tests, but eating broccoli has not been shown to treat an infection. The findings depend on the compound or extract tested, how the broccoli was prepared, and which organism was exposed.
What does “bacterial growth is inhibited by broccoli” mean?
Most of the evidence concerns sulforaphane, a compound associated with broccoli and other cruciferous vegetables, or extracts made from broccoli. Broccoli contains glucoraphanin, which can be converted into sulforaphane through the action of the enzyme myrosinase. A test showing that sulforaphane or an extract slows a bacterium in a laboratory is not the same as showing that a serving of broccoli prevents or cures an infection.
As an Amazon Associate I earn from qualifying purchases.
A 2025 review summarized 28 reports on sulforaphane’s antibacterial effects, including studies of different bacteria, virulence factors, immune responses, and human research. It describes an active research area, not an established broccoli-based treatment for infections (2025 review, PubMed).
Which bacteria have been affected in studies?
Results are specific to the organisms, strains, compounds, and test conditions examined. In a 2008 in vitro study, sulforaphane inhibited 23 of 28 tested microbial species. For those inhibited, the reported minimum inhibitory concentrations were 1–4 μg/mL. The study reported resistance in Pseudomonas aeruginosa, three MRSA isolates, and Candida albicans. The panel included fungi as well as bacteria, so the result should not be read as a universal effect on bacteria (Johansson, Pavia, and Chiao, 2008).
#1 Best Overall
- Brassica Oleracea Var. Italica: These finest quality, non-GMO, USDA Organic Waltham 29 Broccoli seeds produce crisp, crunchy, dark greenish-blue florets, leaves and stems that are packed with flavor and vitamins. They’re great on a plate!
- For Best Results: Harvest broccoli in the morning, when the buds of the head are firm and tight, just before the heads flower. Store in a refrigerator up to 5 days; or blanch and freeze for up to a year.
- Freshly Packed: These seeds are packed for the current growing season and will provide high germination rates next year as well.
- Certified Organic: All Purely Organic Seeds are open pollinated, non-GMO (not genetically modified), heirloom, organic seeds. Each Purely Organic Seed Packet carries the USDA Organic Seal signifying that is has passed rigorous standards and been certified organic by a USDA Accredited agency.
- Premium Packaging: All seeds from Purely Organic Products are packaged in individually styled packets ideal for gifts, storage or immediate use. Each packet displays the plant variety on the front with instructions and plant facts on the back.
Other studies focused on Helicobacter pylori, a bacterium associated with stomach disease. A 2002 study reported sulforaphane’s bacteriostatic activity against reference strains and clinical isolates, including antibiotic-resistant isolates. “Bacteriostatic” means inhibiting growth; it does not by itself show that a food eliminates the bacterium or treats illness (2002 study in PubMed Central).
A 2010 study examined sulforaphane and related compounds found in broccoli sprouts and reported anti-H. pylori activity in laboratory tests. It provides evidence about tested extracts and compounds, not proof that eating sprouts treats an infection (2010 study, PubMed).
Rank #2
- GROW NUTRITIOUS BROCCOLI SPROUTS AT HOME: Enjoy vitamin-packed organic broccoli sprouts with Nature Jims' broccoli sprout seeds. Ideal for indoor and outdoor growing, these seeds for sprouting offer fresh, healthy sprouts in no time.
- CERTIFIED ORGANIC BROCCOLI SEEDS FOR SPROUTING: Our non-GMO, organic broccoli seeds are renowned for quality, ensuring you receive premium seeds for sprouting. Perfect for growing nutrient-rich broccoli sprouts right at home.
- SWIFT-GROWING MICROGREEN SEEDS: Nature Jims' broccoli seeds for sprouting sprout in just 5 days! Enjoy fresh, crunchy sprouts in no time, ideal for those who want healthy microgreens that grow quickly.
- HEALTH BENEFITS OF BROCCOLI SPROUTS: Packed with sulforaphane, our organic broccoli sprout seeds elevate your defense system and promote healthy digestion for overall wellness. Enjoy the power of nature with every sprout!
- ESTABLISHED QUALITY SINCE 1955: With nearly 60 years of experience, Nature Jims has been providing premium organic sprouting seeds and microgreens. With unwavering confidence in our product, we ensure the quality of our seeds.
Does cooking broccoli change its measured antibacterial activity?
It can change the result in a laboratory assay, but the findings do not amount to general cooking advice. In a 2020 study, raw broccoli extract showed no antimicrobial activity except against Bacillus cereus; extracts from cooked broccoli showed activity against several tested pathogens. The researchers also examined cooked broccoli with mustard seeds, which can supply myrosinase. These were findings about particular extracts under laboratory conditions, not evidence that a particular cooking method prevents foodborne illness (Abukhabta and colleagues, 2020).
Free tools Windows power users keep installed
One-click scans. No signup required.
What did the human study actually measure?
The 2020 paper included a soup-feeding study involving 11 people with ileostomies. It examined whether broccoli phytochemicals reached the digestive tract, not whether participants’ infections improved. Less than 1% of sulforaphane was recovered in ileal fluids in the study. Adding mustard seed powder increased colon-available sulforaphane sixfold, but material from the ileal sample with the highest sulforaphane level did not inhibit E. coli K12 in the reported assay.
Rank #3
- Beautiful - Large premium packet of Waltham 29 Broccoli (Brassica oleracea) seeds. A reliable heirloom that produces 5-6" blue-green heads and an abundance of side shoots. Waltham 29 is adapted for both drought and cold tolerance. Minimum of 750 mg per packet (about 200 seeds).
- Productive - Waltham 29 Broccoli germinates in 7-14 days when soil temps are 70-75°F. Plant 1/4” deep and space 4-6” apart in an area with full sun. This variety will grow 20-24” tall with a spread of 12-16”. Heads will mature in 50-60 days, plant in USDA zones 3-10.
- Good Eats - Enjoy this delicious and nutritious broccoli raw, roasted, or added to soups, stir-fries, pastas, salads and more.
- Easy to Grow - Instructions included on each packet. Plus, we are available to answer all your questions. If these seeds don’t germinate, we will happily make it right for you.
- Safe and Sustainable - Our operation is fully solar powered, and Sow Right Seeds has taken the Safe Seed Pledge to sell only fresh Non-GMO heirloom seeds for you and your family.
The authors concluded that sulforaphane-rich broccoli extracts had antimicrobial effects in vitro and that sulforaphane-enriched broccoli soup may inhibit bacterial growth in the stomach and upper small intestine, but not in the terminal ileum or colon. This limited conclusion is not evidence that soup treats a bacterial infection in a person.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.What can you conclude if you are considering broccoli for an infection?
- Broccoli-derived sulforaphane and some broccoli extracts have inhibited particular microbes in laboratory studies.
- Effects vary by organism, strain, extract, and preparation; some tested organisms or isolates were resistant.
- The small human component examined delivery of compounds, not clinical treatment outcomes.
- These studies do not establish broccoli as an antibiotic substitute, a way to prevent foodborne illness, or a treatment for an active infection.
Broccoli can be part of a normal diet, but suspected bacterial infections require appropriate medical assessment rather than relying on broccoli or broccoli sprouts.
Quick Recap
Rank #4
- Grow Garden Broccoli - Plant Waltham 29 for tight blue-green heads and smaller side shoots after the main harvest. This cool-season heirloom brings classic broccoli to vegetable beds and raised gardens.
- 250-Seed Yield Range - At a 20-70% productive-plant range and 1 lb average per plant, 250 seeds could yield about 50-175 LBS in good conditions; actual harvest varies with germination, weather, spacing, timing, and care.
- Start with Seeds - Sow 1/4-1/2 inch deep in individual starter pots or seed-starting cells. Aim for 70-80 F in the seed zone; emergence commonly takes 5-10 days under suitable conditions. Keep the mix moist with good drainage.
- Give Heads Room - Harden seedlings and transplant 18-24 inches apart in full sun. Time growth for cool weather, water evenly, and cut the central head while buds remain tight; smaller side shoots can follow.
- One Packet, Future Plantings - 250 Waltham 29 broccoli seeds in a waterproof RDR Seeds packet with growing guidance, dated for the current or next planting season. Store cool, dry and tightly sealed. Broccoli seed generally remains viable for about 3-5 years under good storage conditions; germination declines with age.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
