The probiotic Korea has trusted for 30 years

Duolac Gold is the one Duolac is proudest of: a premium formula made for adults and older adults who want to look after their gut for the long run. It's also named a World-Class Product by Korea's Ministry of Trade, Industry and Energy (2024).

Duolac Gold: Available in 2 styles

Duolac Gold One-A-Day Packets (Take 1 Packet/Day): An easy once-daily stick pack with added vitamins A, B1, B2, B6, C, and E.

Duolac Gold Capsules (Take 1 Capsule/Day): An easy once-daily capsule for those who prefer probiotics without the added vitamins.

Both options feature six Korean-sourced probiotic strains, 66 billion CFU added and 10 billion CFU guaranteed, plus prebiotics. The probiotic strains have completed a human study involving Korean participants.

Three decades at the top

Trends come and go. Duolac Gold has stayed Duolac's premium best-seller for 30 years, because once people find a probiotic that works for them, they stick with it.

Nearly 100 million sold, and counting

The numbers speak for themselves.

• 1,712,247 boxes sold (2008–2023)
• 100,551,621 sticks and capsules sold (2008–2023)
• 31,773 customer reviews (2016–2024)

Figures from Duolac, covering Duolac Gold products and reviews on Duolac's own Korean stores.

“I've taken it for over 10 years.”

You don't stay with a supplement for a decade unless it earns its place. Here's what long-time customers in Korea say:

• “Duolac Gold has been my friend for 20 years.”
• “I've taken it every day for 10+ years. A product I trust.”
• “I've bought it for my mother for over 10 years. There's no probiotic like it.”
• “Almost 10 years now. I'll probably take it for life.”
• “We've taken it since 2015. Duolac looks after our family's gut health.”

Reviews from Duolac's Korean online store, translated by Gochujar.

Tried them all? This is where people land.

If any of these sound like you, you've found your probiotic.

• You want a premium, high-count probiotic
• You want strains that are 100% Korean in origin
• You want probiotics recognized around the world
• You're done switching and want one you can stick with

Simple to take, every day

1 stick a day is all it takes. Tear, pour, done.

• Made for adults and older adults
• Easy powder sticks: 1 stick, once a day
• 30 sticks (3 g each), a full 30-day supply
• 10 billion CFU guaranteed in every serving

Six reasons it stands apart

• 6 probiotic strains, 100% Korean in origin, chosen with Korean guts in mind
• Formulated only with strains on the US FDA GRAS register*
• Strains tested in human trials with Korean adults
• A science-backed strain formula built for adult gut health
• Patented dual coating (Korea, US, EU, Japan, China) that helps cultures reach the gut alive
• A premium best-seller for 30 years

*GRAS relates to ingredient safety, not to health benefits.

What's inside every stick

66 billion CFU go into every serving, so a full 10 billion CFU is guaranteed by the time it reaches you. Probiotics may help good bacteria thrive, keep harmful bacteria in check, and support regular, comfortable digestion.

Plus prebiotics (fructooligosaccharides and galactooligosaccharides) to feed the good bacteria, and vitamins A, B1, B2, B6, C and E.

How to take: 1 stick once a day. Store at room temperature.

Made for you if…

• You want probiotic strains that are 100% Korean in origin
• You want strains backed by human trials with Korean adults
• You need a high-count probiotic you can rely on
• Your parents' digestion isn't as regular as it used to be
• You're busy, eat on the go, and your gut feels it
• You have a sensitive stomach

Specialists, not generalists

Before you choose a probiotic, ask who made it. Duolac has spent 30 years researching one thing: Korean-origin probiotic strains.

6 CBT strains, 100% from Korea

Isolated from Koreans and put through human trials with Korean adults, so you know exactly what you're taking.

• Bifidobacterium longum CBT-BG7
• Bifidobacterium bifidum CBT-BF3
• Bifidobacterium lactis CBT-BL3
• Lacticaseibacillus rhamnosus CBT-LR5
• Lactobacillus acidophilus CBT-LA1
• Streptococcus thermophilus CBT-ST3

Developed in-house, over 30 years

Duolac doesn't buy in its strains. It develops them itself.

• 100% Korean strains, sourced from healthy Koreans and traditional Korean fermented foods
• Safety verified in human trials with Korean adults
• Strain-by-strain research using next-generation (NGS) genome sequencing

47 scientists behind every stick

Cell Biotech's Microbiome Institute, the team behind Duolac, brings together 47 researchers with master's and doctoral degrees. Their track record:

• 107 patents
• 35 human trials
• 124 published papers
• 231 research achievements in total (as of 2025)

What does “CBT” mean?

Every probiotic strain has a name, just like people do. CBT stands for Cell Biotech, the company behind Duolac, and it marks strains Duolac developed itself. When you see CBT, you know where it came from.

Example: genus Lactobacillus, species acidophilus, strain CBT-LA1.

Safety you can check for yourself

Probiotics are live bacteria, so safety matters more than anything. As of February 2024, Duolac has more probiotic strains on the US FDA GRAS (Generally Recognized As Safe) register than any other company in the world, and Duolac Gold uses only GRAS-listed strains.

GRAS is the FDA's safety recognition for food ingredients. It relates to safety, not to health benefits.

Verified at every level

Duolac doesn't just say its probiotics are safe. It shows you the paperwork.

• Strain functionality recognized under Korea's MFDS health functional food standards
• Strains deposited with Germany's DSMZ and the Korean Collection for Type Cultures (KCTC)
• DNA sequence of each strain registered with the US NCBI
• Exported to 55 countries; No.1 Korean probiotic exporter 11 years running (2013–2023)
• World-Class Product brand, Korea's Ministry of Trade, Industry and Energy (2024)

Quality certifications: GMP, CODEX HACCP, ISO 9001, MUI Halal, OK Kosher, BPOM. Some apply to specific products or strains.

A formula built for grown-up guts

Not a random mix. Using years of strain-analysis data, Cell Biotech's Microbiome Institute balanced the blend at 47% Bifidobacterium and 53% Lactobacillus and other lactic acid bacteria.

• Bifidobacteria: B. longum CBT-BG7, B. bifidum CBT-BF3, B. lactis CBT-BL3 (all patented strains)
• Lactic acid bacteria: L. rhamnosus CBT-LR5, L. acidophilus CBT-LA1 (patented strains), S. thermophilus CBT-ST3

Why the ratio makes the difference

More strains isn't automatically better. Each one lives in a different part of the gut, grows at its own pace, and our gut flora shifts as we age. Duolac tunes the ratio for every product so each strain can reach where it's needed and do its job.

Proven in a human trial

In a clinical study of Duolac Gold's six strains in Korean adults with sensitive guts, 68% of those taking the probiotics reported overall relief of gut discomfort, nearly double the 37.5% in the group that didn't (p<0.05).

Yoon JS et al., “Effect of multispecies probiotics on irritable bowel syndrome: a randomized, double-blind, placebo-controlled trial,” Journal of Gastroenterology and Hepatology 29 (2014): 52–59. Individual results may vary.

Built for kimchi, garlic and chili

Love bold Korean food? So do these strains. In a lab (cell) study, all six Duolac Gold strains kept growing alongside garlic, onion, ginger, red chili and Cheongyang chili. Results in the body may differ.

Kim et al., Korean Journal of Food and Nutrition 50(1) (2021): 16–28.

Protected all the way down

A probiotic only helps if it survives the trip. Duolac's patented dual coating wraps each culture in a tough matrix of protein and polysaccharide, shielding it from stomach acid and bile so it reaches your gut alive.

Patented in 5 major markets

This technology is protected by patents in the European Union, United States, South Korea, China and Japan.

Up to 221× more reach the gut

The coating makes a real difference. In a human study, people taking dual-coated probiotics had up to 221 times more of the strain in their gut (L. rhamnosus CBT-LR5) than those taking uncoated probiotics.

Randomized, double-blind, controlled study of 40 adults over 2 weeks (20 uncoated, 20 dual-coated; 5 × 10⁹ viable cells a day). Source: “Effect of double-coated probiotic formulation on functional constipation in the elderly.” Individual results may vary.

No fridge? No problem.

Duolac's CBT strains were confirmed to survive from −70°C all the way to 40°C. Keep it in your bag, your desk or your suitcase. Perfect for shipping overseas, too.

Tested by the Korea Functional Food Research Institute (samples provided by Cell Biotech).

Alive, and it shows

Under the microscope, Duolac's CBT probiotics kept multiplying over time in strain-by-strain lab tests. Live cultures, confirmed.

Tested by the Korea Food Research Institute (samples provided by Cell Biotech).

Trusted far beyond Korea

Duolac isn't just Korea's favourite. It's a probiotic the world has noticed.

• Exported to 55 countries; No.1 Korean probiotic exporter 11 years running (2013–2023)
• No.2 in pharmacy health-supplement sales in Denmark, the home of probiotics (DLI data, Dec 2023)
• More strains on the US FDA GRAS register than any other company
• World-Class Product, Korea's Ministry of Trade, Industry and Energy (2024)

Figures relate to the Duolac brand.

From strain to your door, all Duolac

No outsourcing, no shortcuts. Duolac handles every step in-house to global standards, so the quality you get is the quality they intended.

• Strain development and research
• Culturing and isolation
• Patented coating and freeze-drying
• Strain blending
• Finished product manufacturing
• Quality testing
• Delivery and customer service

Q&A

Why Shop with Gochujar?

Flat $5 International Shipping

Just $5 to ship your order from Korea, or free when you order 2 or more items. No surprises at checkout.

Based Locally in Korea

We live here and buy directly from local producers in small batches, so what reaches you is always fresh and current.

Built on Trust, Not Ads

We’ve never spent a cent on marketing. Gochujar has grown purely through word of mouth and the trust of customers around the world.

We ship orders daily from Korea