Supplements›Gut & digestion

Cabbage extract (vitamin U) for heartburn: how to take it

Cabbage extract may help if you drink a lot of coffee or alcohol, or often get heartburn or a heavy feeling in your upper stomach. The key is that a compound called vitamin U helps care for the stomach lining (the protective layer inside your stomach). From food, eat 100–200 g a day; for tablets or extracts, take the label amount with water.

Who it’s for

People with frequent heartburn or upper-stomach discomfort, and people who drink a lot of coffee or alcohol

Daily dose

100–200 g of raw cabbage a day (about 1/8 of a head); tablets or extract per the label

When

Every day, consistently — or every 2–3 days as an add-on

Best form

Tablets if the smell bothers you; raw or in salads if you're getting it from food

What is cabbage extract? What is vitamin U?

Cabbage contains a compound called vitamin U. Its proper name is S-methylmethionine (MMSC). Despite the name, it isn't a true vitamin — it's a compound derived from an amino acid.

Vitamin U is known for helping a damaged stomach lining recover. That's why it's also used as an ingredient in some stomach medicines.

Cabbage extract and cabbage tablets are concentrated forms of cabbage that make it easy to take.

Cabbage extract benefits

  • Protecting the stomach lining: Vitamin U helps the protective layer inside your stomach recover. Many people say they get less heartburn and their stomach feels more settled.
  • Constipation: It's high in fiber, which may help keep your bowels moving.
  • Antioxidant support: Sulforaphane (an antioxidant in cabbage-family vegetables) may help calm inflammation.
It works differently from stomach medication. Unlike drugs that reduce stomach acid, vitamin U leaves the acid alone and cares for the lining. So the two are seen as complementing each other. If you've been prescribed stomach medication, don't stop it on your own.

How to take it and how much

FormAmountTips
Raw cabbage100–200 g a day (about 1/8 of a head)Raw, in salads, or blended
Cabbage tablets or extractLabel amountWith a glass of water
  1. Taking it every day, consistently, is the basic approach. If you use it only as an add-on for heartburn, every 2–3 days is fine too.
  2. If you don't like the smell, tablets are easier.
  3. Vitamin U is sensitive to heat, so if you're after the benefits, eating it raw is better.

Side effects and cautions

  • Gas and stomach pain: Cabbage is high in sulfur compounds and fiber, so eating a lot can cause rumbling and pain.
  • Irritable bowel syndrome (IBS): Cabbage is a FODMAP food (carbs that tend to produce gas in the gut). More than 100 g a day may cause discomfort, so eat less.
  • Underactive thyroid (hypothyroidism): Cabbage contains compounds that can interfere with thyroid function (goitrogens). Avoid eating large amounts. Blanching it for 10–20 minutes removes almost all of these compounds.
If heartburn lasts more than a few weeks, or you have black stools or weight loss, don't rely on supplements — get checked by a doctor.

Medications and conditions to watch

  • Note Treatment for underactive thyroid — Eating a lot of raw cabbage may strain thyroid function — don't eat large amounts, and blanch it if you do

Frequently asked questions

Do cabbage tablets work?

The vitamin U in cabbage is known to help the stomach lining recover, so many people with frequent heartburn take it as an add-on. But it doesn't replace stomach medication.

Is vitamin U a vitamin?

No. It's called a vitamin, but it's a compound derived from an amino acid (S-methylmethionine). It's also used as an ingredient in some stomach medicines.

How much cabbage should I eat a day?

100–200 g of raw cabbage a day, or roughly 1/8 of a head. If you have IBS, keep it under 100 g.

Does cooked cabbage still work?

Vitamin U is sensitive to heat, so raw is better. But if you have an underactive thyroid, it's best to blanch it for 10–20 minutes.

Cabbage gives me a lot of gas

That's from its sulfur compounds and fiber. Try eating less or switching to tablets.

Related concerns

Indigestion & heartburnGut healthConstipation

Last updated 2026-10-12