Vitamin U is the common name for S-methylmethionine (SMM), a naturally occurring compound found in cabbage, kale, and other vegetables. Researchers first identified it in the 1950s while studying why cabbage juice appeared to support stomach health. The “U” originally stood for “ulcer” in the early research. The name stuck, even though S-methylmethionine isn’t technically classified as a vitamin.

Not in the strict scientific sense. Classical vitamins are essential nutrients the body can’t produce on its own. S-methylmethionine doesn’t fit that definition cleanly. The name comes from 1950s research and has been used in the scientific literature ever since. Think of it as a vitamin-like compound: naturally occurring, food-derived, and studied for specific effects on the stomach lining.

It’s found naturally in cabbage, kale, Brussels sprouts, and other cruciferous vegetables, and in smaller amounts in celery, beets, and parsley. Each VitaminYOU capsule contains 500 mg, a concentration that would take several heads of cabbage to match through juicing alone. Why a supplement beats cabbage juice.

Research suggests S-methylmethionine supports the stomach lining in two ways: it may help the stomach produce more of its natural protective mucus, and it appears to help protect mucosal cells from damage. For a full breakdown of the studies, see the Global Vitamin U Research Database.

S-methylmethionine can’t be patented. It’s a naturally occurring compound, which means there’s no financial incentive for pharmaceutical companies to develop it into a drug. It’s been in the research literature for seventy years and used as a medication in two countries. It just never made it to US shelves. That’s the gap VitaminYOU was built to close.

With food is generally recommended, both for tolerability and because the stomach is actively working during a meal. There’s no strong evidence that time of day matters. Consistency is more important than timing.

Yes. Two capsules daily (1,000 mg) is within the range that appears in research and in common use. If you’re starting out, one capsule is a sensible place to begin before increasing.

S-methylmethionine is generally considered well-tolerated alongside other common supplements. No significant interactions have been documented in the published research. If you’re taking multiple things, it’s worth running it by your healthcare provider.

No significant side effects have been reported in the published research. Some people notice a faint sulfurous smell from the compound. This is normal and not a concern. Because S-methylmethionine is derived from cabbage, people with a known sensitivity to cruciferous vegetables should keep that in mind.

Yes. The capsule shell is made from Hypromellose, a plant-derived material. All other ingredients are vegan.

Yes. VitaminYOU is third-party tested for purity and potency.

VitaminYOU is manufactured in the United States.

VitaminYOU is a dietary supplement, not a drug. Under US law, dietary supplements are not individually approved by the FDA before going to market. We manufacture in compliance with FDA Good Manufacturing Practice (GMP) standards.

We ship to all 50 US states. We don’t currently ship internationally.

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