Supplement analysis backed by scientific evidence · PT

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Moderate evidenceHeart & metabolic

Tagatose

A rare sugar with about 90 percent of the sweetness of sucrose but a much smaller glycaemic effect. Meta-analyses of human trials confirm it blunts the post-meal glucose rise; evidence for weight loss or long-term metabolic benefit is much thinner.

Evidence last reviewed: August 2026

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What the science says

  • Post-meal glucose response Moderate evidence

    A systematic review and meta-analysis of controlled human intervention trials of allulose and tagatose found reductions in postprandial glucose compared with sucrose or glucose. Trials were mostly short-term and acute.

  • Replacing sugar in the diet Moderate evidence

    A meta-analysis of fructose and its epimers, which includes tagatose, found favourable effects on postprandial carbohydrate metabolism when they replace other sugars. The benefit is a substitution effect rather than an active metabolic treatment.

  • Longer-term metabolic outcomes Limited evidence

    A systematic review of rare sugars in human trials concluded that evidence for sustained effects on HbA1c, body weight or lipids remains sparse and of low certainty. Most positive findings come from single-meal studies.

Dosage & safety

Studied doseStudies used roughly 5–15 g per serving, typically as a sugar replacement in a meal or beverage; some trials used up to 15 g three times daily. Doses above about 30 g at once commonly cause digestive symptoms.
SafetyPoorly absorbed, so it ferments in the colon and causes gas, bloating and diarrhoea at higher doses, with tolerance improving gradually. It transiently raises serum uric acid, which matters for people with gout. Avoid with hereditary fructose intolerance. It is far more expensive than common sweeteners.

Scientific references

Where to buy

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