Also known as: Potato protein extract, Proteinase inhibitor II, PI2, Solanum tuberosum extract
Branded IngredientsEmerging evidence
A potato protein extract sold for appetite control, working through a satiety hormone rather than as a stimulant. Mechanistically interesting, with a small and largely single-source evidence base.
Typical dose
300.0–300.0 mg per day
30-60 minutes before the largest meal
What it is
Slendesta is an extract of potato protein standardised to proteinase inhibitor II, a protein potatoes produce naturally as a defence against insects.
It contains no stimulants, which distinguishes it from most appetite products. The mechanism is hormonal rather than a matter of blunting appetite through nervous system arousal.
Doses are small, around 300 mg, of which a specified proportion is the active protein. It appears in weight management formulas rather than being widely sold alone.
How it works
Proteinase inhibitor II slows the breakdown of cholecystokinin, a hormone released by the small intestine when food arrives. CCK signals fullness to the brain and slows gastric emptying.
By slowing its degradation, the satiety signal is proposed to persist longer, reducing how much is eaten at the following meal.
This is a genuinely different approach from stimulant-based appetite suppression, and CCK is a well-established satiety signal rather than a speculative target. The question is whether the effect is large enough at supplemental doses to matter.
What the evidence shows
A small number of trials have reported reduced hunger, increased fullness and modest reductions in body weight over several weeks compared with placebo.
The research is limited in volume and largely linked to the ingredient's producer, with independent replication scarce.
Reported weight effects are small, in line with essentially everything in the appetite category. The mechanism is more interesting than the results, which is a fair summary of a great many supplements in this space.
Dosing
The dose used in the research is 300 mg, taken 30 to 60 minutes before a meal, usually the largest meal of the day.
Timing matters, since the mechanism depends on the satiety signal being active as food arrives. Taken with or after the meal it has much less to work on.
It is stimulant-free, which makes it usable later in the day when caffeine-based appetite products are not. That is its clearest practical advantage. Expectations should be modest: it may take the edge off hunger rather than change what you eat.
At a glance
Common forms
Slendesta (within weight management formulas), Potato protein extract capsules
Half-life / duration
Acute effect on satiety around the following meal
Timing
30-60 minutes before the largest meal
Competition status
Permitted — not on the WADA Prohibited List
Category
Branded Ingredients
Safety and side effects
Slendesta has been well tolerated in the trials conducted, with few adverse effects reported. It is derived from an ordinary food.
Being stimulant-free, it avoids the jitteriness, elevated heart rate and sleep disruption associated with caffeine-based appetite products, which is a genuine advantage for anyone sensitive to those.
Anyone sensitive to potato or nightshades should avoid it. Long-term data is limited. Speak to your doctor before use if you take regular medication.
Who should avoid it
Avoid if sensitive to potato or other nightshades. Speak to your doctor before use if you take regular medication or are under medical care. Long-term data is limited. Not established in pregnancy or breastfeeding.
This entry is provided for information only. Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle. Consult a qualified healthcare professional before use if you are pregnant, breastfeeding, taking medication or under medical supervision.
