Benefits
Blood pressure: olive extract trials, not AllOlive itself
AllOlive has not been tested in people. In a 6-week crossover trial in 60 pre-hypertensive men, a liquid olive leaf extract (136 mg oleuropein daily) lowered 24-hour systolic pressure about 3 mmHg more than control. But an 8-week trial of an olive leaf and fruit blend with similar oleuropein and hydroxytyrosol levels found no significant difference from placebo, and a 12-week capsule trial saw no change.
Oxidative stress markers: not improved in human olive extract trials
Hydroxytyrosol and oleuropein act as antioxidants in lab tests, but that has not translated into clear changes in people. In the 8-week leaf and fruit blend trial, oxidized LDL and malondialdehyde did not change compared with placebo, and in the 6-week olive leaf trial oxidized LDL did not change. AllOlive itself has no human antioxidant data.
Blood lipids: small changes in one olive leaf trial
In the 6-week crossover trial of a liquid olive leaf extract, total cholesterol, LDL cholesterol and triglycerides fell slightly more than on control. In the 8-week leaf and fruit blend trial, cholesterol fell in both the extract and placebo groups with no significant difference, and a 12-week capsule trial found no lipid effect. None of these used AllOlive.
Insulin sensitivity: one small olive leaf trial
In a 12-week crossover trial in 46 overweight middle-aged men, olive leaf extract capsules (51 mg oleuropein and 10 mg hydroxytyrosol daily) improved insulin sensitivity about 15 percent and pancreatic beta-cell responsiveness about 28 percent compared with placebo. Blood pressure and lipids did not change. This was a different olive leaf extract, not AllOlive.
Mechanism of action
Olive polyphenols and blood vessels (proposed)
Oleuropein and hydroxytyrosol are proposed to lower blood pressure by reducing oxidative stress and raising nitric oxide. In a small crossover study, a single dose of olive leaf extract (51 mg oleuropein, 10 mg hydroxytyrosol) lowered a pulse-wave stiffness index and IL-8 release from stimulated blood cells versus control, but longer trials are mixed.
Pentacyclic triterpenes (cell studies only)
AllOlive's distinguishing feature is its triterpene content. In a cell study co-authored by Natac scientists, a Natac olive triterpene extract combined with a Natac hydroxytyrosol extract improved survival of stressed rat heart cells and lowered superoxide, TNF-alpha and IL-6. Those were different Natac extracts, and no human data exist.
Clinical trials
Double-blind, placebo-controlled randomized trial (NCT04874961) at the University of Antwerp. Participants took three capsules daily for 8 weeks of Tensiofytol (Tilman): 334 mg olive leaf extract plus 106 mg olive fruit extract (labelled 100 mg oleuropein and 20 mg hydroxytyrosol), or placebo. Primary outcome: systolic blood pressure. Tilman partly funded the work through a university chair and supplied product and placebo. (Lauwers et al. 2026, PLoS One)
56 adults with systolic blood pressure of 130 mmHg or higher (mean age 54 and 58 in the two groups), 24 taking blood pressure medication; 54 analyzed.
Systolic pressure fell 8.3 mmHg on the extract and 7.3 mmHg on placebo, with no significant difference between groups (p = 0.760); diastolic pressure also did not differ. Cholesterol and LDL fell in both groups alike, oxidized LDL and malondialdehyde did not differ, and a slightly larger apo B drop (p = 0.043) was not treated as significant by the authors. The extract was well tolerated. This is a different product from AllOlive.
Randomized, double-blind, controlled crossover trial (NCT01796561) at Massey University. Participants took 20 mL daily of Comvita's liquid olive leaf extract (136 mg oleuropein, 6 mg hydroxytyrosol) or a polyphenol-free control for 6 weeks each, with a 4-week washout. Primary outcome: blood pressure. Comvita provided half the funding. (Lockyer et al. 2017, European Journal of Nutrition)
60 pre-hypertensive men aged 24 to 72 (mean BMI 26.7) who completed both phases.
Compared with control, 24-hour systolic pressure was 3.3 mmHg lower and diastolic 2.4 mmHg lower, with daytime readings about 4 and 3 mmHg lower. Total cholesterol, LDL and triglycerides fell slightly and IL-8 dropped. Oxidized LDL, CRP, other inflammatory markers, vascular function and glucose were not affected.
Randomized, double-blind, placebo-controlled crossover trial in New Zealand. Participants took olive leaf extract capsules (51.1 mg oleuropein, 9.7 mg hydroxytyrosol daily) or placebo for 12 weeks each, with a 6-week washout. Primary outcome: insulin sensitivity (Matsuda method). Comvita supplied the extract and placebo and co-funded the grant. (de Bock et al. 2013, PLoS One)
46 overweight men (mean age 46, BMI 28) at risk of metabolic syndrome.
Insulin sensitivity improved 15 percent (p = 0.024) and pancreatic beta-cell responsiveness 28 percent (p = 0.013) compared with placebo. There was no effect on 24-hour blood pressure, lipids, CRP, IL-8, TNF-alpha, body composition or carotid wall thickness, while IL-6 rose.