Pine bark extract shaves points off blood sugar, pressure and cholesterol

Cardiometabolic health covers the cluster of measures that predict heart disease and diabetes risk: blood sugar, blood pressure, cholesterol and body weight. Pycnogenol is a widely sold supplement, and individual clinical trials testing it against these measures have produced controversial, conflicting results. When single trials disagree, pooling them is the standard way to find out whether a real signal sits underneath the noise. That is the question this review set out to answer: does pycnogenol actually shift the numbers that matter for cardiometabolic disease?

The researchers systematically searched the PubMed, Scopus and ISI Web of Science databases up to October 2018 for randomised controlled trials that evaluated the effects of pycnogenol on cardiometabolic parameters. Trials where people were assigned at random to pycnogenol or a comparison condition were eligible. They then pooled the results using random-effects statistical models, calculating the weighted average difference between pycnogenol and control groups for each outcome. In total, 24 trials covering 1594 participants met the criteria and went into the analysis.

Pycnogenol was linked to a set of small but statistically significant improvements. Fasting blood glucose fell by an average of 5.86 mg/dl and glycated haemoglobin by 0.29 percentage points. Systolic blood pressure dropped by 2.54 mmHg and diastolic by 1.76 mmHg. Body mass index edged down by 0.47 kg/m2, LDL cholesterol fell by 7.12 mg/dl, and HDL cholesterol rose by 3.27 mg/dl. Every individual effect is modest; the notable point is that all seven markers moved in the favourable direction at once.

Before this pooling, the trial literature on pycnogenol was openly described as controversial, with studies pointing in different directions. This analysis suggests a consistent, if small, benefit across the cardiometabolic profile, which strengthens the case that something real is happening. It does not close the question. The authors explicitly call for further well-designed randomised trials to evaluate long-term effects and to work out the optimal duration of use and dosage, none of which this analysis could establish.

This is a reason to think pycnogenol may nudge several cardiometabolic markers in a helpful direction, rather than proof that it prevents disease. The improvements are small in absolute terms: a few points of blood pressure and a few mg/dl of cholesterol. Anyone weighing up the supplement should know that the evidence base is still maturing, the right dose and duration are unresolved, and no long-term outcome data exist yet. It is a finding to watch, not a finished story.