One of the most amazing clinical studies ever performed has been hidden away behind a paywall for more than a decade. When I first stumbled upon this clinical pearl two years ago, in the form of the publicly indexed abstract on pubmed.gov, my jaw nearly dropped.
“Pomegranate juice consumption resulted in a significant IMT [intima-media thickness] reduction, by up to 30 percent, after 1 year,” reads the most eye-opening line in the study’s abstract.
Pomegranate Juice - Reversing Atherosclerosis
The intima media is the middle portion of the arteries that becomes inflamed and fills with plaque comprised of oxidized fats, immune cells, and their debris, in the condition known colloquially as “blocked arteries,” or clinically as “atherosclerosis.” As the intima media grows thicker, less space is available for the blood contents to move through the opening (lumen) of the arteries. When the arteries eventually close or are blocked, catastrophic injury or death may follow.In fact, if a simple daily dietary intervention is capable of regressing or reversing the underlying disease process in millions of fatal cardiac cases, it would seem highly unethical not to use it.
The Pomegranate ‘Artery-Cleaning’ Clinical Trial
The study consisted of 19 patients, five women and 14 men, aged 65 to 75, who were non-smokers. They were randomized to receive either pomegranate juice or a placebo. Ten patients were in the pomegranate juice treatment group and nine patients who didn’t consume pomegranate juice were in the control group. Both groups were matched with similar blood lipid and glucose concentrations, blood pressure, and with similar medication regimens, which consisted of blood-pressure lowering (e.g. ACE inhibitors, beta-blockers, or calcium channel blockers) and lipid-lowering drugs (e.g. statins).
The 10 patients in the treatment group received 8.11 ounces (240 ml) of pomegranate juice per day, for a period of one year, and five out of them agreed to continue for up to three years.
The remarkable results were reported as follows:
“The mean intima media thickness of the left and right common carotid arteries in severe carotid artery stenosis patients that consumed pomegranate juice for up to 1 year was reduced after 3, 6, 9 and 12 months of pomegranate juice consumption by 13 percent, 22 percent, 26 percent, and 35 percent, respectively, in comparison to baseline values.”
You can only imagine what would happen if a pharmaceutical drug was shown to reverse plaque buildup in the carotid arteries by 13 percent in just three months! This drug would be lauded as a life-saving miracle drug, and not only would be promoted and sold successfully as a multi-billion dollar blockbuster, but discussion would inevitably follow as to why it should be mandated.
While these results are impressive, if not altogether groundbreaking for the field of cardiology, they may be even better than revealed in the stated therapeutic outcomes above.
When one factors in that the carotid artery stenosis increased 9 percent within one year in the control group, the pomegranate intervention group may have seen even better results than indicated by the measured regression in intima media thickness alone. That is, if we assume that the pomegranate group had received no treatment, the thickening of their carotid arteries would have continued to progress like the control group at a rate of 9 percent a year, i.e., 18 percent within two years, 27 percent within three years.
3 Ways Pomegranate Heals the Cardiovascular System
The researchers identified three likely mechanisms of action behind pomegranate’s observed anti-atherosclerotic activity:Antioxidant Properties
Subjects receiving pomegranate saw significant reductions in oxidative stress, including decreases in autoantibodies formed against ox-LDL, a form of oxidized low-density lipoprotein associated with the pathological process of atherosclerosis.Decreases in oxidative stress were measurable by an increase in the blood serum enzyme paraoxonase 1 (PON1) of up to 91 percent after three years; PON1 is an enzyme whose heightened activity is associated with lower oxidative stress.
All of this is highly relevant to the question of pomegranate’s anti-atherosclerotic activity because of something called the lipid peroxidation hypothesis of atherosclerosis, which assumes that it’s the quality of the blood lipids (i.e., whether they are oxidized/damaged or not), and not their quantity alone that determine their cardiotoxicity/atherogenicity.
Blood Pressure Lowering Properties
The intervention resulted in significant improvement in blood pressure: the patient’s systolic blood pressure was reduced by 7 percent, 11 percent, 10 percent, 10 percent, and 12 percent after 1, 3, 6, 9, and 12 months of pomegranate consumption, respectively, compared to values obtained before treatment.Plaque Lesion Stabilization
Because two of the 10 patients on pomegranate juice (after three and 12 months) experienced clinical deterioration, carotid surgery was performed and the lesions were analyzed to determine the difference in their composition to those who didn’t receive pomegranate. The researchers noticed four distinct positive differences in the composition of the pomegranate-treated lesions:Essentially, these results reveal that not only does pomegranate reduce the lesion size in the carotid arteries, but “the lesion itself may be considered less atherogenic after PJ consumption, as its cholesterol and oxidized lipid content decreased, and since its ability to oxidize LDL was significantly reduced.”
This finding is quite revolutionary, as presently, the dangers of carotid artery stenosis are understood primarily through the lesion size and not by assessing the quality of that lesion.
This dovetails with the concept that the sheer quantity of lipoproteins (i.e. “cholesterol”) in the blood can not accurately reveal whether those lipoproteins are actually harmful (atherogenic); rather, if lipoproteins are oxidized (e.g. ox-LDL) they can be harmful (or representative of a more systemic bodily imbalance), whereas non-oxidized low-density lipoprotein may be considered entirely benign, if not indispensable for cardiovascular and body-wide health.
Indeed, in this study the researchers found the pomegranate group had increased levels of triglycerides and very low-density lipoprotein, again, underscoring that the anti-atherosclerotic properties likely have more to do with the improved quality of the physiological milieu within which all our lipoproteins operate than the number of them, in and of itself.