Cardiovascular disease is the leading cause of morbidity and mortality in adults. The majority of cardiovascular disease results from atherosclerosis. Millions of people take medications to try to combat or prevent atherosclerosis. So why don’t we hear about the powerful effect pomegranates can have on our arteries and cardiovascular health?
Following on from last week’s blog post about the general health benefits of pomegranates, this week I think you’ll be impressed with pomegranate’s impact on cardiovascular health and atherosclerosis.
What is atherosclerosis?
Twenty or so years ago, we thought that atherosclerosis was all about cholesterol being deposited on the inside surface of our arteries to form a plaque. The idea was that this deposit increased in size, narrowing the artery and eventually blocking blood flow. It is like a clogged up pipe. All we needed was a “roto-rooter” for our arteries, so they said!
Nowadays, although you’ll still frequently hear the clogged pipe idea mentioned, we know better. We have a better understanding of the mechanisms, but there are still several hypotheses.
There is considerable evidence connecting oxidative stress to atherosclerosis and cardiovascular disease. Oxidative stress can damage LDL (low-density lipoprotein), leading to oxidized LDL. This ox-LDL is pro-inflammatory and is taken up by immune cells causing an influx of cells into the artery wall. You can see this illustrated below. It is the oxidized LDL that is the issue, not plain old LDL. Oxidative stress oxidizes LDL leading to a cascade of inflammatory factors, ultimately resulting in inflammation, a narrowing of the artery, and thrombus formation:
A key difference in our current understanding is that atherosclerosis is a thickening of the artery wall not cholesterol sticking to the inside of the artery. The plaque (cells + lipids) is in the wall of the artery, not just something inside the vessel.
Enough complex scientific theories…..
Now let’s take a look at a study looking at the effects of pomegranate juice and atherosclerosis.
1. Pomegranate juice effects on atherosclerosis looking at carotid artery thickness.
Take a look at this study design and results on the powerful effects of 8oz pomegranate juice daily for a year. Ref: http://alturl.com/afu5v
(Now you understand why I explained about cell wall thickness earlier!)
The study size was small with only 10 test and 9 control patients. But even if a study is small, it doesn’t mean we have to reject it. We just also need to consider how the results of this study fit into the body of other research data that is out there. So let’s briefly look at some other cardiovascular studies with pomegranate.
2. Pomegranate juice effects on arterial plaque
Looking at the carotid artery, one study found that men drinking pomegranate juice for a year had a 30% decrease in arterial plaque. Those who didn’t drink pomegranate juice had a 9% increase in arterial plaque.
3. Pomegranate juice effects on blood flow to the heart and angina
UCSF study looked at patients with heart disease. Nearly half had suffered heart attacks, most had high blood pressure and nearly all had high cholesterol levels. They were all taking several drugs, including statins, blood thinners, and blood pressure medication. For three months, one group drank 8oz pomegranate juice a day. The others drank a placebo. After three months, the group drinking pomegranate juice had a 17% increase in blood flow to the heart. The placebo group had an 18% decrease in blood flow. They also found that episodes of angina decreased 50% in the pomegranate juice drinking group. Angina episodes increased 38% in the placebo group.
4. Pomegranate juice effects on systolic blood pressure
A study looked at the effect of supplementing 50ml pomegranate daily on hypertension. Here are the changes in systolic blood pressure.
1 month – 7% drop in systolic bp
3 months – 11% drop in systolic bp
6 months – 10% drop in systolic bp
9 months – 10% drop in systolic bp
12 months – 12% drop in systolic bp
There are plenty more studies out there. If this has piqued your interest, look further by searching for pomegranate and atherosclerosis. What is important is the consistency of results. Yes, some of the studies may be small but the results are consistent and support mechanisms of disease.
How is pomegranate juice having these effects?
Pomegranates are very rich in polyphenols which are able to scavenge free radicals, thus reducing oxidative stress.
In addition, pomegranates are also seen to activate the production of an enzyme called Paraoxonase 1 (PON1). This enzyme is seen to inhibit the oxidation of LDL. PON1 activity is typically reduced in people with CVD and diabetes as it is inactivated by oxidized lipids. Polymorphisms in the gene that make PON1 also affect the activity of the enzyme, so if you have had your genes tested, take a look to see if you have a polymorphism in PON1 that could be reducing the enzyme.
Interestingly, in Study 1 above, they measured PON1 enzyme levels. Pomegranate juice intake resulted in an 80% increase in PON1 activity at 1 year.
Pomegranate juice for cardiovascular health
I know we’ve covered a lot here, from the basics of atherosclerosis to how pomegranate ‘works’. But hopefully, the message is clear.
These studies show impressive effects in people with cardiovascular disease. Drinking a glass of pomegranate juice a day seems like a potentially low risk:high benefit approach to cardiovascular disease. If a drug were having these same effects, we’d all hear about it from the pharmaceutical companies!
Have you had your genes tested? Take a look at PON1 to see if you have a polymorphism. If so, the benefit of pomegranate juice and reducing oxidative stress may be even more important for you. It’s an easy nutrigenomic strategy.
But, maybe you are thinking that you don’t have CVD so how does this apply to you? Remember, as we saw in the first diagram, the stages of atherosclerosis begin with no symptoms and can start at an early age and take years to progress. So while we may not have looked at pomegranate juice in specific terms of prevention of disease, what do you think? Should it be part of your diet?
As always, please remember that not one thing does it all. If you eat a bad diet, smoke, don’t exercise, don’t take care of yourself and just add pomegranate juice to that, you are not going to get healthy. Also, pomegranate isn’t “THE” single answer. What these studies suggest is that including anti-oxidant rich foods, like pomegranate, in our diet can have significant cardiovascular benefits. Get eating and drinking a rainbow! Cheers!🍷