For centuries, turmeric root has been a staple of Asian medicine.
Turmeric features a trio of yellow-orange antioxidant compounds, collectively called curcumin.
Interest in curcumin rose when researchers noticed that curry-loving countries like India had lower rates of dementia and certain cancers.
Statistical links between copious consumption of a food and reduced risk for a disease can't prove a cause-effect relationship.
So researchers began to explore whether something in turmeric might have health-promoting powers.
Since then, the results of hundreds of lab studies – and a significant number of clinical studies – have suggested that curcumin supports or enhances immune, joint, mood, and brain health.
More recently, curcumin was shown to reduce risk markers for diabetes, and aid muscle recovery after exercise.
(To see our past reports on turmeric and curcumin, search our website for "curcumin”.)
And it's beginning to look like curcumin may also bring real benefits for cardiovascular health.
It came as a surprise when a 2014 review of five small clinical trials concluded that curcumin supplements did not produce consistent, significant improvements in blood cholesterol and triglyceride profiles (Sahebkar A 2014).
However, some of the trial participants did show significant drops in blood levels of total cholesterol, LDL cholesterol, and/or triglycerides.
And that evidence review did not include the positive results of a placebo-controlled Iranian clinical trial published later in 2014 (Panahi Y et al. 2014).
Those Iranian researchers found that curcumin did several very good things:
- Raised HDL cholesterol.
- Lowered non-HDL cholesterol.
- Lowered triglycerides, LDL cholesterol, and total cholesterol.
Now, the results of a new trial add more evidence that curcumin may be a significant heart-health ally.
Clinical trial finds curcumin benefits for risky blood fats and cholesterol
The new clinical trial comes from Iranian researchers at the Tehran Heart Center Hospital.
They recruited 33 cardiovascular patients for a randomized, double-blind, placebo-controlled study (Mirzabeigi P et al. 2015).
The participants were randomly assigned to one of two daily regimens for two months:
- Placebo capsules
- Curcumin capsules (four 500mg capsules; a total of 2,000mg of curcumin per day)
Importantly, the participants continued with whatever conventional therapies they had already been prescribed.
This means that any observed benefits from curcumin would be in addition the benefits of standard drug therapy.
Encouragingly, the curcumin group developed significantly lower blood levels of triglycerides and LDL cholesterol, compared to their levels at the outset of the study.
Better yet, the curcumin group also showed a significant drop in their VLDL cholesterol levels (see "What are the real heart risk factors?", below).
There were no statistically significant changes (up or down) in the curcumin group's blood levels of HDL cholesterol levels or C-reactive protein (a marker of inflammation)
As the Iranian team wrote, "According to the results, curcumin seems to be a potential candidate for decreasing cholesterol and triglyceride levels.” (Mirzabeigi P et al. 2015)
Choose the right curcumin
Unfortunately, standard curcumin supplements are very poorly absorbed, and probably offer little if any benefit.
In this case, the Iranian researchers gave their subjects a supplement that combines curcumin with piperine.
What are the real heart risk factors?
For decades, doctors accepted and promoted the fallacy that dietary cholesterol and saturated fat cause heart disease.
That hypothesis – and the evidence upon which it was based – have now been largely discredited.
We should note that a small percentage of people possess genetic profiles that render dietary cholesterol a real risk factor.
And certain blood fat profiles are clearly linked to a risk for heart disease: high levels of non-HDL cholesterol, triglyceride-packed VLDL cholesterol, triglycerides, and dense or oxidized cholesterol.
(The best way to lower VLDL cholesterol is to lower your blood triglyceride levels, not your intake of saturated fat or cholesterol.)
Fish oil, exercise, and diets low in sugars and refined carbs can help lower blood levels of triglycerides, as can maintaining a healthy weight and avoiding diabetes.
Other heart-risk factors include smoking, sedentary lifestyles, chronic inflammation, and high intakes of sugars and refined carbohydrates. such as white flour.
As to inflammation, the standard American diet is overloaded with food factors that, when consumed in excess, promote inflammation.
These include refined sugars and carbohydrates, and the omega-6 fats that abound in cheap vegetable oils (corn, soy, safflower, sunflower, cottonseed: see Know Your Omega-3/6 Numbers
Sadly, the standard American diet is high in risky food factors but low in ones that that reduce inflammation and improve blood-fat profiles … such as the fibers and antioxidants in plant foods, and the omega-3 fatty acids in seafood.
The take away message for heart health is pretty simple.
Eat a diet rich in whole plant foods, seafood, and modest amounts of organic meats and poultry.
And as health insurance, enjoy plenty of curry – without the cheap vegetable oils that restaurants often use to make curry sauces – and take fish oil and a well-absorbed form of curcumin
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