Atherosclerosis is a condition characterized by hardening of the arteries. The development of severe atherosclerosis can cause severe complications like a myocardial infarction (heart attack).
Past research has suggested that maybe vitamin D can help atherosclerosis in a few different ways. For one, researchers are interested if vitamin D might be able to make your arterial walls smoother. And two, vitamin D reduces inflammation, which is involved in atherosclerosis, too.
In the current study, researchers wanted to look at vitamin D’s role in the arteries immediately after high intake of dietary fat. Taking a look at vitamin D in this circumstance can help researchers gain greater perspective of vitamin D’s role in atherosclerosis and cardiovascular disease.
After you eat a meal, your body starts to digest and distribute the food and nutrients you consumed. This is called the postprandial state. When in the postprandial state after a fatty meal, the fatty acids are delivered to your liver and can be returned to the blood as low-density lipoproteins (LDL).
A high amount of lipoproteins in the postprandial state can make your body activate an inflammatory response, sending white blood cells into your blood stream. This can increase the adhesion of the arterial walls. So, in general, postprandial inflammation is considered to be pro-atherogenic and unwanted.
To see how vitamin D affects the arteries in the high-fat intake postprandial state, researchers recruited 12 participants (6 men and 6 women) and administered them a fat-loading test (intake of 50 grams of fat per square meter of body surface area via oral intake of cream). The researchers monitored their arteries every two hours for the next eight hours to determine changes in their arterial elasticity and inflammation brought on by the increased fat intake.
After these eight hours, the participants were all given 100,000 IU of vitamin D3. One week later, the participants underwent a second fat-loading test and a second monitoring.
The researchers wanted to know if an increase in vitamin D levels led to a change in stiffness and inflammation in the arteries. Here’s what they found:
- Vitamin D supplementation led to a non-significant reduction in arterial stiffness (p=0.042).
- In women, vitamin D supplementation led to a significant reduction in monocytes (p=0.016) and neutrophils (p=0.014), both of which are white blood cells that are activated in response to inflammation.
The researchers had mixed conclusions:
“Vitamin D3 increased postprandial arterial elasticity in men and women probably by a direct effect on the arterial wall.”
They further added:
“Vitamin D3 reduced postprandial leukocyte activation exclusively in women and therefore, could not fully explain the improved postprandial arterial elasticity.”
These initial results will be followed up by a randomized controlled trial currently being conducted by the same department at Sint Franciscus Gasthius hospital in the Netherlands. While these results suggest vitamin D may play role in improving arterial elasticity and reducing the inflammatory response after a fatty meal, it won’t be until the completion of this randomized controlled trial that we can truly see if there are any effects of vitamin D supplementation on these markers.