Effects of chocolate on cardiovascular health

If you're anything like me, you go out of your way to look for excuses to eat chocolate. If so, this could be exactly what you're looking for!

A study published in 2008 reveals that regular consumption of chocolate bars containing plant sterols and cocoa flavanols as part of a low-fat diet may support cardiovascular health by lowering cholesterol and improving blood pressure [1]. 32 women and 17 men were randomized into two groups and followed for eight weeks in total. Both groups consumed one chocolate bar two times per day containing cocoa-flavanols (CF), but one group's chocolate bar also contained plant sterols (PS). The group receiving the chocolate bar without PS was considered the control group. The chocolate bars used in the study were CocoaVia from Mars Inc., therefore, everything else but the amount of PS was the same for both groups; the PS chocolate bar simply contained added PS. The diet and physical activity of each participant was monitored to further ensure the only changing factor was the PS level in the chocolate. Participants were required to follow a diet within the guidelines of the AHA (American Heat Association). After four weeks, the groups switched chocolate bars and continued for an additional four weeks. 


Researchers measured blood pressure every two weeks and serum lipids along with other cardiovascular disease markers at the starting period, week four and week eight. The main factor that changed during this study was the LDL ('bad') cholesterol level. It was also noted that the weight of the participants did not change considerably during the course of the study (within 3.5% either higher or lower than their baseline weight). Regular consumption of the PS-containing chocolate bar resulted in reductions of 3% and 5.3% in serum total and LDL cholesterol, respectively. It was concluded that the consumption of CF in both chocolate bars resulted in lowered systolic and diastolic blood pressure. At the end of the study, it was found that systolic blood pressure was reduced by 5% of the baseline pressure and diastolic pressure by 2.2%. 

As the discussion of the article states, "this study demonstrates that, in the context of a balanced AHA diet, "An Eating Plan for Healthy Americans," the regular consumption of cocoa flavanol-containing chocolate bars with added PS can significantly lower serum total and LDL cholesterol levels over the course of 4 weeks." Since the bar without PS did not lower cholesterol levels, it must be attributed to the addition of PS in one's diet. Cocoa and cocoa-containing products, such as chocolate, contain flavanols which have been shown to improve one's health benefits, especially CVD. Remember to eat a balanced and healthy diet to ensure your heart is getting all the nutrients it needs. Stay healthy and indulge your sweet tooth with a chocolate bar containing CF and PS!

Does (eating) cholesterol cause cardiovascular disease?

There has been much speculation about whether or not high levels of cholesterol increase the risk of cardiovascular disease. Some studies show a direct correlation of increased cholesterol with increased risk of cardiovascular disease. While some say this relationship is much more complex, these studies suggest that the opposing studies are over-exaggerating [1]. Therefore, it can be difficult to know exactly what to believe on this controversial topic.


Cholesterol is one of the body's lipids. It's an essential building block for the structure of cells, steroid hormones and vitamin D.  An individual's cholesterol level depends on how their body makes cholesterol in the liver as well as their diet. There are two types of cholesterol produced in the liver; the 'good' kind or high-density lipoprotein (HDL) and the 'bad' kind or low-density lipoprotein (LDL) [2].


LDL can stick to artery walls, causing the arteries to narrow, which eventually blocks oxygen transport and consequently causes a heart attack. Some studies have found that LDL levels are more predictive of CVD than total cholesterol levels alone, which makes sense since HDL actually protects against the hardening and narrowing of the arteries [3]. These studies also suggest that it's not so much the dietary cholesterol as it is the individual's cholesterol synthesis (or blood cholesterol) that has an impact on the risk of CVD. One study showed that consumption of up to seven eggs per week (a food high in cholesterol) does not have significant effects on blood cholesterol levels, and would therefore not have a significant impact on the risk of CVD [4].


However, other studies have shown that some individuals, such as people older than 65 and middle-aged women, with elevated cholesterol levels are clearly at increased risk of coronary disease [5]. A correlation in a specific age group concludes that their bodies must be functioning in a similar way, with regards to how they synthesize cholesterol. Researchers measured LDL cholesterol levels and saw that higher levels predicted coronary heart disease in the two people groups (older people and middle-aged women). It was recommended to increase physical activity, lose excess weight, and follow a diet low in saturated fat and cholesterol in order to reduce the risk of CVD.


I suppose the controversy is exactly how one acquires high cholesterol rather than if it causes CVD, since both sides are in agreement that high levels of cholesterol (specifically LDL levels) are a risk factor for CVD. One side states it has more to do with how the body manufactures cholesterol and the other says it depends on how much cholesterol and saturated fat you consume. I think that it depends on how your body processes cholesterol, since the studies that have proved this (like the egg study) are more recent and seem to be much more thorough. Hopefully this post has encouraged you to do some research of your own on cholesterol and come to your own conclusion! Remember: cholesterol is an essential nutrient for our bodies, so don't cut it out of your diet completely. However, it is a good idea to minimize the amount of LDL cholesterol you eat. Continue to keep your heart healthy and happy!