Fiber-Rich Foods Decrease Cholesterol
Increasing your fiber intake is probably the most important dietary change you can make. Of the strategies discussed in this article, only fiber has been shown to be effective during the treatment of CVD. The most likely reason for this is that most individuals undergoing treatment for CVD are already on drugs which very successfully lower cholesterol, so the addition of dietary changes doesn’t make the same impact it does before drug-therapy begins. However, this only serves to underline what a dramatic difference fiber-rich foods can make—even when cholesterol is well-controlled by drugs, fiber still works!
Fiber-rich foods can affect CVD risk both directly and indirectly. The most obvious, direct way fiber works is by lowering cholesterol levels. Most people don’t realize that the largest “dietary source” of cholesterol isn’t our food, but actually the bile our body produces to digest fat. Bile is formed in the liver from cholesterol, and most of it (90% or so) gets reabsorbed towards the end of our small intestine, allowing the cholesterol to re-enter circulation. The bile that doesn’t get absorbed is lost forever with along with the cholesterol it’s made from.
Soluble fiber binds the cholesterol-laden bile, causing it to be unavailable for reabsorption. When our diet is high in soluble fiber, significant amounts of cholesterol get excreted instead of reabsorbed, causing serum cholesterol levels to fall. Interestingly, new research suggests that some types of soluble fiber may also cause the body to produce less cholesterol. How fiber might accomplish this is unknown, but it is further good news for those who are trying to lower cholesterol levels!
If you have high cholesterol levels, adding a fiber supplement to your daily regime may be a good idea, as it will almost certainly lower your LDL cholesterol levels to a certain degree. Ideally, though, you should add plenty of soluble fiber-rich foods to your diet. Binding cholesterol is simply the most direct route through which fiber can lower your risk of CVD, but there are equally (if not more) important ways that whole fiber-rich foods mitigate risk as well.
Whole foods which are high in fiber also tend to be high in phytonutrients, antioxidants, and anti-inflammatory compounds, all of which may indirectly lower risk of CVD. A fiber supplement may work to lower cholesterol in one way, but consuming the foods whole is more powerful and will work in multiple ways.
Research consistently shows that populations with the highest consumption of vegetables, legumes, fruits, and whole grains have the lowest risk of CVD, and the reduction cannot be accounted for by the fiber content of these foods alone. For this reason, even if you take a fiber supplement or are going to start, it’s still incredibly important to add healthy whole food sources of fiber to your diet as well.