Phytosterols are a type of nutrient that’s supposed to be very good for your health. They're found in dairy products, nuts, vegetables, or whole grain products, and are said to have cholesterol-lowering effects. However, scientific evidence suggests that they may not be as beneficial as believed.
Phytosterols: A quick overview
Phytosterols is the general descriptive term for plant sterols and stanols, and they are natural steroids found in plants. They have molecules very similar to cholesterol, coming from plant membranes. Consider them as the plant’s cholesterol, if you will.
People generally get their intake of phytosterols from consuming vegetables that contain them, but despite their resemblance to cholesterol, your body metabolizes them differently. Phytosterols are found in foods such as legumes, vegetables, fruits, seeds, or even nuts. Vegetable oils have a very high phytosterol content, but since they are now an ingredient in many processed foods, you are most likely consuming way more than you should. People who consume a lot of cereal grain will also have a large intake of phytosterols.
But one of the foods that’s most rich in this type of cholesterol is margarine. Oddly enough, margarine is often labeled as being able to lower cholesterol, but this assertion isn’t entirely true.
Phytosterols can only be obtained from food, as your body doesn’t naturally produce them. There are currently more than 40 different types of plant sterol, but the most abundant ones are stigmasterol, campesterol, and beta-sitosterol.
Phytosterols and heart health
Phytosterols can lower cholesterol levels, and there is a lot of evidence to suggest that. By consuming a maximum of three grams of phytosterols for three to four weeks every day, you can reduce LDL cholesterol levels by about 10 percent. That’s because this plant cholesterol is healthier compared to animal cholesterol, so phytosterols are efficient for people with high cholesterol levels, regardless of whether they are following a medication-based treatment or not.
It is believed that phytosterols prevent your body from absorbing too much cholesterol by competing for the same enzymes. However, there is no scientific evidence that link phytosterols with a decrease in the risk of heart disease.
The same statement is valid for heart attacks — while having high cholesterol normally increases the risk of a heart attack, evidence does not suggest that phytosterols can lower that risk.
A large Scandinavian study revealed how people with a diet rich in phytosterols were more likely to get a heart attack. Other studies conducted on mice showed that there is an increased plaque buildup if there is a high concentration of phytosterols in the blood.
Other benefits of phytosterols
There is some evidence which points to the idea that phytosterols reduce the risk of cancer, particularly ovarian, breast, lung and stomach types. These assertions are based mostly on results coming from animal studies, which have shown a decrease in the growth and spread of tumors. Since there are no human studies to support the evidence, there is still a lot of skepticism on the matter.
On a general note, you would have to consume a large quantity of phytosterols in order for them to make a significant impact on your cholesterol levels. Alternatively, people can purchase phytosterols supplements in store, but their effectiveness is rather questionable.
There are researchers who suggest that the manufacturing process for making phytosterol supplements renders them biologically inactive, which would mean that they are not at all efficient in reducing cholesterol levels.
When you consume phytosterols found in foods such as spreads and soybeans, you will get a much more significant intake, as the ingredients are biologically active, and therefore efficient in lowering cholesterol.
But because of other disadvantages (such as margarines being rich in calories), the most important thing is balance. The key takeaway here is that phytosterols that come from dietary sources are much more efficient in lowering cholesterol compared to supplements which undergo processes that change the molecule structure, and can be rendered inefficient.
The link between phytosterols and cholesterol is pretty clear, but that doesn’t make things less complicated, considering that the medical world has divided opinions on whether these products should be included in a person’s diet or not. So far, evidence suggests that phytosterols are good because they are metabolized differently compared to cholesterol coming from animal sources, meaning that you are less likely to end up with artery blockage and plaque buildup. Even so, the long-term effects of consuming phytosterols have yet to be discovered, so if you want to include them in your diet, consult with your doctor.