Plant Sterols
OTHER NAME(S): campesterol, plant sterol esters, plant sterols, phytosterols, sitosterol, stigmasterol
Overview
Plant sterols (phytosterols) are substances that are naturally found in many plants and plant-based foods. They are also available in dietary supplements. Plant sterol products are commonly used to lower cholesterol levels and reduce the risk of heart disease. Common side effects include loose stools or diarrhea. Before taking plant sterols, make sure to tell your health care provider about any health conditions you have or medicines you are taking.
Uses
What are plant sterols used for?
Plant sterols are commonly used to lower cholesterol levels and reduce the risk of heart disease.
Note: The FDA has not reviewed plant sterols for safety and effectiveness. Learn more about dietary supplements here.
How do plant sterols work (mechanism of action)?
Plant sterols, also known as phytosterols, are substances found in many plant-based foods. Some common sources of plant sterols include vegetable oils, vegetable spreads, nuts, breads, and cereals. Although many different sterols are found in plants, the most common forms are sitosterol and campesterol. Some foods and dietary supplements may list “plant sterol esters” on their labels. Plant sterol esters are made from natural plant sterols and have the same effects in the body.
The structure of a plant sterol is similar to, but not the same as, the structure of cholesterol. Because of their similar structures, plant sterols can block your body from absorbing some of the cholesterol in the foods that you eat. If cholesterol is not absorbed in your gut, it cannot increase the levels of cholesterol in your blood.
Over time, eating foods or taking supplements that contain plant sterols can help lower your cholesterol levels. If you have lower cholesterol levels, it may help reduce your risk of heart disease as you age. However, cholesterol is also made by your liver, so diet changes or plant sterol supplements may not be enough for some people to lower cholesterol levels enough to reduce the risk of heart disease.
You must eat at least 1.3-2 grams of plant sterols every day in order to lower your cholesterol levels over time. It is helpful to take or eat plant sterols at least two separate times each day, with different meals. This helps reduce the amount of cholesterol absorbed from each of these meals.
How should I store plant sterols?
You should store plant sterols according to the product label. Most dietary supplements should be kept in a cool, dry location that is out of the reach of children and pets and not in direct sunlight.
Side Effects
What are the most common side effects of plant sterols?
The most common side effects of plant sterols are loose stools or diarrhea. These side effects may vary depending on the dose you are taking or the specific product you are using. Tell your health care provider if you have any of these side effects that bother you.
There may be other side effects of plant sterols that are not listed here. Contact your health care provider if you think you are having a side effect of a supplement. In the U.S., you can report side effects to the FDA at www.safetyreporting.hhs.gov or by calling 888-SAFEFOOD (888-723-3366). In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.
What are the serious side effects of plant sterols?
While less common, the most serious side effects of plant sterols are described below, along with what to do if they happen.
Severe Allergic Reactions. Plant sterols may cause allergic reactions, which can be serious. Stop taking plant sterols and get help right away if you have any of the following symptoms of a serious allergic reaction.
- Breathing problems or wheezing
- Racing heart
- Fever or general ill feeling
- Swollen lymph nodes
- Swelling of the face, lips, mouth, tongue, or throat
- Trouble swallowing or throat tightness
- Itching or skin rash
- Bumps on the skin called hives that can be red, pink, white, or brown depending on your skin tone
- Nausea or vomiting
- Dizziness, feeling lightheaded, or fainting
- Stomach cramps
- Joint pain
Precautions
Who should not use plant sterols?
Allergies to Ingredients. People who are allergic to any of the following should not take plant sterols.
- Beta-sitosterol
- Campesterol
- Plant sterols
- Phytosterols
- Sitosterol
- Stigmasterol
- Any of the ingredients in the specific product
Your pharmacist can tell you all of the ingredients in the specific plant sterol products they stock.
Low-Sterol Diet.If your health care provider has told you to follow a diet low in plant sterols, you should not take plant sterol supplements. For example, if you have a rare condition called sitosterolemia (phytosterolemia), you should avoid plant sterol supplements.
What should I know about plant sterols before using it?
Plant sterols are naturally found in many plant-based foods and may be added to certain foods and spreads. Plant sterols are also sold as dietary supplements. These products cannot be marketed to treat or cure a disease. However, in the U.S., products that contain a certain amount of plant sterols are allowed to state that they may help reduce the risk of heart disease.
Read and follow the directions on the specific product you are taking, or take it as recommended by your health care provider.
Keep plant sterols out of the reach of children.
Plant sterols have the greatest effect on cholesterol when they are taken or eaten with foods that contain cholesterol. It is best to take plant sterol supplements along with a meal. When possible, plant sterols should be consumed with at least two separate meals each day.
The FDA has not tested plant sterols products to confirm that they contain the ingredients stated on their labels. Some dietary supplements have been tested by third-party organizations to confirm that they contain the ingredients listed on their labels and do not contain any harmful chemicals. Learn more about how to choose a safe dietary supplement product here.
What should I tell my health care provider before using plant sterols?
Tell your health care provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them know if plant sterols are right for you.
In particular, make sure that you discuss any of the following.
Soy Allergy.Some plant sterol supplements are made from soy. If you are allergic to soy, you may also have an allergy to products made from soy. But you may be able to take plant sterols that are made from other sources. Read the label carefully, and talk to your health care provider before taking plant sterol products made from soy.
Pregnancy. It is not known if or how plant sterols could affect pregnancy or harm a fetus. Tell your health care provider if you are pregnant or plan to become pregnant.
Breastfeeding. It is not known if plant sterols pass into breast milk. Tell your health care provider if you are breastfeeding or plan to breastfeed.
Interactions
Do plant sterols interact with foods or drinks?
There are no known interactions between plant sterols and foods or drinks. But plant sterols work best when taken with a meal, especially a meal that contains cholesterol.
It is unknown if drinking alcohol will affect plant sterols.
Do plant sterols interact with medicines (drug interactions)?
There are no known interactions between plant sterols and medicines. Always tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.
The interactions between plant sterols and medicines are not fully understood. As with most dietary supplements, the research on drug interactions with plant sterols is incomplete. Always check with your health care provider before taking plant sterols with any medicines.
Dosing
What should I do if I accidentally use too much plant sterols?
If you or someone else has used too much plant sterols, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.
Read the product label closely, and speak with a health care provider about how to take plant sterols safely. Do not take double or extra doses, even if you miss a dose.
References
- Code of Federal Regulations: “§ 101.83 Health claims: plant sterol/stanol esters and risk of coronary heart disease (CHD).”
- EFSA Journal: “Safety of a change of specifications of phytosterols/phytostanols as a novel food pursuant to Regulation (EU) 2015/2283,” “Safety of the extension of use of plant sterol esters as a novel food pursuant to Regulation (EU) 2015/2283,” “Scientific Opinion on the substantiation of health claims related to plant sterols and plant stanols and maintenance of normal blood cholesterol concentrations and maintenance of normal prostate size and normal urination pursuant to Article 13(1) of Regulation (EC) No 1924/2006.”
- National Cancer Institute NCI Dictionary of Cancer Terms: “plant sterol.”
- National Center for Complementary and Integrative Health: “High Cholesterol and Natural Products: What the Science Says.”
- Nutrients: “Plant sterols and plant stanols in cholesterol management and cardiovascular prevention.”
- StatPearls [Internet]: “Sitosterolemia (Phytosterolemia).”