What are plant sterols?
Plant sterols, also known as phytosterols, are natural compounds found in plants that have a chemical structure similar to cholesterol. When consumed, they compete with cholesterol for absorption in the intestines. By blocking some of the cholesterol from being absorbed, they help to lower total and LDL ("bad") cholesterol levels in the blood. Humans naturally consume a small amount of sterols in a typical diet, but larger quantities from fortified foods or supplements are needed to achieve a therapeutic effect. Fortified products, which contain higher, standardized amounts of these compounds, have become a common way for many people to boost their intake for cardiovascular benefits.
Naturally high sources of sterols
While the amount of naturally occurring sterols in single food items is generally too low to have a significant cholesterol-lowering effect on its own, a diet rich in a variety of these plant-based foods can contribute to a healthy heart. The most concentrated sources are found in certain oils, nuts, and seeds. Key examples of naturally high sources of sterols include:
- Vegetable oils: Corn oil, wheat germ oil, and sesame oil contain some of the highest concentrations of plant sterols among vegetable oils. Olive oil is also a good source.
- Nuts and seeds: Pistachios, almonds, peanuts, macadamia nuts, and sunflower seeds are packed with sterols and healthy fats. Sesame and pumpkin seeds are also excellent sources.
- Legumes: A variety of legumes, including peas, beans, and lentils, contain a moderate amount of plant sterols. Soybeans and kidney beans are notable examples.
- Whole grains: Whole grains like wheat germ, rice bran, and brown rice contain phytosterols. Adding wheat germ to cereals or baked goods is a simple way to increase intake.
- Fruits and vegetables: A range of fruits and vegetables contain smaller amounts of sterols. Avocado, Brussels sprouts, broccoli, and oranges are some examples. Apples and tomatoes also contribute.
Fortified foods with added sterols
To achieve the recommended daily intake of 1.5 to 3 grams of plant sterols for cholesterol reduction, incorporating fortified foods is often necessary. These products are specially engineered to contain a higher dose than is found naturally. Common fortified options include:
- Margarines and spreads: Some buttery and olive spreads are fortified with plant sterols or stanols. A few servings daily can help meet the target intake.
- Yogurts and yogurt drinks: Many mini yogurt drinks and yogurt pots are enriched with sterols or stanols, providing a convenient dose in a single serving.
- Juices: Certain brands of orange and fruit juices are fortified with plant sterols to help lower cholesterol.
- Milk: Fortified milk, including some dairy and dairy-free options, offers another way to incorporate these compounds into your diet.
- Cereals and granola bars: Some breakfast cereals and snack bars now include added plant sterols to boost their cholesterol-lowering potential.
Sterols vs. statins: A comparison
| Feature | Plant Sterols/Stanols | Statins |
|---|---|---|
| Mechanism | Block cholesterol absorption in the gut. | Reduce the amount of cholesterol produced by the liver. |
| Availability | Over-the-counter in fortified foods and supplements. | Prescription medication. |
| Effectiveness | Can lower LDL cholesterol by 7-12% when taken consistently. | Typically more potent, offering greater reductions in LDL cholesterol. |
| Add-on therapy | Safe to use alongside statins, providing an additive cholesterol-lowering effect. | Prescription only; can be combined with sterols for greater efficacy. |
| Long-term evidence | Insufficient long-term evidence on reduction of heart attack/stroke risk. | Strong evidence for reducing the risk of heart attack and stroke. |
| Cost | Can be more expensive than non-fortified alternatives. | Price varies; may be covered by insurance. |
How to effectively incorporate sterols into your diet
To get the maximum benefit from sterols, it is crucial to consume them correctly. They work best when eaten with a meal, as this helps them mix and bind with food in the intestines, improving absorption. Experts recommend a daily intake of 1.5 to 3 grams, ideally spread throughout the day. However, more is not necessarily better, as consuming more than 3 grams daily offers little additional benefit. Always check food labels for specific serving sizes and sterol content. Because sterols can interfere with the absorption of some fat-soluble vitamins (like beta-carotene), it is wise to maintain a diet rich in fruits and vegetables. If relying on supplements, ensure they are taken with a meal containing some healthy fat.
Conclusion
Understanding what foods are high in sterols is a valuable step towards managing cholesterol and promoting heart health. While a variety of plant-based foods, including oils, nuts, seeds, and whole grains, contain natural sterols, fortified products like spreads, yogurts, and juices offer a more concentrated dose for therapeutic effects. Integrating these foods into a balanced diet, along with other healthy lifestyle choices, can be an effective strategy, especially for those with elevated cholesterol levels. It is important to remember that fortified foods are not a replacement for prescribed medication but can work in conjunction with them to support cardiovascular well-being. For the best approach, consider discussing your dietary plan with a healthcare provider or a registered dietitian.
