Phylosterols

Both plant sterols and plant stanols are considered to be phylosterols.  Phylosterols are an essential component of all plant membranes.  Interestingly, plant sterols and stanols have a similar resemblance to the chemical structure of cholesterol.  Also, plant sterols and stanols are responsible for the same primary cellular functions in plants that cholesterol is responsible for in humans.

Sterols

Sterols are available through many of the foods we eat; vegetable oil, seeds, nuts, fruits, vegetables, cereals, legumes, and a variety of other plant sources.  Cholesterol is a sterol.  Cholesterol is important to the human body for a variety of factors, including acting as a secondary messenger in developmental and cellular signaling, in addition to forming part of cellular membranes.

Cholesterol levels must be maintained and regulated within the blood system to prevent the occurrence of blockages which can lead to certain conditions, such as a heart attack.  Plant sterols have been associated with the capability of blocking cholesterol absorption within the intestinal system.  If the cholesterol is not absorbed, it is not used and excreted.  This can lead to an overall decrease in cholesterol levels.

Stanols

Stanols, chemically known as stanol esters, are specific chemical compounds that have been correlated with the capacity to decrease overall levels of low density lipoproteins (LDL, “bad” cholesterol) when ingested on a regular basis.  Sterols are located in plants, and available from a variety of foods; vegetables, nuts, cereals, legumes, seeds, fruits, vegetable oil, and a variety of other plant sources.

How Much Sterols and Stanols?

While exact numbers have not been established with accuracy, it is typically recommended that 2 grams of sterols or stanols in one day can provide the wanted effects of lowered cholesterol.  However, the matter of delivery is still debated by many experts.  It is agreed that obtaining sterols and stanols from natural foods is the best method of delivery.

However, there are supplements available in addition to everyday foods.  It should be kept in mind that supplements are named because they are supplemental.  Supplements can not correct bad diets and lifestyle choices.  Rather, they are meant to be taken in addition to healthy choices as a sort of insurance, giving the body the extra nutrients it needs that are not obtained through the healthy diet.

The Evidence: Lowering Cholesterol with Sterols and Stanols

There does exist preliminary evidence supporting that sterols and stanols, when provided in adequate amounts, are associated with overall decreases in total cholesterol and low density lipoproteins, in addition to increases in high density lipoprotein levels.  However, this evidence is still preliminary, and more research must be conducted to confirm or deny these studies, while providing exact molecular mechanisms for how these sterols and stanols accomplish lowered cholesterol.

The consumption of sterols and stanols is accomplished through eating a variety of fruits and vegetables.  Fruits and vegetables are a considerable part of a healthy diet, providing many vitamins, nutrients, minerals, and essential amino acids.  It is also possible to lower total cholesterol and lower “bad” cholesterol while increasing “good” cholesterol by the addition of a healthy diet.

Resources:

http://www.ific.org/publications/factsheets/sterolfs.cfm

http://www.clevelandclinic.org/heartcenter/pub/women/sterolstanol.htm

http://www.medicinenet.com/script/main/art.asp?articlekey=56305