Phytosterol

[4][5] They have a fused polycyclic structure and vary in carbon side chains and / or presence or absence of a double bond (saturation).

[12] The European Foods Safety Authority (EFSA) concluded that blood cholesterol can be reduced on average by 7 to 10.5% if a person consumes 1.5 to 2.4 grams of plant sterols and stanols per day, an effect usually established within 2–3 weeks.

[14] Based on this and other efficacy data, the EFSA scientific panel provided the following health advisory: "Plant sterols have been shown to lower/reduce blood cholesterol.

[15] The FDA has approved the following claim for phytosterols: For plant sterol esters: (i) Foods containing at least 0.65 g per serving of plant sterol esters, eaten twice a day with meals for a daily total intake of at least 1.3 g, as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease.

[19] Health Canada concluded that sufficient scientific evidence exists to support a relationship between phytosterol consumption and blood cholesterol lowering.

Based on this evidence, Health Canada approved the following statements for qualifying foods intended for hypercholesterolemic individuals: Primary statement: "[serving size from Nutrition Facts table in metric and common household measures] of [naming the product] provides X% of the daily amount* of plant sterols shown to help reduce/lower cholesterol in adults."

[22] Unlike the statins, where cholesterol lowering has been proven to reduce risk of cardiovascular diseases (CVD) and overall mortality under well-defined circumstances, the evidence has been inconsistent for phytosterol-enriched foods or supplements to lower risk of CVD, with two reviews indicating no or marginal effect,[23][4] and another review showing evidence for use of dietary phytosterols to attain a cholesterol-lowering effect.

[31] Phytosterol-containing functional foods were subject to postlaunch monitoring after being introduced to the EU market in 2000, and no unpredicted side effects were reported.

[32] A potential safety concern regarding phytosterol consumption is in patients with phytosterolaemia, a rare genetic disorder which results in a 50- to 100-fold increase in blood plant sterol levels and is associated with rapid development of coronary atherosclerosis.

Phytosterolaemia has been linked to mutations in the ABCG5/G8 proteins which pump plant sterols out of enterocytes and hepatocytes into the lumen and bile ducts, respectively.

Plant sterol levels in the blood have been shown to be positively, negatively or not associated with CVD risk, depending on the study population investigated.

[33][34][35][36][37][38][39][40] The link between plant sterols and CVD or CHD risk is complicated because phytosterol levels reflect cholesterol absorption.

Plant sterols and stanols, when compared head-to-head in clinical trials, have been shown to equally reduce cholesterol levels.