Reader question: What’s the evidence for plant sterols reducing cholesterol levels? Should I be Actimel-ing once a day as part of a healthy diet?


What’s the evidence for plant sterols reducing cholesterol levels? Should I be Actimel-ing once a day as part of a healthy diet?

– Baffled in Blackheath

I assume that you don’t care about your cholesterol per se, but rather your risk of developing cardiovascular disease (CVD).

Here is complete list of the randomized clinical trials relating plant sterols to CVD:



That’s not an error. There has never been a study done to directly test the link between plant sterols and CVD. There is evidence that plant sterols lower LDL cholesterol (which I refer to as ‘depleted liver fat packages’ in my book), but that is not evidence that plant sterols reduce CVD risk.

First of all, the link between CVD and LDL cholesterol level (as opposed to the distribution of LDL particle sizes) is tenuous. Second of all, in addition to modifying cholesterol, plant sterols seem to also have other harmful effects. If anything, the limited evidence that exists suggests that the net effect of plant sterol supplementation is harmful, not helpful. This is all summarized nicely in a recent review1.

Like plant sterols, niacin has also been shown to lower LDL cholesterol. Unlike plant sterols, there has actually been a large clinical trial testing the effects of niacin supplementation on CVD2. While niacin did indeed lower LDL cholesterol, it had no effect on CVD, and it had serious adverse side effects ranging from diabetes to serious bleeding events. If a similar clinical trial on plant sterol supplementation is ever conducted, it will likely turn out the same way.

While we’re on the topic of supplements, here is a complete list of the vitamin, mineral, and antioxidant supplements that significantly reduce CVD risk3,4:



That is not an error either. It really shouldn’t come as a surprise that supplements tend to either have no impact or a negative impact. CVD risk is determined by the interactions of complex systems with a high degree of redundancy (i.e. many different elements perform the same function), which makes them resistant to small perturbations, as well as a high degree of multitasking (i.e. the same element performs many different functions), which make the effects of large perturbations hard to predict. Using supplements in attempt to manipulate the function of these systems in the absence of evidence from high-quality clinical trials is a waste time at best, and seriously dangerous at worst.

If you really care about staying lean and healthy, forget about supplements and put your time, effort, and money into finding ways to help yourself be more active and eat fewer processed foods.

1. Weingärtner O, Teupser D, Patel SB. The Atherogenicity of Plant Sterols: The Evidence from Genetics to Clinical Trials. J AOAC Int. 2015 May-Jun;98(3):742-9.

2. HPS2-THRIVE Collaborative Group, Landray MJ, Haynes R, Hopewell JC, Parish S, Aung T, Tomson J, Wallendszus K, Craig M, Jiang L, Collins R, Armitage J. Effects of extended-release niacin with laropiprant in high-risk patients. N Engl J Med. 2014 Jul 17;371(3):203-12.

3. Bjelakovic G, Nikolova D, Gluud C. Antioxidant supplements and mortality. Curr Opin Clin Nutr Metab Care. 2014 Jan;17(1):40-4.

4. Moyer VA; U.S. Preventive Services Task Force. Vitamin, mineral, and multivitamin supplements for the primary prevention of cardiovascular disease and cancer: U.S. Preventive services Task Force recommendation statement. Ann Intern Med. 2014 Apr 15;160(8):558-64.