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Protocol for The Big Cholesterol Experiment


The principle aim was to demonstrate that small dietary changes can have a reasonable impact on your blood cholesterol concentrations. Volunteers with high low density lipoprotein (LDL) cholesterol levels were randomised into three treatment groups of low cholesterol, oats, or almonds over a one month period.

Experimental design and methods

The design was a randomised study, with a one month intervention across three different treatment groups. Definitions of raised cholesterol were based on government recommendations that total cholesterol should be 5 mmol/L or below and that LDL should be3 mmol/L or below.

To be eligible, volunteers needed to have elevated low density lipoprotein (LDL) cholesterol levels, but be otherwise healthy.


All volunteers had to attend a screening at the Metabolic Research Unit in Kings College London. This was to determine their blood cholesterol levels, and overall health. As well as their LDL cholesterol, their total cholesterol, high density lipoprotein (HD) cholesterol, and total cholesterol to HDL cholesterol were recorded. As a result, 42 were eligible and they were randomised into three dietary intervention groups. The two groups adding in foods were told to integrate the changes into their normal diets to avoid any weight gain or loss. The low cholesterol group was given specific diet instructions.

Intervention 1

Low cholesterol diet. The groups were given a list of foods to avoid, foods to choose instead, and cooking instructions. The main focus was on cutting down on animal fats and replacing them with vegetable based or low fat options. For example, they were recommended to choose vegetable based spread rather than butter, for beef and pork to have no fat trims, and to avoid bacon, full fat-cheese and sausages.

Intervention 2

75g of dried oatmeal per day, which is equivalent to three servings. This group were told to integrate this change into their normal diet to avoid any weight gain or loss.

Intervention 3

60g of plain roasted almonds per day. This group were similarly told to integrate this change into their day to day diet.

At the end of the 28 day period, the volunteers had their levels taken again at the Metabolic Research Unit. As at the beginning of the study, their LDL, HDL, total cholesterol, and total cholesterol to HDL cholesterol were recorded. Following this, their final results were analysed and compared to those at baseline.