From the Guidelines
Oatmeal reduces cholesterol primarily through its high content of soluble fiber, specifically beta-glucan, which forms a gel-like substance in the digestive tract that binds to cholesterol-rich bile acids, preventing their reabsorption and promoting their excretion from the body, as supported by the most recent evidence from 1. The mechanism of oatmeal in reducing cholesterol involves the soluble fiber beta-glucan, which is fermented by gut bacteria to produce short-chain fatty acids that may inhibit cholesterol synthesis in the liver.
- The cholesterol-lowering effect of oatmeal is most pronounced for LDL ("bad") cholesterol, with reductions typically ranging from 5-10% when oatmeal is part of a heart-healthy diet, as noted in 1.
- Consuming 3-5 grams of beta-glucan daily, equivalent to about 1.5 cups of cooked oatmeal, is recommended for effective cholesterol reduction, with steel-cut or rolled oats providing more beta-glucan than instant varieties, making them more effective choices.
- Regular consumption of oatmeal is key, as the cholesterol-lowering effects are not permanent and require consistent intake, as indicated by the health claims approved in 1. The benefits of oatmeal in reducing cholesterol are well-established, and its inclusion in a heart-healthy diet can have a significant impact on reducing the risk of cardiovascular disease, as supported by the evidence from 1 and 1.
From the Research
Mechanism of Oatmeal in Reducing Cholesterol
The mechanism of oatmeal in reducing cholesterol levels can be attributed to its soluble dietary fiber, specifically oat β-glucan. Key points about this mechanism include:
- Oat β-glucan has been shown to reduce plasma total and low-density lipoprotein (LDL) cholesterol levels by 5-10% in normocholesterolemic or hypercholesterolemic subjects 2.
- The daily intake of at least 3 g of oat β-glucan is necessary to achieve significant reductions in cholesterol levels 2, 3.
- Oat consumption has been associated with 5% and 7% reductions in total and LDL cholesterol levels, respectively 2.
- The soluble fiber in oatmeal, β-glucan, interacts with lipids and biliary salts in the bowel, reducing cholesterol levels 4.
Key Findings
Some key findings from studies on the effect of oatmeal on cholesterol levels include:
- A randomized, crossover design study found that daily oat consumption reduced total cholesterol by 5% and LDL-cholesterol by 10% from baseline levels in hypercholesterolemic Thai adults 3.
- A study on whole-grain ready-to-eat oat cereal found that it lowered LDL cholesterol levels and improved other cardiovascular disease risk markers more than a dietary program alone 5.
- β-glucans, found in oatmeal, may be developed as a suitable therapeutic option to treat patients with dyslipidemia, as they are natural molecules that do not induce significant side effects 4.
Effects on Lipid Profiles
The effects of oatmeal on lipid profiles include: