Does Oatmeal Spike Insulin?

Incorporating oatmeal as part of a nutritious diet plan is vital for overall health and well-being. The American Heart Association explains that oatmeal may help to lower cholesterol levels. Furthermore, the fiber content of oatmeal may also help to promote digestive health. Health experts recommend oatmeal to diabetics as treatment for elevated blood-glucose levels as it regulates the production of insulin. Consult with your healthcare adviser or nutritionist before implementing dietary changes.

Oatmeal with blueberries (Image: Sally Scott/iStock/Getty Images)

Importance of Insulin

The presence of glucose in the bloodstream signals the body to produce a type of hormone known as insulin. Insulin enables the body to either utilize the glucose as energy or to store leftover glucose, in the form of fat, for future use. Too little or too much insulin may induce health complications, such as diabetes or hyperinsulinemia, a condition in which the body exhibits insulin resistance and compensates by producing more insulin. Although the body converts oatmeal and other carbohydrates into glucose, not all carbohydrates are created equal. Healthcare professionals developed a system of measurement, known as the glycemic index, to determine the impact certain carbohydrates have on blood-glucose levels, and therefore, on insulin production.

Glycemic Index

Some carbohydrates elevate blood glucose levels at a quicker pace than other carbohydrates and knowing the glycemic index rating of carbohydrates will help to determine which foods may cause a spike in insulin levels. According to the University of Sydney, foods with a low glycemic index of between 0 and 55 have the least impact on blood-glucose levels while foods with a glycemic index rating above 69 have the most impact on blood-glucose levels. Foods with a glycemic index rating of between in between 56 and 69 have a moderate impact on blood-glucose levels. The average 250 gram serving of oatmeal has a moderate impact on blood-glucose levels as its glycemic index rating is 58.

Impact of Oatmeal on Insulin

Researchers at Pennsylvania State University note that oatmeal helps to stabilize insulin levels much longer than most food products. One explanation is that oatmeal has a high soluble fiber content whereas most vegetables contain insoluble fiber. Soluble fiber digests at a slower rate than insoluble fiber, which in turn helps to slow the production of insulin. A steady production of insulin prevents blood-glucose fluctuations and may also stimulate weight-loss by controlling food cravings.

Considerations

Although most oatmeal varieties, such as steel cut or old-fashioned oats, do not significantly elevate blood-glucose levels, the ingredients found in instant oatmeal may cause insulin levels to spike. Instant oatmeal sometimes contains sugar or sweetened dried fruits that may impact the rate at which insulin is released. The glycemic index rating of instant oatmeal is between 69 and 83, more than 10 glycemic points higher than old-fashioned oats. Incorporating protein, such as soy milk or almond butter, to the oatmeal may help to reduce its glycemic index and regulate insulin levels.