Raisins pouring over oatmeal
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Eating oatmeal regularly may help lower your risks for high cholesterol, stroke, heart disease, obesity, cancer and diabetes. You can choose old-fashioned, quick or instant oatmeal as well as flavored and unflavored individual oatmeal packets. While all offer similar benefits, there are differences in preparation, taste and health benefits.

Preparation

Instant is the fastest and easiest type of oatmeal to prepare, since it doesn't require cooking. You simply add hot water, as this type of oatmeal has been processed to cook fast. However, even quick and old-fashioned oatmeals don't take that long to cook. You can fix quick oatmeal in a microwave in just a minute or on the stove in three or four minutes, while old-fashioned oatmeal takes about two minutes in the microwave and five to 10 minutes on the stove.

Nutrition

All types of plain oatmeal have basically the same nutritional profile, whether old-fashioned, quick or instant. They all contain about 166 calories, 6 grams of protein, 3.5 grams of fat and 4 grams of fiber. However, be careful when choosing instant flavored oatmeal, as some types have quite a bit of added sugar or salt. It is preferable to use plain oatmeal and add your own sweetener and flavoring; that way, you can control how much sugar and sodium you consume.

Glycemic Index

Stove-top oatmeal, including old-fashioned and quick varieties, is a better option than instant oatmeal for people who are watching blood sugar levels. While all types of plain oatmeal contain the same nutritional profile, old-fashioned oatmeal has a much lower glycemic index than instant oatmeal. The glycemic index is a way of measuring how much a carbohydrate-containing food increases your blood sugar levels in the two hours after you consume it.

Taste

The longer-cooking oatmeal has a better flavor and texture than the faster-cooking or instant types, according to a November 2008 article published in "Consumer Reports." If you have the time, steel-cut oats, which take 25 to 30 minutes to cook on the stove and require a four-to-one ratio of water to oats, have even better flavor than all three types of common, rolled oats. Steel-cut oats are whole oats that have been cut into chunks, whereas the other types have been rolled flat to speed up cooking time. If you don't have time to make oatmeal in the morning, prepare it ahead and reheat it in the morning; this will not be detrimental to the nutritional content.